Dissertations / Theses: 'Feline immunodeficiency virus'

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Caney, Sarah Madeline Amanda. "Mucosal immunopathogenesis of feline immunodeficiency virus infection." Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341499.

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Camerini, Valentina. "Translational control of feline immunodeficiency virus (FIV)." Lyon, École normale supérieure (sciences), 2006. http://www.theses.fr/2006ENSL0387.

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Buck, Wayne R. "Neuropathogenic mechanisms of feline immunodeficiency virus infection." Columbus, Ohio : Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1078414064.

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Thesis (Ph. D.)--Ohio State University, 2004.
Title from first page of PDF file. Document formatted into pages; contains xiv, 144 p.; also includes graphics (some col.). Includes abstract and vita. Co-advisors: Lawrence E. Mathes and Maria H. Neff, Dept. of Veterinary Biosciences. Includes bibliographical references (p. 122-144).

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Leal, Rodolfo Assis Oliveira. "Recombinant feline interferon omega therapy in cats naturally infected with Feline Immunodeficiency Virus : clinical, viral and immunological relevance." Doctoral thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/7458.

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Tese de Doutoramento em Ciências Veterinárias Especialidade de Clínica
Type-I Interferons are well-known cytokines which among their main functions are key components of the host immune response against viral infections. Due to its immune modulation properties, they are commonly used in the therapeutic approach of various diseases such as retroviral infections. Recombinant feline interferon omega (rFeIFN-ω) is the first interferon licensed for use in veterinary medicine. Although it is commonly administered in retroviral infections, namely in Feline Immunodeficiency Virus (FIV) and Feline Leukemia Virus (FeLV) infected cats, few studies reported its clinical benefits and mechanisms of action. This thesis aims to clarify the main properties of the licensed rFeIFN-ω protocol (3 cycles of 5 daily subcutaneous administrations of 1MU/kg beginning on days 0, 14 and 60) in naturally retroviral infected cats living in an animal shelter, evaluating its effect not only on clinical improvement but also on concurrent viral excretion, viremia/proviral load and various immune biomarkers such as acute phase proteins and cytokine profile. Recognizing the non specific and subtle clinical presentation of the majority of FIV-infected cats, this work also presents and evaluates an alternative oral rFeIFN-ω protocol (0.1MU/cat during 90 days) to be used in client-owned FIV-infected cats. Results showed that the licensed rFeIFN-ω protocol induces a significant clinical improvement, with a concurrent reduction of opportunistic viral infections and an increase on acute phase proteins (APP) profile. The alternative protocol also revealed an important clinical improvement but without significant changes on opportunistic viral infections (which were of low level in the tested group) or on APP profile. In both protocols, no changes were remarked on viremia neither on T-helper 1/T-helper 2 cytokine profiles meaning that this compound may lack an anti-viral activity for retroviruses in vivo and do not act on the acquired immune response of FIV-positive cats. However, there was a significant reduction of the interleukin-6 plasma levels (pro-inflammatory cytokine) in cats treated with the licensed protocol and a decrease on its mRNA expression in cats treated orally. This shows that rFeIFN-ω can have anti-inflammatory properties, which are more evident in the higher doses of the licensed protocol. More than contributing for a better knowledge of rFeIFN-ω, this thesis explores its immune modulation properties and validates a new oral protocol which can be included on future FIV-guidelines.
Resumo - A terapêutica com interferão ómega felino em gatos naturalmente infectados com o vírus da imunodeficiência felina: relevância clinica, virológica e imunitária - Os interferões do tipo I são citoquinas chave do sistema imunitário. Devido às suas propriedades imunomoduladoras, são um recurso terapêutico frequente em diferentes doenças como as infecções retrovirais. O interferão ómega felino (rFeIFN-ω) é o primeiro interferão licenciado para medicina veterinária. Apesar do seu uso no tratamento de infeções retrovirais como o vírus da imunodeficiência felina (FIV) e o vírus da leucemia felina (FeLV), são poucos os estudos que fundamentam o seu benefício clinico. Esta tese visa clarificar as propriedades terapêuticas e imunomoduladoras do protocolo licenciado de rFeIFN-ω (3 ciclos de 5 administrações subcutâneas de 1MU/kg uma vez ao dia a iniciar aos dias 0, 14 e 60) em gatos naturalmente infectados por retrovírus e residentes em gatil. Em detalhe, este trabalho avalia o efeito deste fármaco na melhoria clinica, na excreção de vírus concomitantes, na virémia/provirus e na variação de diferentes marcadores imunitários como proteínas de fase aguda e perfil de citoquinas. Esta tese contempla ainda o desenvolvimento de um protocolo terapêutico alternativo baseado na administração oral de rFeIFN-ω (0.1MU/gato durante 90 dias consecutivos) para uso em gatos FIV-positivos domésticos, os quais apresentam geralmente um quadro clinico subtil e pouco específico. Os resultados revelaram que o protocolo licenciado induz uma melhoria clinica significativa com redução concomitante das infecções oportunistas e um aumento do perfil de proteínas de fase aguda (APP). O protocolo alternativo revelou-se eficaz na melhoria clinica dos animais tratados, apesar de não induzir alterações significativas do perfil de APPs nem das infecções concomitantes (residuais no grupo de estudo). Ambos os protocolos não induziram alterações na virémia nem no perfil de citoquinas participantes nas respostas T-helper 1 ou T-helper 2 o que sugere que este composto não apresenta propriedades anti-virais nem actua na imunidade adquirida de gatos FIV positivos. Verificou-se contudo um decréscimo dos niveis plasmáticos de Interleucina-6 (citoquina pro-inflamatória) em gatos tratados com o protocolo subcutâneo e uma redução da sua expressão (mRNA) em gatos tratados por vira oral. Tal demonstra que o rFeIFN-ω apresenta propriedades anti-inflamatórias, as quais são mais evidentes aquando do tratamento com o protocolo licenciado. Mais que uma contribuição para um melhor conhecimento do rFeIFN-ω, esta tese explora as suas propriedades imunomoduladoras e valida um novo protocolo oral, o qual poderá ser incluído em futuras guidelines para o tratamento de gatos FIV-positivos.
Trabalho financiado também pelo Centro de Investigação Interdisciplinar em Sanidade Animal (CIISA) da Faculdade de Medicina Veterinária, Universidade de Lisboa e Virbac (Centro de Custos phD_Virbac).

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Haining, Hayley. "Studies of the pathogenesis of feline immunodeficiency virus." Thesis, University of Glasgow, 2004. http://theses.gla.ac.uk/5512/.

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The project had three aims: namely: - (i) to investigate the in vitro cell tropism of a range of field isolates from cats at different stages of disease and compare their phenotype with the well-characterised prototype viruses FIV-PET and FIV-GL8. (ii) to study the pathogenicity of these viruses in vivo in order to examine any correlation between virulence in vivo and tropism in vitro. (iii) to look at the role of the env gene in the pathogenicity of FIV. In vitro studies of cell tropism revealed that isolates from cats in the terminal stage of disease had a greater ability to utilise CXCR4 than isolates from cats displaying no clinical signs. In vivo, these symptomatic isolates, with greater CXCR4-tropism in vitro, displayed less virulence when compared with isolates from asymptomatic cats. Chimaeras were made by inserting the env genes of an isolate from the asymptomatic or terminal disease stages into a FIV-G8Mya backbone, allowing comparison of the cell tropism and receptor usage of these genes and the study of their phenotype with regard to virulence in vivo. The env genes from FIV-PET and the symptomatic isolate (F0827Hs) had a greater affinity to utilise CXCR4 for cell entry in vitro and this correlated with reduced virulence in vivo when compared to the asymptomatic isolate env and FIV-G8Mya. These studies highlight a trend where tropism in vitro can be correlated with virulence in vivo. Furthermore, the study indicated that viruses from asymptomatic cats (with a lesser ability to utilise CXCR4) have increased virulence. As these are the agents most likely to be transmitted in the field by the apparently healthy cat, vaccine development should focus on this population of viruses.

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Gemeniano, Maria Lourdes Charmaine. "Characterization of Orf-A of feline immunodeficiency virus /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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Bęczkowski, Paweł. "Virus evolution in the progression of natural feline immunodeficiency virus infection." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4186/.

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Feline immunodeficiency virus (FIV) is an important pathogen of domestic cats which in some cases can lead to feline AIDS. It shares many similarities with its human counterpart and is studied to understand correlates of immune-protection and mechanisms of disease progression in cats, both to improve the welfare of infected cats and as an animal model for the pathogenesis of HIV infection in humans. FIV is believed to evolve during the course of infection as a result of the error prone nature of reverse transcriptase and recombination between viral variants, but relatively little is known about this process in naturally occurring infection. Ultimately, it remains unknown why some infected cats remain healthy while others progress to AIDS rapidly. The studies reported in this thesis addressed this lack of knowledge by examining sequential blood samples obtained during the course of natural FIV infection in a population of 44 privately owned domestic cats. Employing Bayesian coalescent framework, it was demonstrated that the FIV env gene is relatively stable genetically. Although not necessary a prerequisite, this is likely to explain why many naturally infected cats can remain healthy and do not progress to AIDS. By determining the cell tropism of isolated viral variants, it was shown that sick cats were more likely to harbour viruses of the “late” phenotype than healthy animals, similar to the co-receptor switch observed during the progression of HIV infection. Intra-host diversity analyses highlighted a likely role for the leader region of the env gene in viral pathogenesis. Furthermore, recombination was demonstrated to be abundant in natural infection, indicating a requirement for the current phylogenetic classification of FIV to be revised. By assessing the strength and breadth of neutralising antibodies (NAbs), it was shown that NAbs did not appear to influence the course of natural FIV infection, arguing against a role in controlling infection and disease progression. Following an examination of samples collected from a group of privately owned Australian vaccinates, it was shown that the Fel-O-Vax FIV vaccine did not induce cross-reactive neutralising antibodies. Furthermore, in the country where commercial FIV vaccine is licenced, we identified and characterised the virus strain which was likely able to establish infection in vaccinated cat and raised concerns of vaccine’s efficacy. Overall this study broadens our understanding of natural FIV infection, and highlights that much can be learned, not from the similarities but rather by studying the differences between the feline and human lentiviruses. Such comparative studies are likely to contribute to design of highly desirable, safe and fully efficacious lentiviral vaccines.

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Chan, Chi Ngai. "Cell signalling and feline immunodeficiency virus growth and latency." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/3889/.

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The replication of CD4+ T cell-tropic retroviruses such as the human immunodeficiency virus-1 (HIV-1) and the feline immunodeficiency virus (FIV) is intricately linked to host cell signalling and activation status. This intimate relationship between the viruses and their respective hosts plays crucial roles in the pathogenesis of each virus. Focusing on FIV, this thesis examined several questions relating to virus replication and cell signalling. Firstly, the possible cell stimulatory effect when FIV Env binds to its primary receptor CD134 was investigated and results suggested that FIV does not trigger CD134 signalling. Next the activation status of susceptible CD4+ T cells was manipulated to study FIV latency and it was shown that by removing exogenous supplement of the cytokine interleukin-2 (IL-2) from MYA-1 feline CD4+ T cells 24 hours before infection, productive FIV replication is down-regulated such that only a very low level of ongoing virus replication can be detected among the IL-2-depleted cells with a sensitive qPCR assay. The phorbol esters PMA and Prostratin can stimulate high level of productive infection from these IL-2-depleted MYA-1 cells and this is mediated by a protein kinase C (PKC) dependent mechanism. Furthermore, productive replication of FIV in the presence of IL-2 is blocked by stimulation of PKC with phorbol esters, which is analogous to findings of similar experiments with HIV-1. However, inhibition of viral replication is not at the level of viral entry, contrary to the findings of HIV-1 studies. The mechanism behind the Prostratin-mediated inhibition of FIV remains elusive. It was also discovered that ‘early’ and ‘late’ strains of FIV responded differently to cell signalling manipulation and an attempt was made to map the viral genome region(s) responsible. Preliminary data showed that both env and the 5’UTR may mediate the inter-strain differences in replication dynamics. Overall this thesis shows the complete dependency of FIV on host cell signalling, in particular optimum PKC activation to achieve productive viral replication. This may reflect the tropism of the virus. The similarities between HIV-1 and FIV replication and latency support the notion of using FIV and the cat as a model for HIV-1 latency in the development of novel therapeutic measures to eradicate hidden HIV-1 from the host. However, more research is required to fully characterise the differences between HIV-1 and FIV biology.

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Grant, Susan Elizabeth. "Studies on haemopoiesis in early feline immunodeficiency virus infection." Thesis, University of Glasgow, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296042.

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Samman, Ayman. "The role of virus neutralisation in immunity to feline immunodeficiency virus infection." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1554/.

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Feline immunodeficiency virus (FIV) is an important veterinary pathogen with comparative significance because of its similarities to its human counterpart HIV. Since FIV is the only non-primate lentivirus which induces AIDS-like symptoms in its natural host, it serves as a valuable animal model for both prophylactic and therapeutic studies of HIV. It is accepted that the induction of neutralising antibodies (NAbs) is a key element in the control of lentiviral infection, since T-cell based vaccines alone failed to prevent infection in most experimental animal model systems. In this project a robust and reproducible in vitro neutralisation assay was developed and optimised, permitting the assessment of the NAb response in naturally infected cats and with the potential to evaluate candidate vaccines. It was demonstrated that, in general, primary FIV strains in the UK belong to subtype A, and therefore the development of a regional, subtype A-specific, FIV vaccine could be considered for use in the UK. The identification of a neutralisation resistant isolate of FIV led to the finding that a linear neutralisation determinant was located within the V5 region of Env and mutations in this region may lead to immune evasion in vivo. In addition, a second neutralisation determinant was identified in the C3/V4 region of Env. Finally, it was observed that a small proportion of naturally infected cats generated NAbs against FIV. Of these, only a very small proportion of the cats had antibodies with the potential to cross neutralise strains within the same subtype as the homologous isolate. Nonetheless, a plasma sample from a single cat was identified that neutralised all strains tested, including strains from different subtypes and geographical regions. It is likely that studies of the homologous isolate that induced the broad NAb response may be capable of inducing a similar broad response in vaccinated cats. Such a finding would have important implications for the design of potential novel lentiviral immunogens.

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Frey, Susan Carol Stankewitz. "The role of CXCR4 in feline immunodeficiency virus cell entry /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/11487.

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Meers, Joanne. "The effects of antiviral agents on feline immunodeficiency virus infection." Thesis, Meers, Joanne (1994) The effects of antiviral agents on feline immunodeficiency virus infection. PhD thesis, Murdoch University, 1994. https://researchrepository.murdoch.edu.au/id/eprint/53284/.

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Feline immunodeficiency virus (FIV) is a recently discovered lentivirus with many structural and replicative similarities to human immunodeficiency virus (HIV), and has been suggested as a useful animal model for the evaluation of anti-HIV chemotherapy. The successful use of the model is dependent on the development of techniques to accurately measure the response to antiviral treatment in FIV-infected cats. FIV was isolated by the co-cultivation of peripheral blood mononuclear cells (PBMC) from seropositive cats with PBMC of seronegative donor cats, or with MYA-1 cells (a feline T-lymphoblastoid cell line). Propagation of FIV isolates was unsuccessful in Crandell feline kidney cells, but was successful in PBMC cultures, primary feline thymocytes, and MYA-1 cells. The biological characteristics of 3 West Australian isolates of FIV were compared. The isolates had similar properties to each other, and to other reported isolates of FIV, including similar cytopathic effect (CPE), electron microscopic appearance, magnesium-dependent reverse transcriptase (RT) activity, FIV p26 core antigen production and the nucleotide sequence of gag and pol genes. Tetrazolium-based colourimetric assays were used to quantify the CPE of FIV by demonstrating the loss of cell viability in FIV-infected MYA-1 cell cultures. These assays were then used for the titration of FIV, to assess the cytotoxicity of antiviral agents in vitro, and to determine the protection provided by antiviral agents against the CPE of FIV. Five of 6 agents evaluated by these assays provided protection against CPE induced by 2 isolates of FIV. These agents consisted of 4 RT inhibitors (zidovudine, ddC, ddI, foscarnet) and one inhibitor of virus binding/entry (dextran sulphate). A novel agent, acemannan, provided no protection against the CPE of FIV. The inhibition by zidovudine of RT activity and FIV p26 antigen levels in culture supernatant was also demonstrated. The titre of FIV in PBMC and plasma was determined in 18 experimentally-infected cats and 2 naturally-infected cats, by end-point dilution cultures. The proportion of PBMC containing provirus was determined by polymerase chain reaction (PCR) on serially diluted samples of PBMC from 10 cats. It was demonstrated that following inoculation with virus, the titre of FIV in PBMC increased rapidly to a relatively high level which was then maintained for up to 8 months. In most cats, approximately 1 in 200 PBMC contained virus by 4 weeks post inoculation (p.i.). The results from PCR generally correlated with those from virus isolation, suggesting that the proportion of FIV provirus that is replication defective may be comparatively low. The titre of FIV in plasma peaked at approximately 2 weeks p.i., and then in many cats, declined to undetectable levels. Virus was not isolated from plasma of 2 naturally-infected cats. In some cats, plasma virus titres did not decline by up to 32 weeks p.i., suggesting that there is a variation in the immune response, which enables some, but not all, cats to clear virus from plasma. The effect of treatment with cyclosporine on the virus titre in cats experimentally infected with FIV was investigated. Treatment began 24 hrs p.i., and continued for 4 weeks. Cyclosporine treatment lowered plasma virus titres at 2 weeks p.i., but at 4 weeks p.i. the plasma virus titre of cyclosporine-treated cats was significantly higher than in untreated cats. This suggested that, initially, the suppression of T-cell activation resulted in the inhibition of viral expression and lower plasma virus titres. However, the broader immunosuppressive effect of treatment eventually dominated the former effect, resulting in an inability to control viral replication and/or clear virus from plasma. Cyclosporine treatment did not influence the titre of FIV in PBMC. The studies on virus load, combined with the cyclosporine data, suggest that the immune response plays a major role in the control of plasma virus titres in lentiviral infections, but has little influence on the level of cell virus titres. Treatment of infected cats with zidovudine resulted in significant effects on virus load. Two different dose rates of zidovudine, administered at different times p.i. and with different durations of treatment, were assessed. Zidovudine treatment, with either dose regime, did not prevent establishment of infection with FIV. However, the plasma virus titre of zidovudine- treated cats, using either dose regime, was significantly lower than in untreated cats on at least one sampling occasion. The PBMC virus titre of cats treated with the higher dose of zidovudine was significantly lower than untreated cats at two sampling times. Treatment with the lower dose of zidovudine did not significantly influence PBMC virus titre. This suggested that while the effect of zidovudine on the level of PBMC virus titre may predominantly be the result of the inhibition of viral RT, the effect of zidovudine on plasma virus titres may be the result not only of RT inhibition, but also the result of the suppression of T-cell activation by zidovudine. This work established methods by which the effect of antiviral or immunomodulating agents on the titres of FIV in PBMC and plasma of infected cats can be investigated and has demonstrated that FIV infection can be used as an effective animal model for the evaluation of antiviral agents against HIV. It has also contributed to the broader investigation of the immunopathogenesis of lentiviral infections.

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Hopper, Cherida Dawm. "Studies on the epizootiology of feline immunodeficiency virus infection in cats." Thesis, University of Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335478.

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Garg, Himanshu. "Feline Immunodeficiency Virus (FIV) Envelope Glycoprotein-Mediated Cell Fusion and Apoptosis." NCSU, 2003. http://www.lib.ncsu.edu/theses/available/etd-11042003-141554/.

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Feline Immunodeficiency Virus (FIV) and Human Immunodeficiency Virus (HIV) are lentiviruses that are remarkable similar in their genomic organization, receptor usage and pathogenesis. Based on this FIV has evolved into a well-established small animal model for studying AIDS. FIV and HIV cause a progressive depletion of T cells via a still unknown mechanism though numerous studies support a role of membrane expressed HIV env glycoprotein in apoptotic killing of CD4+ T cells. HIV env glycoprotein is a heterodimer of surface expressed gp120 that binds to CD4 and a chemokine receptor and transmembrane gp41 that mediates fusion and syncytia formation. The role of the fusion process in HIV env-mediated apoptosis remains controversial even though evidence suggests that cytopathic effect of HIV is related to the fusogenic potential of env glycoprotein. Blocking HIV env receptor interactions either at the level of gp120 or gp41 blocks both syncytia formation and apoptosis. This suggests a crucial role for HIV gp41 in fusion, as well as apoptosis. The hydrophobic pre-transmembrane (pre-TM) region of HIV gp41 is important for membrane fusion and sequence analysis reveals a similar region in FIV gp41. The current study was undertaken to determine the role of different regions of FIV env in mediating fusion and apoptosis in bystander cells and to determine whether the two phenomena are related. FIV env interactions with target cells were blocked at the level of gp120 or gp41 and the effect of these on fusion and apoptosis studied. The role of FIV gp41 pre-TM region in fusion and apoptosis was also determined. Our findings support a role of FIV env in apoptotic loss of T cells and this phenomenon correlates with env-mediated fusion.

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McEwan, William. "Factors affecting replication and cross-species transmission of feline immunodeficiency virus." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1388/.

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In order to successfully invade a new species, lentiviruses must overcome restriction factors, dominant blocks to replication, and be able to make use of available host factors such as entry receptors for replication. Human immunodeficiency virus (HIV-1) infection is blocked at a post-entry stage by rhesus macaque TRIM5α, an effect that is enhanced by host factor cyclophilin A (CypA), but largely evades restriction by the human TRIM5α variant. HIV-1 replication is also inhibited by simian APOBEC3G but is able to evade restriction by human APOBEC3G by inducing its degradation through expression of accessory protein Vif. Viral entry and tissue tropism are determined by an interaction of the viral Env glycoprotein with a cell surface receptor and a seven transmembrane domain co-receptor. The feline immunodeficiency virus (FIV) infects diverse felid species including the African lion, where infection has likely been endemic since at least the late Pleistocene, and the domestic cat, a more recent host. For domestic cat strains of FIV (FIV-Fca), entry is mediated by host proteins CD134 and CXCR4, but the identity of receptors in non-domestic strains of FIV is unknown. This thesis demonstrates that two strains of FIV isolated from lions (FIV-Ple subtypes B and E) differ in their receptor tropism and that subtype E shares entry receptors with FIV-Fca. The findings suggest that alternative receptor usage is a strategy employed by FIV in this species and has implications for the disputed pathology and tissue tropism of infection in African lions. Next, we tested the hypothesis that species which have harboured lentiviral infection for a long time are better able to prevent viral replication than recent hosts. Whilst we found that TRIM5α is non-functional in all felid species tested, evidence of potent APOBEC3 activity was found and, in lion cells, potently restricts production of infectious FIV. Moreover, lion primary T-cells prevent replication of diverse FIV strains and restrict primate lentiviruses at post-entry stages, suggesting that co-evolution with lentiviruses has driven the selection of broad-ranging restriction factors. Structural and biophysical analyses suggest that whilst FIV’s interaction with CypA appears to be conserved in affinity with HIV-1, the interaction does not appear to be crucial for replication and, in the absence of restriction by TRIM5α, the role of the capsid-CypA interaction is discussed. Overall the study explains the permissivity of domestic cat cells to retroviral infection and identifies FIV infection of lions as an example of host adaptation driven by current lentiviral infection.

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Cheng, Heather H. "Envelope and receptor determinants for infection by an immunodeficiency-associated feline leukemia virus /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/5010.

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Gu, Qinyong [Verfasser]. "The molecular interaction of feline immunodeficiency virus Vif with feline APOBEC3 and Cullin 5 / Qinyong Gu." Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1162840072/34.

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Kraase, Martin [Verfasser]. "The virus-receptor interaction in the pathogenesis of feline immunodeficiency virus infection / Martin Kraase." Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1049687663/34.

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Leal, Magda Liliana Garcia. "Avaliação da freqüência da infecção por micoplasmas hemotrópicos em gatos com linfoma." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-17042009-141814/.

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Com o objetivo de avaliar a freqüência de infecção por micoplasmas hemotrópicos em gatos com linfoma e seu impacto na ocorrência de anemias nesses animais, foram analisadas amostras sangüíneas de 14 animais com diagnóstico de linfoma, sem qualquer tratamento prévio e 14 amostras de sangue de gatos hígidos, por meio da técnica de PCR-Nested. Utilizaram-se primers que amplificam fragmentos do gene 16S rRNA dos micoplasmas. Eritrograma e bioquímica sérica foram realizados, assim como testes sorológicos imunoenzimáticos (ELISA) para ambos os retrovírus. Anemia foi observada em 28,6% (4/14) dos gatos com linfoma. Em dois a anemia foi classificada como normocítica normocrômica não regenerativa, e em outros dois como macrocitica normocrômica não regenerativa. A freqüência de infecção pelos micoplasmas hemotrópicos felinos nos gatos com linfoma foi de 7,14% (1/14). Após seqüenciamento e posterior prova de identidade no GenBank, o agente foi identificado como M. haemofelis, número de acesso FJ544859. A freqüência de infecção pelos retrovírus foi de 21,42% para o FeLV e 7,14% (3/14) para o FIV. O animal infectado pelo M. haemofelis não apresentou anemia, ainda que apresentasse infecção concomitante pelo FeLV. O grupo controle não apresentou infecção por micoplasmas ou retrovírus. Nas condições em que este estudo foi realizado, concluiu-se que a anemia observada nos gatos com linfoma não foi ocasionada pela infecção por micoplasmas hemotrópicos, mas provavelmente em decorrência das alterações hematológicas promovidas pelo processo neoplásico, associadas ou não à infecção pelo FeLV. Portanto, a infecção pelos micoplasmas não apresentou um impacto direto na ocorrência de anemias em gatos com linfoma.
To evaluate the frequency of infection by hemotropic mycoplasmas in cats with lymphoma and its impact in the development of anaemia in those animals, blood samples from 14 animals diagnosed with Lymphoma and without any previous treatment and 14 blood samples from healthy cats were analyzed by means of the PCR-Nested technique. Primers were utilized and selectively amplified fragments of 16SrRNA gene of mycoplasma. Haematology, serum biochemical profile and FeLV/FIV ELISA were performed in all 28 cats. Anaemia was observed in 28.6% (4/14) of the cats with lymphoma. In two of them, anaemia was classified as normocytic-normochromic nonregenerative and in the other two as macrocytic-normochromic nonregenerative. The frequency of feline haemotropic mycoplasmas infection in cats with lymphoma was 7.14% (1/14). After sequencing and identity proof by the GenBank, the agent was identified as M. haemofelis, access number FJ544859. The frequency of retrovirus infection among all the cats with lymphoma was 21.42% (3/14) for FeLV and 7.14% (1/14) for FIV. The cat infected by M. haemofelis was also infected with FeLV, but was not anaemic. The 14 cats used as control did not exhibited infection by mycoplasmas or retrovirus infections. Under the conditions in which this study was developed, one can conclude that the anaemia observed in cats with lymphoma may not be related to hemotropic microplasmas infection, but to haematologyc alterations promoted by the associated neoplasic process and/or the occurrence or of FeLV infection. Therefore, the infection by the mycoplasmas did not present a direct impact in the occurrence of anaemies in cats with limphoma.

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Shen, Xiaoying. "Infection of newborn kittens with a feline immunodeficiency virus vif-deletion mutant /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2004. http://uclibs.org/PID/11984.

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Rogers, Melinda Cadd. "Differential thrombospondin expression on T lymphocytes in a Feline Immunodeficiency Virus model." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-06152007-103921/.

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CD4+CD25+ T regulatory cells represent an important subset of lymphocytes whose function is to suppress autoimmune disease and control normal immune responses. There is much research indicating a direct role for TGF-beta expressed on the surface of Tregs in the suppressor function of these cells. TGF-beta, whether bound to the cell surface or secreted, is produced as part of a complex that renders the cytokine inactive. Thrombospondin is the primary activator of biologically latent TGF-beta. This research demonstrates that thrombospondin is expressed on the surface of T lymphocytes isolated from the blood and lymph nodes of normal and FIV positive felines. Thrombospondin is expressed at significantly higher levels on CD4+CD25+ T lymphocytes, but can be induced in culture by activating T helper cells in the presence of LPS and IL2. We also observed that the CD4+CD25- T helper cells isolated from FIV negative control lymph nodes were able to markedly upregulate surface thrombospondin expression compared with similarly stimulated CD4+CD25- T helper cells from FIV positive sources. These findings are initial steps in working to understand the mechanism behind latent TGF-beta activation on CD4+CD25+ T regulatory cells and the role this cell type plays in FIV/HIV pathogenesis.

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22

del, Fierro Gloria M. "Clinical, immunological and pathological aspects of experimental feline immunodeficiency virus (FIV) infection." Thesis, del Fierro, Gloria M. (1995) Clinical, immunological and pathological aspects of experimental feline immunodeficiency virus (FIV) infection. PhD thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/53477/.

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Feline immunodeficiency virus is a recently discovered feline lentivirus which clinically resembles human HIV-1 virus inducing immune dysfunction and secondary infections in cats. FIV presence has been confirmed throughout the world in domestic, feral and zoo cat populations. Older, free-roaming, diseased male cats are at the greatest risk of acquiring the infection. There are no specific clinical signs restricted to FIV infection. However, weight loss, recurrent fever of undetermined origin, unthriftiness, inappetence, pyrexia, lymphadenopathy, anaemia, leucopenia and myeloproliferative disease have been often associated with this infection. Localised chronic progressive infections of the mouth, oral cavity, respiratory tract, skin and external ear canals, gastrointestinal tract, neurologic and renal dysfunction as well as ocular disease have also been reported. Data in this thesis confirms that cats experimentally infected with FIV and observed for up to 77 weeks postinfection display a greater tendency for more severe infection than non-FIVinfected cats. Among the FIV-infected cats, 73% had clinical disease and 27% were asymtomatic. Fever was a feature exclusively seen in 36% of FIVinfected cats in this study. In the same cats hematologic abnormalities include relative lymphopenia, neutropenia and leucopenia in the acute stage of infection. Transient anaemias among FIV-infected cats during the acute phase of infection was also found. No hematologic abnormalities beyond the stage of early infection equivalent to the terminal stage of naturally acquired infection were found. Mortality among FIV-infected cats was 16%, and was limited to the primary stage of infection. There was no mortality in uninfected control cats. Whilst a final or definitive diagnosis is arrived at by virus isolation, the demonstration of FIV antibodies generally establishes a conclusive diagnosis. Throughout this study, serodiagnostic methods such as ELISA, western blot and whole blood agglutination (VetRed™FIV) methods were used. Early detection was accomplished with both ELISA and VetRed™FIV. In experimentally infected cats the sensitivities and specificities of these two methods were comparable. The western blot was not as sensitive in the early phase of infection. A comprehensive field evaluation of the newly available VetRed™FIV commercial test was undertaken which demonstrated that while it was sensitive as the ELISA test, it was not as specific. This study also confirmed the high prevalence of FIV in Western Australian cats, especially mature male cats. At the time of necropsy, FIV was successfully isolated from the bone marrow of all infected cats, but was less frequently isolated from other lymphoid organs such as the lymph node and spleen. In addition, FIV was isolated with high frequency from the salivary gland and kidney. Since the discovery of FIV until the present time, studies on the pathogenesis of FIV have been fragmentary. One aspect of pathogenesis, the effect of FIV on lymphoid tissue was studied in depth. Lymphadenopathy was a consistent finding, which unless lymph node weights are quantified, may be overlooked clinically and at necropsy. In this study lymph node weights of FIV infected cats were twice that of uninfected controls. A regional pattern of enlargement was also apparent, where nodes not exposed to non-specific antigens from mucosal surfaces, like popliteal lymph nodes, were unequivocally enlarged because of hyperplasia. Additionally, the lymphadenopathy was present up to 77 weeks post-infection. Histopathologic evidence of a range of mild, moderate to severe lesions in lymphoid and non-lymphoid organs was seen in this study covering a period from 12 to 77 weeks post-infection. Gross and histopathologic lesions were divided into (1) those exclusive to FIV-infected cats, (2) those seen in both infected and uninfected cats but of a greater severity in FIV-infected cats and (3) those with equal intensity in FIV-infected and uninfected cats. The principal histopathologic alterations observed in lymphoid tissues of FIV-infected cats not previously reported at the time of this study was thymic involution, while B-cell hyperplasia of the popliteal lymph nodes and spleen occurred 2-3 times more commonly in FIV-infected cats than in controls. In non-lymphoid organs, changes were myeloid hyperplasia in the bone marrow, mild to moderate inflammation in the choroid plexus and liver, severe interstitial pneumonia, severe granulomatous ileitis and FlP-associated granulomatous inflammation in multiple organs in some cats. While the most severe lesions occurred in one cat which died acutely at 12 weeks post-inoculation, lesions in cats infected from 21-77 weeks were generally mild to moderate in nature. It is apparent from this experiment that the severity of lesions is not directly influenced by the duration of infection. In conclusion, the outstanding features of experimentally-induced FIV-infection in non-SPF cats were mild leucopenia which encompassed a lymphopenia and neutropenia, limited to the first few weeks of infection. This was accompanied by anemia. More importantly, this study established clinical signs that were exclusive to infection and some signs that occurred with more frequency and were more severe in FIV-infected cats. Significant pathological features included lymphadenopathy, which was present in all FIV-infected cats and persisted up to 77 weeks p.i. The need for quantification to establish the presence of lymphadenopathy is emphasized. In general terms FIV infection induced a widespread B-cell hyperplasia which was not limited to lymph nodes. Accompanying this B-cell hyperplasia and not previously reported was thymic involution. Finally, with respect to the presence of FIV in particular tissues, it is apparent from this work that the preferred site for viral isolation is bone marrow, wherein virus was isolated from every infected cat in these experiments. In contrast, the frequency of isolation from lymphoid tissues such as spleen and lymph node was much less frequent. The reasons for this decreased frequency of isolation were not explored in depth. However, it does suggest that there is either less virus present in these tissues or that the rescue of virus from these tissues is more difficult. A surprising feature of the virus isolation study was the high frequency of recovery of FIV from epithelial tissues such as salivary gland and kidney. This suggests that FIV resides in cells of the bone marrow and lymphoid tissues but also in epithelial cells. The clinicopathologic, pathologic and virologic data from the experiments described herein indicate that FIV produces a mild acute disease and remains clinically silent for a comparatively long period of time. An in depth examination of the differences between the controls and the experimentally infected cats was required in this comparatively subtle infection to detect differences between them.

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Gonsales, Fernanda Fidelis. "Ocorrência de Chlamydophila felis e do plasmídeo críptico em gatis nas cidades de São Paulo e Osasco." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-09092014-153345/.

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A infecção de trato respiratório superior em gatos é uma afecção muito frequente em indivíduos que vivem em abrigos, com elevada morbidade e em alguns casos, fatal. O herpesvírus felino tipo1 (FHV-1) e a Chlamydophila felis estão entre os principais causadores. O FHV-1 ocasiona quadros de espirros, secreção nasal e alterações oculares como conjuntivite. A C. felis é responsável pelos piores casos de conjuntivite e apresenta um plasmídeo críptico como possível fator de virulência. A presença dos retrovírus da leucemia felina (FeLV) e/ou imunodeficiência dos felinos (FIV) debilita a função do sistema imunológico, causando imunossupressão e consequentemente aumento no índice de morbidade e mortalidade. Neste trabalho foram avaliados quatro abrigos, três gatis particulares não-comercias (um localizado em Osasco/SP e outros dois São Paulo/SP). Os gatis possuiam alta densidade populacional e a procedência dos gatos alojados era desconhecida. A detecção de FHV-1, como de C. felis e de três genes do plasmídeo criptico foram realizadas por PCR em amostras de mucosa oral e de conjuntiva ocular de ambos os olhos obtidas com swabs de algodão, secos e estéreis. Amostras de sangue foram coletadas para a detecção do FIV e FeLV por meio de teste imunoenzimático. O sintomas clínicos dos animais foram classificados de 1 a 4, sendo 4 atribuído àqueles que apresentavam pior sintomatologia. A ocorrência de FIV e FeLV no 1° gatil foi de 4,63% e 3,70%, no 2° gatil foi de 0% e 6,45%, enquanto que no 3° gatil foi 75% e 0% respectivamente, estes vírus não foram detectados no 4° gatil. FHV-1 foi observado em 61,11% dos gatos no 1° gatil; 90,32% no 2° gatil, 100% no 3° gatil e em 89,74% dos animais do 4° gatil. No 1° gatil, 7,41% das amostras apresentavam C. felis, no 2° gatil, 58,06%; no 4° gatil, 23,08%; enquanto que no 3° gatil o agente não foi detectado. Dentre as amostras positivas para C. felis, os genes do plasmídeo críptico foram detectados; no 1o gatil o gene 1 estava presente em 62,50% das amostras, o gene 2 e 3 em 75%, para o 2° gatil obteve-se 61,11% de positividade para os genes 1 e 2 e 55,56% para o gene 3; no 4° gatil o gene 1 e 3 estavam presentes em 77,78% das amostras, o gene 2 em 55,56%. Os óbitos relatados no período do estudo foram de animais classificados com sintomas 3 ou 4 e positivos para C. felis e para o plasmídeo críptico. No presente trabalho foi observada uma elevada ocorrência de C. felis e de seu plasmídeo críptico, apesar da baixa ocorrência de FIV e FeLV nos gatis.
The infection of upper respiratory disease in cats is very common in individuals that living in shelters, with high morbidity, and in some cases, fatal. The feline herpesvirus type 1 (FHV- 1) and Chlamydophila felis are agents the main causes. The FHV- 1 causes sneezing, nasal discharge and ocular abnormalities such as conjunctivitis. The C. felis is responsible for the worst cases of conjunctivitis and features a cryptic plasmid as a possible virulence factor. The presence of the feline leukemia virus (FeLV) and/or vírus of feline immunodeficiency (FIV) weaken the function of the immune system, causing immunosuppression and therefore increased morbidity and mortality. This study evaluated four shelters, three catteries private non-commercial (one located in Osasco/SP and two in São Paulo/SP). Catteries possessed high population density and cats housed origin was unknown. The detection of FHV- 1 as three genes of the C. felis and cryptic plasmid was performed by PCR in oral mucosa and the ocular conjunctiva of both eyes obtained with cotton swabs, dried and sterile. Blood samples were collected for the detection of FeLV and FIV by enzyme immunoassay. The clinical symptoms of animals were classified from 1 to 4 , with 4 assigned to worst symptoms. The presence of the FIV and FeLV was in the first cattery 4.63% and 3.70%, in the second cattery was 0% and 6.45%, while in the third cattery was 75% and 0%, respectively, these viruses do not were detected in the 4th cattery. FHV- 1 was observed in 61.11 % of the cats in the first cattery; 90.32 % in the second cattery 100 % in the third and 89.74% of the animals of the fourth cattery. In the first cattery, 7.41% of the samples had C. felis, the second cattery, 58.06 %, in the fourth cattery, 23.08%, while the third cattery the agent was not detected. Among the samples positive for C. felis genes were detected cryptic plasmid; in the first cattery, the first gene was present in 62.50%, gene 2 and 3 in 75% of the samples; for the second cattery was obtained 61.11 % positive for 1 and 2 genes and 55.56 % to the third gene; in fourth cattery the first and the third genes were present at 77.78% of the samples in the second gene was in 55.56%. The deaths reported during the study period were classified in animals with symptoms 3 or 4 and positive for C. felis and the cryptic plasmid. In this study we observed a high incidence of C. felis and the cryptic plasmid, despite the low occurrence of FIV and FeLV in catteries.

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24

Tran, Khanh Van Nhu. "The Effect Of Methamphetamine On Astrocytes With Implications For Feline Immunodeficiency Virus And Cxcr4." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1211857305.

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25

Wooding, Anita. "Antiviral efficacy of nine nucleoside reverse transcriptase inhibitors against feline immunodeficiency virus in feline peripheral blood mononuclear cells." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-182515.

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The purpose of the study reported here was to compare the antiviral efficacy against feline immunodeficiency virus (FIV) and cytotoxicity in feline peripheral blood mononuclear (PBM) cells of 9 nucleoside reverse transcriptase inhibitors (NRTIs), three of which had not been evaluated against FIV in feline cells before. PBM cells were isolated from the blood of three specific pathogen-free (SPF) cats. The cytotoxic effects of the test compounds were determined by colorimetric quantification of a formazan product resulting from bioreduction of a tetrazolium reagent by viable PBM cells. Each compound was tested in 12 concentrations ranging from 0.001 to 500 M. Uninfected cells from one SPF cat were used in these assays. PBM cells (from all three SPF cats) were infected with the molecular clone FIV pPPR and the antiviral efficacy of the test compounds was assessed using a FIV p24 antigen capture enzyme-linked immunosorbent assay. Each compound was tested in 5 concentrations ranging from 0.1 to 10 M. Cytotoxic effects in feline PBM cells were observed only at concentrations over 10 M for all 9 NRTIs. Comparison of the cytotoxic effect at the highest concentration investigated (500 M) revealed that didanosine and amdoxovir were significantly less toxic than abacavir. As no cytotoxicity was noted up to a concentration of 10 M, this was set as the highest concentration for the second part of this study investigating the anti-FIV efficacy of the test compounds. All drugs induced a dose-dependent reduction of FIV replication. When compared at the highest concentration investigated, there was no significant difference in the antiviral efficacy among the test compounds. The EC50 could not be determined as none of the test compounds achieved 50% viral inhibition. The evaluated NRTIs had low cytotoxicity against feline PBM cells and appear to be safe options for further in vivo evaluation for the treatment of FIV-infected cats. There was no evidence suggesting that the newly evaluated compounds would be superior to the existing NRTIs for reducing the FIV burden of infected cats.

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Cravo, Joana Acciaioli Pena. "Efeito do tratamento por interferão ómega de origem felina (rFeIFN-Ω) na evolução clínica de gatos naturalmente infectados com os vírus da imunodeficiência (FIV) e leucemia felinas (FeLV) e na excreção de vírus respiratórios concomitantes." Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2011. http://hdl.handle.net/10400.5/3793.

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Dissertação de Mestrado Integrado em Medicina Veterinária
O vírus da imunodeficiência felina (FIV) e o vírus da leucemia felina (FeLV) são retrovírus responsáveis por duas das doenças infecciosas mais comuns e que põem em risco o bem-estar e a vida dos gatos em todo o mundo. Os imunoestimuladores, tais como os interferões rHuIFN-α e rFeIFN-ω, são amplamente utilizados em Medicina Veterinária no tratamento de gatos com FIV e FeLV. No entanto, a administração de rHuIFN-α a felinos tem limitações devido à produção de anticorpos contra o fármaco. O rFeIFN-ω, recentemente desenvolvido, mostrou um efeito antiviral in vitro contra FIV e FeLV assim como contra calicivírus (FCV), herpesvírus (FHV), entre outros vírus felinos. Com o objectivo de estudar os efeitos do rFeIFN-ω em gatos naturalmente infectados por FIV e/ou FeLV assim como nas infecções secundárias presentes nestes animais avaliaram-se diversos parâmetros ao longo da sua aplicação. Dos parâmetros analisados o presente estudo abrange: sinais clínicos; hemogramas; parâmetros bioquímicos; proteinogramas; carga de provírus de FeLV; presença de FCV e carga viral de FHV-1 nas secreções oronasais. A 16 gatos (7 FIV+, 6 FeLV+ e 3 FIV/FeLV+), residentes na União Zoófila de Lisboa administrou-se rFeIFN-ω segundo o protocolo licenciado para o produto (3 ciclos de 5 injecções, 1MU/Kg SID SC). Aos dias 0, 10, 30 e 65 todos os gatos foram submetidos a um exame clínico e a colheitas de amostras de material biológico (sangue e secreções oronasais). 10/16 gatos melhoraram a sua sintomatologia clínica, 5/16 mantiveram a sua condição clínica e 1/16 piorou clinicamente. A carga de provírus de FeLV diminuiu em 2/6 gatos FeLV+ e em 2/3 gatos FIV/FeLV+, aumentou em 1/6 gatos FeLV+ e nos restantes manteve-se durante a terapia. A prevalência de FCV diminuiu de 14/16 gatos ao dia 0 para 0/16 ao dia 65; a carga viral de FHV-1 diminuiu em 14/16 gatos; nos restantes 2 gatos a excreção de partículas virais nunca foi detectada. As alterações observadas nos proteinogramas podem ser indicativas das vantagens da aplicação de rFeIFN-ω. O rFeIFN-ω mostrou-se útil no melhoramento da sintomatologia clínica e no controlo de infecções virais secundárias em gatos FIV+, FeLV+ e FIV/FeLV+.
ABSTRACT - Terapeutic Effects of Feline Interferon Omega (rFeIFN-ω) in the Clinical Evolution of Naturally Infected Cats with Feline Immunodeficiency (FIV) and Feline Leukemia Virus (FeLV) and in Concomitant Respiratory Virus Excretion - Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviruses responsible for two of the most common infectious diseases that endanger the well-being and the lives of cats around the world. Immunostimulating drugs such as rHuIFN-α and rFeIFN-ω are widely used in Veterinary Medicine for the treatment of FIV and FeLV positive cats but frequent administration of rHuIFN-α is limited due to the production of antibodies against the drug. The recently developed rFeIFN-ω has shown an antiviral effect in vitro against both FIV and FeLV, as well as against calcivirus (FCV), herpesvirus (FHV), amongst other feline viruses. With the aim of studying the effects of the rFeIFN-ω in naturally infected cats with FIV and/or FeLV, as well as in secondary infections, several parameters were evaluated throughout the therapy. The parameters analyzed in this study were: clinical signs; complete blood counts; biochemistry parameters; serum protein profile; FeLV proviral load; detection of FCV and FHV-1 viral load in oronasal secretions. A total of 16 cats (7 FIV+, 6 FeLV+ and 3 FIV/FeLV+) housed in a Lisbon animal shelter were subjected to the administration of rFeIFN-ω following the licenced protocol (3 cycles of 5 injections, 1MU/Kg SID SC). On days 0, 10, 30 and 65 all cats were subjected to clinical examination and to collection of biologic material samples (blood and oronasal secretions). 10/16 cats improved their clinical signs, 5/16 remained stable and 1/16 worsened their clinical signs during therapy. FeLV proviral load lowered in 2/6 FeLV+ cats and in 2/3 FIV/FeLV+ cats, it increased in 1/6 FeLV+ cats and the rest remained stable during therapy. The prevalence of FCV was 14/16 on day 0 and 0/16 on day 65; 14/16 lowered FHV-1 viral load while 2 remained negative during the treatment. Changes in protein profile may be an indicator of the benefits of rFeIFN-ω therapy. rFeIFN-ω has proved useful in the improvement of the clinical signs and in controlling concomitant viral infections in FIV+, FeLV+ and FIV/FeLV+ cats.

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Sirage, Carla Sofia Ramos Alves. "Avaliação da expressão de mediadores imunitários em gatos infectados com o vírus da Leucemia Felina (FeLV) e tratados com interferão ómega recombinante felino (rFeIFN-ω)." Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/7195.

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Dissertação de Mestrado Integrado em Medicina Veterinária
O interferão ómega felino (rFeIFN-ω) é atualmente o único interferão licenciado para uso médico-veterinário tendo-se mostrado eficaz no tratamento de gatos infectados pelo FeLV: melhora o seu estado clínico, prolonga a sua longevidade e reduz a excreção de vírus concomitantes. Contudo, o efeito do rFeIFN-ω como antiviral tem sido questionado, acreditando-se que este fármaco atue apenas ao nível da imunidade inata. Resultados publicados pelo nosso grupo reforçam esta teoria, reportando um aumento dos níveis séricos de proteínas de fase aguda, indicadores indiretos de uma estimulação da imunidade inata. Com vista a clarificar as propriedades imunomoduladoras do rFeIFN-ω, este estudo visa avaliar o efeito deste fármaco na expressão de diferentes citoquinas (IL1β, IL4, IL6, IL10, IL12p40, IFN e TNFα) na expressão da proteína MX em gatos naturalmente infectados com FeLV. Seis (6) gatos FeLV-positivos foram tratados com rFeIFN-ω segundo o protocolo licenciado (três (3) ciclos de cinco (5) injeções subcutâneas 1MU/kg aos dias 0 – 14 - 60). Antes do início do tratamento (D0) e no seu término (D65), os animais foram sujeitos a colheitas de sangue para avaliação da expressão relativa de citoquinas e da proteína Mx por PCR em tempo real. Dois dos seis (2/6) gatos expressaram IL1β, IL6, IL12p40 ao D0 e três dos seis (3/6) ao D65 (2 decresceram expressão e 1 apresentou valor residual apenas no final do tratamento). Quatro de seis (4/6) expressaram IL4 ao D0, decrescendo para valores não quantificáveis ao D65 e um de seis (1/6) expressou TNFα ao D0. Por conseguinte, dois de seis (2/6) ao D65 (um (1) decresceu expressão e um (1) apresentou valor residual apenas no final do tratamento). Apenas um (1) gato expressou IFN ao D0 e a IL10 não revelou expressão. Assim, comparando o D0 com o D65, apesar de parecer ter havido uma tendência decrescente da expressão das citoquinas medidas, não se verificaram alterações significativas. A quantificação relativa da expressão da proteína Mx também não revelou alterações estatisticamente significativas entre o D0 e D65. Este estudo sugere que apesar do rFeIFN-ω induzir uma melhoria clinica significativa dos animais tratados, a sua acção advém sobretudo de uma estimulação da imunidade inata e não de uma acção directa sob a expressão de citoquinas. Palavras-Chave: vírus da leucemia felina; vírus da imunodeficiência felina; interferão ómega recombinante felino (rFeIFN-ω).
ABSTRACT - The feline omega interferon (rFeIFN-ω) is currently the only licensed interferon for use in veterinary medicine effective in the treatment of cats infected with FeLV: improving their clinical status, prolonging their life and reducing excretion of concomitant virus. However, the effect of ω-rFeIFN as an antiviral agent has been questioned, and it is believed that this drug acts only in innate immunity. Results published by our group support this theory, reporting an increase in serum levels of acute phase proteins, indirect indicators innate immunity stimulation. To clarify the immunomodulatory properties of ω-rFeIFN, this study aimed to evaluate the effect of this drug on the expression of different cytokines (IL1β, IL4, IL6, IL10, IL12p40, IFN and TNFα) Mx protein in cats naturally infected with FeLV. Six (6) FeLV-infected cats were treated with ω-rFeIFN according to the licensed protocol (three (3) cycles of five (5) subcutaneous injections 1MU/kg on days 0 – 14 - 60). Before the start of treatment (D0) and its end (D65), the animals were subjected to blood samples collection for evaluation of the relative cytokine expression by real time PCR. Two out of six (2/6) cats expressed IL1β, IL6 and IL12p40 to D0 and three out of six (3/6) to D65 (2 decreased and 1 demonstrated residual values only at the end of treatment). Four out of six (4/6) expressed IL4 to D0, decreasing to undetectable values on D65 and one out of six (1/6) expressed TNFα on D0. Further, two out of six (2/6) on D65 (one (1) decreased the expression and in one (1) residual values were demonstrated only at the end of treatment). Only one (1) cat expressed IFN no D0 and IL10 revealed no expression. When comparing D0 with the D65, although both cytokines appeared to show a tendency to decrease expression, there were no significant modifications detected of measured. Relative quantification of the expression of Mx protein also revealed no statistically significant changes between D0 and D65.This study suggests that although the ω-rFeIFN induced a significant clinical improvement of treated cats, his action derived mainly from stimulation of innate immunity and not from a direct action on cytokine expression.

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Liu, Pinghuang. "Virus infection and evolution in the central nervous system following intracerebroventricular inoculation with Feline Immunodeficiency Virus." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-10302005-212859/.

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HIV-1 infection of the central nervous system (CNS) results in neurological impairments in subpopulation of HIV-infected individuals which range from from mild cognitive/motor disorder (MCMD) to HIV-associated dementia (HAD). HIV-1 associated neurological diseases are still a big problem even with the introduction of combined antiretroviral therapy. However the mechanisms of CNS infection and pathogenesis that lead to HAD are still not completely clear. HIV-1 CNS infection occurs soon after peripheral infection. Subsequent to infection, the CNS may act as a protected anatomical reservoir for lentiviruses and may also give rise to the development of or sequestration of unique quasispecies. The choroid plexus (ChP) has been demonstrated to be an important site for lentivirus infection and contains a mixture of viral quasispecies including both systemic and brain derived isolates. Since the appearance of viral RNA is particularly prominent in the cerebrospinal fluid (CSF), the ChP-CSF pathway may contribute to infection and viral diversity in the CNS. In the present study, we investigated lentiviral infection and evolution within the CNS by directly infusing virus into the CSF using an FIV animal model. Cell-free NCSU1 FIV or cell-associated FIV (FIV infected ChP macrophages) was directly injected into the right lateral ventricle of the brain. Negative controls were sham inoculated with uninfected ChP macrophages or cell-free culture supernatant and positive controls were infected systemically with cell-free FIV by intraperitoneal (i.p.) injection. Intracerebroventricular (i.c.v.) inoculation with cell-free FIV resulted in high levels of plasma FIV RNA detected as early as 1-2 weeks post inoculation in all 6 i.c.v. cats, and the plasma viremia preceded the detection of CSF viral RNA. Compared to i.p. cats, i.c.v. cats exhibited much higher levels of CSF FIV RNA and FIV DNA in the brain, increased ratios of CSF to plasma viral load (>1 at several time points), and a unique rebound CSF viral peak (5 of 6 cats). Infusion of FIV-infected ChP-Mac induced an acute inflammatory response and a slight suppression of the CD4+:CD8+ ratio, but failed to produce a detectable infection. After cell-free inoculation, FIV env variants, amplified by the poymerase chain reaction (PCR) and isolated using the heteroduplex tracking assay (HTA), exhibited clear compartmentalization between the CNS and periphery. Unique or enriched variants rapidly appeared in the CSF. Similar variation was seen in FIV proviral DNA isolated from cortical and subcortical brain regions. Compared to the initial viral peak in CSF, the second CSF viral peak displayed considerable change from both the first CSF peak and matched samples of plasma. FIV env diversity was highest in the CNS tissue and was unrelated to matched PBMCs collected at the same time indicating that the sequences were not due to PBMC trafficking. In addition, three unique variants were found to be selectively enriched in the CNS. Taken together, these results demonstrated that 1) CSF provides an efficient pathway for the transfer of infectious virus to the periphery, 2) virus trafficking through the CSF promotes infection of the CNS and viral diversification, 3) CSF virus may derive from both the local productive infection and blood, and 4)virus within the CNS experienced a relatively rapid and independent evolution relative to virus in the periphery.

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Sturgess, Christopher Paul. "Studies on mucosal effector mechanisms in feline immunodeficiency virus (FIV) infection in cats." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388027.

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Hora, Aline Santana da. "Micoplasmas hemotrópicos como potenciais agentes causadores de anemia em felinos domésticos." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-05092008-104907/.

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Com o objetivo de avaliar a magnitude da infecção por micoplasmas hemotrópicos nos felinos anêmicos, amostras sangüíneas de 270 felinos anêmicos (Ht≤29%) e 53 felinos saudáveis foram submetidas à exames hematológicos, bioquímicos séricos (proteína total, albumina, fosfatase alcalina, alanina aminotransferase, aspartato aminotransferase, gamaglutamil transferase, bilirrubinas, uréia e creatinina), avaliação citológica do esfregaço sangüíneo e testes moleculares para a detecção de material genético de Mycoplasma spp. Foram encontradas 25 amostras positivas no grupo dos felinos anêmicos, pela técnica de Nested-PCR utilizando-se primers que amplificam fragmentos do gene 16S rRNA dos hemoplasmas. Dentre as amostras positivas, 23 foram caracterizadas por meio de seqüenciamento como Mycoplasma haemofelis e as duas restantes como \"Candidatus Mycoplasma turicensis\" e Mycoplasma haemocanis, respectivamente. As seqüências de nucleotídeos encontradas nesse estudo estão disponíveis no GenBank, sob os números de acesso EU442616 a EU442640, sendo os números EU442629 e EU442623, referentes ao \"Candidatus M. turicensis\" e M. haemocanis, respectivamente. Nos felinos infectados por M. haemofelis a anemia foi mais intensa quando comparados aos animais anêmicos negativos para qualquer uma das espécies de micoplasmas. Quanto à bioquímica sérica, as concentrações das bilirrubinas e a atividade sérica da ALT foram maiores nos felinos infectados. Adicionalmente, com o intuito de avaliar o papel desempenhado pelos retrovírus no desenvolvimento ou agravamento da anemia causada por micoplasmas hemotrópicos, todos os felinos foram avaliados quanto à infecção pelo vírus da imunodeficiência felina (FIV) e da leucemia felina (FeLV), por meio de testes imunoenzimáticos (ELISA) para a detecção de ambos os vírus, de imunofluorescência indireta para detecção do antígeno do FeLV e de técnicas moleculares de detecção do DNA viral do FIV. Dentre os felinos saudáveis não foi observada nenhuma amostra positiva para os micoplasmas hemotrópicos e/ou retrovírus. A associação entre M. haemofelis e FIV (p=0,009) e entre o M. haemofelis e FeLV (p=0,015) , foi evidenciada. O felino infectado por \"Candidatus M. turicensis\" apresentou discreta diminuição do hematócrito e ausência de sinais de regeneração medular e o felino positivo para M. haemocanis apresentou anemia mais profunda com sinais de regeneração. No primeiro a infecção por nenhum dos retrovírus foi identificada, enquanto que o segundo apresentou co-infecção por FIV e FeLV. As informações obtidas das alterações hematológicas e bioquímicas correlacionadas à infecção pelo M. haemofelis evidenciaram o potencial patogênico dessa espécie de micoplasma hemotrópico. A disfunção imunológica resultante da infecção pelos retrovírus pode predispor à infecção por M. haemofelis, não se excluindo a possibilidade de infecção por outros hemoplasmas.
The present study aimed to evaluate the magnitude of the hemotrophic mycoplasmas infections in anemic cats. Samples from 270 anemic cats (PCV≤29%) and 53 healthy cats were submitted to hematological analysis (CBC, cytologic evaluation of blood smear), serum biochemistry (total protein, albumin, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, gama glutamil transferase, bilirubins, urea and creatinin), and molecular assays for hemoplasma DNA detection in blood samples. Among the anemic cats, 25 samples were positive by Nested-PCR for the gender Mycoplasma using primers targeting the 16S rRNA. For species identification, sequencing of the products revealed that 23 cats were infected with Mycoplasma haemofelis, one with \"Candidatus M. turicensis\" and another with M. haemocanis. The GenBank accession numbers of the nucleotide sequences derived in this study are from EU442616 to EU442640 (EU442629 and EU442623 refer to \"Candidatus M. turicensis\" and M. haemocanis, respectively). M. haemofelis-infected cats presented significantly more severe anemia and higher bilirubins concentration and ALT serum activity. Additionally, with purpose to evaluate the role play by the retrovirus in the development or aggravation of the anemia caused by hemotrophic mycoplasmas, all cats were tested for FeLV p27 antigenemia by enzyme-linked immunosorbent assay and by indirect immunofluorescence, and anti-FIV antibodies by enzyme-linked immunosorbent assay and viral DNA by Nested-PCR. None of the healthy cats presented infection with hemotrophic mycoplasmas and/or retroviruses. The association between M. haemofelis and retroviruses (FIV, p=0,009 and FeLV, p=0,015) in anemic cats was evidenced. In the \"Candidatus M. turicensis\"-infected cat, slightly decreased hematocrit with no signs of regeneration were observed; and in the M. haemocanis-infected cat anemia was severe and regenerative. In the first, retroviruses infections were not detected, whereas the second was infected with FIV and FeLV. The hematological and biochemistry abnormalities correlated to the M. haemofelis infection had evidenced the pathogenic potential of this hemoplasma species. In conclusion, immunological dysfunction resulting from retrovirus infection may predispose to M. haemofelis infection, without excluding the possibility of infection with other hemoplasma.

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31

Brown, Abigail Louise. "Investigation into the use of feline CD40 ligand as an adjuvant in a DNA vaccine against feline immunodeficiency virus." Thesis, University of Glasgow, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412964.

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32

Veiga, Rafael Guerreiro. "Clínica e cirurgia de pequenos animais." Master's thesis, Universidade de Évora, 2016. http://hdl.handle.net/10174/19245.

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Este relatório foi elaborado na sequencia do estágio curricular realizado pelo autor, ente 28 de setembro de 2015 e 28 de março de 2016, no Hospital Clínico Veterinario de la Universidad CEU Cardenal Herrera (HCV CEU-UCH), em Alfara del Patriarca, Valência, Espanha. A infeciologia foi a área da clínica médica mais representativa (28%), sendo o vírus da imunodeficiência felina (FIV) o agente infecioso registado mais frequentemente (19%). É importante reconhecer e diagnosticar esta infeção de forma a aplicar um maneio adequado aos pacientes infetados, melhorando a sua qualidade de vida e prevenindo a propagação do vírus. A infeção provocada pelo FIV raramente provoca uma síndrome severa, porém, várias alterações podem decorrer. Apesar do FIV provocar uma infeção crónica, com os cuidados adequados, os pacientes infetados poderão viver vidas longas, com uma boa qualidade de vida, e eventualmente acabar por morrer de causas não relacionadas com o FIV; Abstract: Small Animal Medicine and Surgery This report was elaborated following the externship performed by the author, between September 28th 2015 and March 28th 2016, at the Hospital Clínico Veterinario de la Universidad CEU Cardenal Herrera (HCV CEU-UCH), in Alfara del Patriarca, Valencia, Spain. The most frequent specialty field within the area of internal medicine was infectiology (28%), with feline immunodeficiency virus (FIV) being the infectious agent most frequently registered (19%). It is important to recognize and diagnose the infection caused by this agent accurately, so that the right measures of management can be applied, improving the life’s quality of the patient and reducing the risk of viral spreading. The infection by FIV rarely produces a severe syndrome, however many clinicopathologic disorders may occur. FIV causes a chronic infection, however, with the proper care, the infected cats may live long lives, with a fair quality, eventually ending up dying from causes unrelated to FIV.

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Silva, Flávio Roberto Chaves da. "Prevalência das infecções pelo vírus da leucemia viral felina e da imunodeficiência viral felina na cidade de Porto Alegre." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/12699.

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O vírus da imunodeficiência felina (FIV) é um membro da subfamília Lentivirinae da família Retroviridae. A infecção é caracterizada por imunodepressão com um declíneo progressivo dos linfócitos T CD4+, propiciando, desta maneira, o surgimento de infecções oportunistas. Já o vírus da leucemia viral felina (FeLV) pertence a subfamília Oncovirinae da família Retroviridae. Este vírus é um importante patógeno dos gatos domésticos que causa uma variedade de desordens neoplásicas e degenerativas e também apresenta distribuição mundial. O presente estudo compreendeu um levantamento da prevalência das infecções por FIV e FeLV no Município de Porto Alegre. Foram analisadas 65 amostras de gatos sadios e doentes. A detecção destas viroses foi realizada utilizando um “kit” comercial de ELISA para ambas as viroses e um protocolo de reação em cadeia da polimerase aninhada (Nested-PCR) para detecção do FIV. Os resultados demonstraram que 21,5% (14/65) dos gatos foram positivos para FIV combinado os resultados de ambos os testes, 10,8% (7/65) foram positivos para FeLV e 6,1% (4/65) foram positivos para ambos os vírus. Foram também realizados hemogramas de 48 animais, dos quais 8 apresentaram resultados positivos para FIV na Nested-PCR. Através do teste T de Student, verificou-se que não houve diferença significativa nos valores hematológicos destes animais. Conclui-se que a utilização do ELISA com a PCR dobrou a chance de detecção de gatos FIV positivos. Desta forma, a prevalência de FIV foi aproximadamente o dobro do que a de FeLV, ao contrário do que ocorre na maior parte de outros locais estudados.
Feline immunodeficiency virus (FIV) belongs to the Lentivirinae subfamily of the Retroviridae family. The infection is characterized by immunodepression and progressive decline in CD4+ T cells that may render the animal susceptible to opportunistic infections. Feline leukemia virus (FeLV) belongs to subfamily Oncovirinae of the Retroviridae family. The virus also affects domestic cats, being an important pathogen that causes a variety of neoplastic disorders and degenerative diseases. Both viruses have a worldwide distribution. The present study aims to determine the prevalence of infection with FIV and FeLV in Porto Alegre municipality. A total of 65 cats were tested, comprising healthy and sick cats. A commercial ELISA kit was used to detect anti-FIV antibodies and FeLV antigen. A nested polymerase chain reaction (Nested-PCR) was also used for FIV provirus detection. The results showed that 21.5% of the sampled cats were positive for FIV in the ELISA and Nested-PCR, 10.8% were positive for FeLV in the ELISA and 6.1% were positive for both viruses. Haemogram of 48 animals were performed but it was not found any significant association between hematologic values of FIV positive and negative animals. It was concluded that the use of ELISA and Nested-PCR increased the possibility to detect FIV positive cats. The prevalence of FIV infected cats was higher than the prevalence of FeLV positive cats, the opposite of what is normally found in studies performed in other regions.

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Zanutto, Marcelo de Souza. "Dinâmica da infecção toxoplásmica em felinos infectados pelo Vírus da Imunodeficiência Felina." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-13082007-094957/.

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Para avaliar se a dinâmica da infecção toxoplásmica em gatos infectados pelo VIF é diferente daquela que ocorre em gatos não infectados por esse retrovírus, gatos adultos infectados pelo Vírus da Imunodeficiência Felina (VIF) clade B assintomáticos (n=7) (Grupo I: VIF+TOXO+), e gatos sem a infecção viral (n=7) (Grupo III: VIF-TOXO+) foram inoculados pela via oral com cistos de Toxoplasma gondii cepa P. Os animais foram avaliados por meio do exame clínico, mensuração de anticorpos IgM e IgG anti-T. gondii pela Reação de Imunofluorescência Indireta, eliminação e quantificação de oocistos pela técnica de flutuação em solução de sacarose, leucograma, e as subpopulações de linfócitos T CD4+ e CD8+ foram mensuradas por meio da citometria de fluxo. Outros dois grupos de gatos, um apenas infectado com o VIF (n=7) (Grupo II: VIF+TOXO-) e outro não infectado com nenhum dos agentes (n=3) (Grupo IV: VIF-TOXO-), constituíram os grupos controle. O período de eliminação de oocistos e a quantidade de oocistos eliminados foram semelhantes entre os Grupos I e III, respectivamente p=1,00 e p=0,201. O período de soroconversão e a duração dos títulos de IgM e IgG também foram semelhantes, respectivamente p=0,535; p=0,789 e p=0,674; p=0,123. No entanto, os episódios febris e de apatia foram mais freqüentes entre os gatos co-infectados (Grupo I) do que entre os animais do grupo não infectado com o vírus (Grupo III), embora estes últimos tenham apresentado diarréia mais freqüente e intensa do que os primeiros. Apenas no grupo co-infectado (Grupo I) um animal desenvolveu uveíte anterior unilateral autolimitante. Exclusivamente no grupo de gatos co-infectados (Grupo I), durante todo o período experimental foi observado aumento do número de leucócitos (p=0,047), linfócitos (p=0,029) e linfócitos T CD8+ (p=0,047) em relação aos gatos do grupo infectado apenas com o T. gondii (Grupo III). O grupo de gatos infectados somente com o VIF (Grupo II) apresentou diminuição quantitativa de linfócitos T CD4+ (p=0,031) em comparação ao grupo controle não infectado com nenhum dos agentes (Grupo IV), evidenciando a ação do vírus em destruir progressivamente essa subpopulação de linfócitos. A relação de linfócitos CD4/CD8 entre os Grupos I e II, infectados pelo VIF, e os Grupos III e IV, não infectados pelo vírus, foi alterada (p<0,001 e p=0,002 respectivamente), observando-se que a infecção toxoplásmica não teve influência sobre esse parâmetro. O aumento dos linfócitos T CD8+ nos gatos co-infectados e a diminuição de linfócitos T CD4+ causada pela infecção pelo VIF podem contribuir para o desenvolvimento de manifestações clínicas mais graves nos gatos infectados por ambos os agentes infecciosos.
Asymptomatic adult cats (n=7) infected with Feline Immunodeficiency Virus (FIV) clade B (Group I: FIV+TOXO+) and normal non-infected cats (n=7) (Group III: FIV-TOXO+) were inoculated, orally with cysts of Toxoplasma gondii strain P, in order to evaluate if there is a difference in dynamics of toxoplasmic infection between cats infected with FIV and naive-FIV cats. The animals were assessed by means of physical exam, T. gondii IgM and IgG antibodies by indirect immunofluorescent reaction, shedding and quantification of oocysts using sugar centrifugation, leucogram and CD4+ and CD8+ T-lymphocytes subsets using cytometry. Others two groups of cats, one of them only infected with FIV (n=7) (Group II: FIV+TOXO-) and other non-infected (n=3) (Group IV: FIV-TOXO-) composed the control groups. The shedding and quantification of oocysts were not different between the Groups I and III, respectively p=1,00 and p=0,201. The serum convertion and the period that during of values of IgM and IgG antibodies were not different, respectively p=0,535; p=0,789 and p=0,674; p=0,123. However, fever and letargy were more frequent between cats co-infected (Group I) than the group not infected with FIV (Group III), although the latter one had presented more frequently intense diarrhea than formers. Just one cat dually infected (Group I) presented autolimitant unilateral anterior uveitis. Only cats co-infected (Group I), during all period of the experiment, presented increase in number of leukocytes (p=0,047), lymphocytes (p=0,029) and CD8+ T lymphocytes subset (p=0,047) comparing to the cats only infected with T. gondii (Group III). Only in the group FIV-infected (Group II) was observed decrease in numbers of CD4+ T lymphocytes subset (p=0,031) compared to the not infected any microrganism (Group IV), showing the virus action to destroy this lymphocyte subset slowly. The CD4/CD8 lymphocyte ratio was different between the Groups I and II, FIV-infected, from Groups III and IV, FIV-naive cats, (p<0,001 e p=0,002 respectively) showing that toxoplasmic infection did not alter this parameter. The increase number of CD8+ T lymphocyte, in dually infected cats, associated with loss of CD4+ T lymphocyte caused by FIV, can contribute for the development of more severe clinical signs in cats dually infected.

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35

Techakriengkrai, Navapon. "Investigating the role of target cell availability in the pathogenesis of feline immunodeficiency virus infection." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7429/.

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Feline immunodeficiency virus (FIV) is a naturally occurring lentivirus of domestic cats, which shares many similarities with its human counterpart, human immunodeficiency virus (HIV). FIV infects its main target cell, the CD4+ T lymphocyte, via interactions with its primary receptor CD134 (an activation marker expressed on activated CD4+ T lymphocytes), and, the chemokine receptor CXCR4. According to the different ways in which FIV isolates interact with CD134, FIV may be categorised into two groups. The first group contains strains that tend to dominate during the earlier phase of infection, such as GL8 and CPG41. These strains are characterized by their requirement for an additional interaction with the second cysteine rich domain (CRD2) of the CD134 molecule and are classified as “CRD2-dependent” strains. The second group, on the other hand, contains either laboratory-adapted isolates or isolates that emerge after several years of infection, such as PPR or the GL8 variants that emerged in cats 6 years post experimental infection and were studied in this thesis. These isolates are designated “CRD2-independent” as they can infect target cells without interacting with CRD2 of the CD134 molecule. This study provides the first evidence that FIV compartmentalisation is related to FIV-CD134 usage and the tissue availability of CD134+ target cells. In tissue compartments containing high levels of CD134+ cells such as peripheral blood and lymph nodes, CRD2-dependent viruses predominated, whereas CRD2-independent viruses predominated in compartments with fewer CD134+ cells, such as the thymus. The dynamics of CD4+CD134+ T lymphocytes at different stages of FIV infection were also described. The levels of CD4+CD134+ T lymphocytes, which were very high in the early phase, gradually decreased in the later phase of infection. The dynamics of CD4+CD134+ T lymphocyte numbers appeared to correlate with FIV tropism switching, as more CRD2-independent viruses were isolated from cats in the late phase of infection. Moreover, it was observed that pseudotypes bearing Envs of CRD2-dependent variants infected CD134+ target cells more efficiently than pseudotypes bearing Envs of CRD2-independent variants, confirming the selective advantage of CRD2-dependent variants in environments with high levels of CD134+ target cells. In conclusion, this study demonstrated that target cell types and numbers, as well as their dynamics, play important roles in the selection and expansion of FIV variants within the viral quasispecies. Improved understanding of the roles of target cells in FIV transmission and pathogenesis will provide important information required for the development of an improved, more successful protective FIV vaccine and will provide insight into the development of effective vaccines against other lentiviral infections such as HIV.

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36

Hayes, Kathleen A. "The feline immunodeficiency virus infected cat as a model of AIDS pathogenesis and antiviral therapy /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487843314697158.

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37

Azevedo, Inês Ribeiro Pereira Siborro. "Terapêutica com interferão-w em gatos infectados pelo vírus da imunodeficiência felina e/ou pelo vírus da leucemia felina : avaliação clínica, análises laboratoriais e excreção de vírus concomitantes do tracto digestivo." Master's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/5083.

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Os interferões são as proteínas da inflamação mais bem estudadas, encontram-se no mercado dois tipos de interferão: o interferão recombinante humano alfa (reHuIFN-α) e o interferão recombinante felino ómega (reFeIFN-ω). Ambos podem ser usados no tratamento dos sintomas das duas retroviroses felinas, o vírus da imunodeficiência felina (FIV) e o vírus da leucemia felina (FeLV), duas doenças infecto-contagiosas de importante expressão na prática clínica, que afectam fortemente o estado hígido dos animais infectados e que, até ao momento, não tem cura. O reHuIFN-α encontrasse no mercado a um preço acessível, no entanto, a rápida produção de anticorpos levou à criação do reFeIFN-ω, específico para a espécie felina. O reHuIFN-ω já mostrou a sua eficácia, in vitro, contra o FIV, FeLV e coronavírus felino (FCoV), entre outros vírus que afectam estes animais. Com o objectivo de estudar os efeitos deste interferão em gatos naturalmente infectados e que ainda não estejam numa fase terminal da doença, assim como da excreção de vírus concomitantes do tracto digestivo, foram avaliados os seguintes parâmetros: sinais clínicos, hemograma, análises bioquímicas, proteinograma, carga de provírus de FeLV e excreção de FCoV e o vírus da panleucopénia felina (FPV) nas fezes. Foi administrado reFeIFN-ω a 16 gatos (7 FIV, 6 FeLV e 3 co-infetados) alojados num abrigo para gatos em Lisboa; seguiu-se o protocolo licenciado para este produto – 3 ciclos de 5 injecções, 1MU/Kg, SID, SC – foram feitas as colheitas de sangue e fezes nos dias 0, 10, 30 e 65. Houve uma melhoria dos sinais clínicos em 10/16 gatos, uma manutenção em 5/16 gatos e 1/16 gato piorou os seus sinais clínicos. Nos gatos infectados com FeLV 2/6 gatos diminuíram a sua carga de provírus, 1/6 aumentou e os restantes mantiveram, nos gatos co-infetados 1/3 gatos diminuiu e os restastes mantiveram a carga de provírus de FeLV. Apenas se detectou a presença de FPV num gato ao Dia 0, sendo que no Dia 65 não foi detectada a presença de FPV em nenhum animal. A carga de FCoV diminuiu em 7/16. Os resultados do proteinograma demonstram um efeito modelador vantajoso sobre o Sistema Imunitário (SI) e não se verificaram efeitos secundários ao nível do hemograma e parâmetros bioquímicos renais e hepáticos. O reFeIFN-ω mostrou-se vantajoso no controlo dos sinais clínicos provocados pelo FIV e/ou FeLV, assim como no controlo dos vírus concomitantes do tracto digestivo.
ABSTRACT Interferon-ω therapeutic in feline imunodeficiency virus and/or feline leukaemia virus infected cats: clinical avaliation, laboraotial analysis and gastro-intestinal concomitant virus excretion - Interferons are the most studied of the inflamatory proteins, there are two types of interferons in the market: human recombinante interferon alfa (reHuIFN-α) and feline recombinante interferon omega (reFeIFN-ω). They are both used in syntomatic treatment of feline imunodefiency virus (FIV) and in feline leukaemia virus (FeLV) infected cats. These viral infections are very common in veterinary practice, inducing severe health debilitation and there is no cure for them. The low price of reHuIFN-α is na advantage, but its repeated use may cause fast antibody stimulation, so reFeIFN-ω, which i scat specific, was created to avoid this problem. reFeIFN-ω showed to be eficiente, in vitro, against FIV, FeLV and feline coronavírus (FCoV) and other feline vírus. The purpose of this study was to evaluate the Interferon ómega efect in natural infected cats, not in a terminal fase, and the concomitante gastro-intestinal excretion virus. In order to do so, clinical signs, complete blood count, biochemistry, serum protein profile, FeLV provirus load, FCoV and feline panleukopenia virus (FPV) excretion were evaluated. reFeIFN-ω was administrated to 16 cats (7 FIV, 6 FeLV and 3 co-infected) living at a Lisbon cat shelter; the licenced protocol was respected – 3 cycle of 5 injection, 1 UM/Kg, SID, SC – blood and faeces samples were collected at 0, 10, 30 and 65 days. Clinical signs improved in 10/16 cats, maintained in 5/16 cats and worsened in 1/16 cats. In FeLV infected cats, FeLV proviral load decreased in 2/6 cats, increased in 1/6 cats and remain stable in the ohter 3 cats; 1/3 co-infected cats decreased its FeLV proviral load, while the other 2/3 remain stable. FPV was detected in one cat at day 0. At day 65 all animals were negative for this virus. FCoV load decreased in 7/16 cats. The proteinograma profile revealed an importante role on the imune system modulation. The biochemistry blood analysis showed no hepatic neather kidney toxicity. reFeIFN-ω therapy seemed to contribute to the decreasing of FIV and FeLV clinical signs and in the concomitante virus control.

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38

Phadke, Anagha. "CD8+ T cell antiviral activity: mechanism of induction and the suppression of emerging feline immunodeficiency virus strains." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/5990.

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In the present studies, the essential role of inducer cells for the induction of soluble anti-viral activity against feline immunodeficiency virus (FIV) was investigated. Induction of suppression of FIV replication was found to not strictly require autologous cells and was probably not FIV specific. Suppression was maximum when the inducer cells and the effector CD8+ T cells were in contact with each other, suggesting a potential role for membrane antigen interactions and/or cytokines in the induction process. Additionally, flow cytometry analysis demonstrated a significant increase in the percentage of CD8+ B7-1+ T cells in the peripheral blood of chronically FIV infected cats as compared with uninfected cats. Examination of the FIV V3-V4 envelope sequences from PBMC, lymph nodes and spleen from six cats chronically infected from three to six years with the molecular clone of FIV-PPR did not demonstrate viral variants specific for the tissues examined, emphasizing the critical role of the initial diversity and virulence of the infecting virus inoculum. Additionally, in vitro CD8+ T cell antiviral activity demonstrated by four of the six cats could have led to the control of virus replication in vivo, resulting in the uniform viral variants observed. Infection of specific pathogen free cats with FIV-TX53, an FIV isolate that belongs to an emerging subtype more closely related to FIV clade B, demonstrated an acute stage infection characterized by lymphoadenopathy and a viral dose dependent decline of CD4+/CD8+ T cell ratios below 1 by 11 weeks post infection. Interestingly, an expansion of CD8 low population of CD8+ T cells was observed in the infected cats. The soluble antiviral activity generated from inducer T cell stimulated CD8+ T cells from FIV-A-PPR infected cats also suppressed in vitro replication of the emerging FIV-TX53 and FIV-TX078 isolates. This is the first report demonstrating that the CD8+ T cell antiviral activity is inter-clade effective among FIV strains. As the success of a FIV vaccine could be hampered by occurrence of highly divergent viral variants in the fields, the exploitation of this innate, soluble anti-FIV activity could contribute to the design of novel, safe and complementary anti-FIV therapeutic strategies.

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39

Wooding, Anita [Verfasser], and Katrin [Akademischer Betreuer] Hartmann. "Antiviral efficacy of nine nucleoside reverse transcriptase inhibitors against feline immunodeficiency virus in feline peripheral blood mononuclear cells / Anita Wooding. Betreuer: Katrin Hartmann." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1072038404/34.

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40

Haipek, Katia. "Avaliação das subpopulações de linfócitos T CD4+, linfócitos T CD8+ e da razão CD4+/CD8+ em gatos com gengivite crônica e infectados naturalmente pelo vírus da imunodeficiência dos felinos (FIV)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/10/10136/tde-25052007-143025/.

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A gengivite crônica e intratável observada em gatos infectados pelo vírus da imunodeficiência felina (FIV) é um problema bastante freqüente na clínica de pequenos animais. O papel do FIV na etiologia da estomatite persistente ainda está por ser determinado. As manifestações orais são freqüentemente os primeiros sintomas observados em pacientes humanos infectados pelo HIV e podem ser usadas como indicadores da progressão da doença. O objetivo do presente estudo foi quantificar os linfócitos T CD4+, T CD8+ e a razão CD4+/CD8+ em uma colônia de gatos com gengivite crônica e naturalmente infectados pelo FIV. Para tanto, foram utilizados 20 gatos, todos apresentando gengivite com graus variando de 1 a 4. Desse total, 10 gatos não eram infectados pelo FIV e os outros 10 felinos eram infectados pelo FIV. Utilizou-se como controle 20 gatos sem gengivite, sendo 10 infectados pelo FIV e outros 10 não infectados pelo Retrovírus. As contagens dos linfócitos T CD4+ e CD8+ foram realizadas utilizando-se a técnica de citometria de fluxo. Os resultados obtidos demonstraram que os gatos com gengivite e infectados pelo FIV apresentaram uma contagem significativamente menor de linfócitos T CD4+ quando comparado aos gatos com gengivite e não infectados pelo FIV. Não houve diferença significativa na contagem de linfócitos T CD8+ entre os gatos com gengivite, infectados ou não pelo FIV. A razão CD4+/CD8+ também se mostrou em declínio nos gatos com gengivite e infectados pelo FIV. Concluiu-se que nas condições do presente estudo, a infecção pelo FIV compromete a resposta imunológica de felino diante da inflamação gengival.
Chronic and intractable gingivitis in FIV-infected cats is a relatively common clinical problem in veterinary practice. The role of FIV in the etiology of persistent stomatitis is still undetermined. Oral manifestations often found in HIV-infected people are frequently the first clinical sign of the infection and can be considered as an indicator of the progression of the HIV infection. The purpose of this study was to evaluate the CD4+ and CD8+ T-lymphocytes count and CD4+:CD8+ ratio in a colony of cats with chronic gingivitis. To achieve these goals, a colony of twenty domestic shorthair cats was used. All cats had some degree of gingival inflammation with scores ranging from 1 through 4. Ten cats were FIV-positive and ten were FIV-negative. As a control, twenty cats without gingivitis were used (ten cats were FIV-positive and ten were FIV-negative). CD4+ and CD8+ T-lymphocytes counts were performed by means of flow cytometry in all forty cats and results compared. The results showed that cats with gingivitis and FIV-infected had a lower CD4+ T cells count than cats with gingivitis but not FIV-infected. There was no difference in CD8+ T lymphocytes count among the cats with gingivitis infected or not with the FIV. The CD4+:CD8+ ratio was lower in cats with gingivitis and FIV-infected. One can conclude that FIV infection induces immunological disorders in cats with gingival inflammation.

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41

Gupta, Soumi. "Construction and characterization of an attenuated feline immunodeficiency virus proviral DNA vaccine that co-expresses interferon gamma /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.

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42

SIDONI, Marli. "Biotecnologia IgY aplicada ao imunodiagn?stico da infec??o pelo v?rus da imunodefici?ncia felina." Universidade Federal Rural do Rio de Janeiro, 2016. https://tede.ufrrj.br/jspui/handle/jspui/2384.

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This work focused on deploying IgY technology into developing ELISA immunoenzymatic test to FIV diagnose, contributing to the establishment of a production model for a kit in the field of veterinary medicine. The first stage of this work consisted in analyzing the literature of the veterinary documents aimed to diagnose animal diseases, as stated in our current legislation. The access to both national and international optimized the enlightenment of developing parameters and method validation criteria for the development of this new product, named ELISA r-p24 IgY. The second stage consisted in establishing purification production and physicochemical characterization of the recombinant protein p24 of FIV. The biological activity maintenance was proved by way of Western Blot test with the banda presence of approximately 25 kDa, referring to the p24 protein. The third stage was to obtain IgY cat anti-IgG, derived from hens inoculation. The kinetics were monitored by ELISA and the outcome demonstrated that as of the second week, there was a gradual increase in antibody in the yolk, and remained high throughout the period of five months. Reference to the chicken 1, the average concentration was 40,1 mg/mL e for the chicken 2 was 32,2 mg/mL, throughout the period of 5 months. The fourth stage was the use of IgY technology to develop, standardize e validate the r-p24 IgY ELISA related to its use to diagnose the infection caused by FIV. The results were: 99% accuracy, 97.7% sensitivity, 99.5% specificity and 99.1% kappa index. In the fifth stage was carried out a comparative study between ELISA r-p24 IgY and ELISA r-p24 IgG, and it was demonstrated superior performance of the ELISA r-p24 IgY. The ELISA r-p24 IgY to have favorable characteristics from a commercial perspective, such as high precision and maintenance of reactivity for a minimum period of 12 months. Therefore, the above described procedure was efficient and enabled the development of a FIV test. The predominance of IgY technology may contribute to research and development of new tests, following both international regulation related to animal welfare and validation, thus boosting national development of diagnostic kits, for the benefit of human health or animal.
O objetivo deste trabalho foi aplicar a tecnologia IgY no desenvolvimento de um teste imunoenzim?tico, ELISA, para o diagn?stico do FIV, contribuindo no estabelecimento de um modelo de produ??o para um kit nacional na ?rea de medicina veterin?ria. A primeira etapa do desenvolvimento deste trabalho consistiu na revis?o da literatura dos documentos pr?prios para produtos de uso veterin?rio, destinados a diagnosticar doen?as dos animais, disponibilizados na legisla??o vigente. A consulta aos documentos nacionais e internacionais potencializou o esclarecimento de par?metros de desempenho ou crit?rios de valida??o de m?todos, para o desenvolvimento deste novo produto, denominado ELISA r-p24 IgY. A segunda etapa consistiu no estabelecimento da produ??o, purifica??o e caracteriza??o f?sico-qu?mica da prote?na recombinante p24 do FIV. A preserva??o da atividade biol?gica foi demonstrada por Western Blot com a presen?a de uma banda pept?dica de aproximadamente 25 kDa, referente ? prote?na r-p24. A terceira etapa deste trabalho, consistiu na obten??o de anticorpos IgY anti-IgG de gato, a partir da inocula??o em galinhas poedeiras. A cin?tica foi acompanhada por ELISA demonstrando um aumento gradativo do t?tulo de anticorpos na gema a partir da segunda semana, com um aumento significativo no 2? m?s, e mantendo-se elevado durante todo o per?odo de cinco meses. As concentra??es m?dias de prote?nas na galinha 1 foi de 40,1 mg/mL a partir de uma gema e na galinha 2 foi de 32,2 mg/mL por gema, no per?odo de 5 meses. A quarta etapa deste trabalho consistiu no emprego da tecnologia IgY para o desenvolvimento, padroniza??o e a valida??o do teste de Elisa r-p24 IgY para o diagn?stico da infec??o causada pelo FIV. Os resultados obtidos foram: a acur?cia de 99%, a sensibilidade de 97,7%, a especificidade de 99,5%, e o ?ndice kappa de 99,1%. Na quinta etapa deste trabalho realizou-se o estudo comparativo do ELISA r-p24 IgY frente ao ELISA r-p24 IgG, e foi demonstrado o desempenho superior no ELISA r-p24 IgY. A valida??o do ELISA r-p24 IgY mostrou caracter?sticas desej?veis para o uso comercial, tais como alta precis?o e manuten??o da reatividade por um per?odo m?nimo de 12 meses. Conclui-se que o procedimento elaborado foi eficiente e possibilitou o desenvolvimento de um teste para o diagn?stico do FIV. O dom?nio da Tecnologia IgY poder? contribuir com a pesquisa e o desenvolvimento de novos ensaios atendendo ?s normas e diretrizes nacionais e internacionais, tanto de bem-estar animal como de valida??o, impulsionando o desenvolvimento nacional de kits diagn?sticos de interesse em sa?de humana ou animal.

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43

Hellard, Éléonore. "Des concepts et méthodes associés à la co-circulation des virus dans les populations naturelles d’hôtes à la nécessité d’interdisciplinarité : l’exemple du chat et de ses virus." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10049.

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De nombreux parasites circulent dans les populations naturelles. Au sein d’un hôte, souvent pluri-infecté, ils peuvent interagir, augmentant ou réduisant le risque d’infection et les symptômes d’autres pathogènes. L’étude de ces interactions commence seulement dans les populations naturelles. Les enjeux sont cruciaux : détecter les interactions d’intérêt, estimer la probabilité de coinfection, comprendre la cocirculation des parasites. La détection des interactions sur le terrain est compliquée par la nature des données (e.g., présence-absence) et les facteurs confondants créant des associations statistiques (fausses interactions). Ce travail visait à mener une réflexion transversale sur ces interactions et le multiparasitisme, avec des applications à des données sérologiques pour 4 virus félins suivis dans des populations rurales de chats domestiques. De nouvelles méthodes de modélisation dynamique et statistique ont été développées pour prendre en compte les facteurs générant de fausses interactions (effet cumulatif de l’âge, facteurs de risque communs) et évaluer le biais des méthodes classiques. Des synergies entre 3 couples de virus félins ont été révélées. On a aussi identifié des caractéristiques comportementales et physiologiques (modes de vie, niveau de testostérone), qui, en modulant l’exposition et la sensibilité aux pathogènes, génèrent une forte hétérogénéité entre les hôtes. Enfin, une vision intégrative des systèmes hôte-parasites est indispensable pour appréhender la complexité des communautés et évaluer l’impact de la multitude d’hôtes, de parasites et d’interactions sur la coévolution, la conservation des espèces et la gestion des maladies infectieuses
Numerous parasites circulate within natural host populations. Within a host, often pluri-infected, parasites can interact, increasing or decreasing the infection risk and/or symptoms’ severity of other pathogens. Studies of such interactions only start in natural populations. Their stakes are high: detecting interactions of interest, estimating coinfection probabilities and understanding the cocirculation of parasites. The detection of interactions in the field is however complicated by the nature of data (often presence-absence) and the existence of confounding factors that can create statistical associations (false interactions). This work aimed at having a cross-cutting reflection on those interactions and on multiparasitism, with applications on a rich dataset of four feline viruses followed in rural populations of domestic cats. New dynamical and statistical modeling methods were developed to take into account factors generating false interactions (cumulative effect of age, shared risk factors) and evaluate the biases of classical methods. Synergies between three pairs of feline viruses were revealed. In addition, we identified behavioral and physiological factors (e.g., way of life, testosterone levels) that, by modulating exposition and/or susceptibility to pathogens, generate strong heterogeneity between hosts. Finally, a more integrative approach to host-parasites systems is proposed. It now appears necessary if one wants to deal with communities’ complexity and further evaluate the impact of multiple hosts, multiple parasites and their interactions on their coevolution, species conservation and infectious diseases management

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44

Kuhnt, Leah Ann Johnson Calvin M. "Magnetic Resonance Imaging of radiation-induced thymic atrophy as a model for pathologic changes in acute feline immunodeficiency virus infection." Auburn, Ala, 2008. http://hdl.handle.net/10415/1536.

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45

Mexas, Angela Marie. "CD4+CD25+ REGULATORY T CELLS ARE INFECTED AND ACTIVATED PHENOTYPICALLY AND FUNCTIONALLY DURING ACUTE INFECTION WITH FELINE IMMUNODEFICIENCY VIRUS." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-11022007-103144/.

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HIV-induced AIDS may be mediated by the activation of immunosuppressive CD4+CD25+ T regulatory cells (Tregs). Tregs have been shown to regulate CD4+ and CD8+ immune responses to HIV and FIV antigens in vitro. We tested the hypothesis that Tregs become infected and activated during the acute stage of FIV infection leading to the suppression of CD4+ T helper cell responses. Cats were experimentally infected with FIV-NCSU-1 and blood and lymph node biopsies were collected at 1 week intervals following inoculation. Real-Time PCR was used to determine plasma viremia and relative number of FIV copies in CD4+CD25+ and CD4+CD25- T cell subsets. Flow cytometry was used to assess the absolute numbers of each cell type and the expression of activation markers. Real-time RT-PCR was also used to assess relative increases in FoxP3 and TGF- mRNA levels over time. Treg suppression of IL-2 production in CD4+ T helper cells was assessed by ELISPOT assays and inhibition of cellular proliferation was assessed by incorporation of tritiated thymidine and CFSE. Our results show that peak viremia levels correlate with maximal infectivity in lymph node CD4+CD25+ populations. FIV-gag-mRNA levels are higher in CD4+CD25+ T cells than CD4+CD25- lymph node T cells. Activation of FoxP3 and increased expression of TGF1 in CD4+CD25+ cells correlates with peak plasma viremia and FIV-gag-mRNA levels in CD4+CD25+ T cells. Regulatory function can be detected in CD4+CD25+ T cells during the acute phase of FIV infection. Our findings support the hypothesis that early activation of immunosuppressor function in Treg cells may limit an effective anti-FIV response contributing to the establishment of the chronic infection and the immunodeficiency caused by this virus.

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46

Figueiredo, Andreza Soriano. "Quantificação e seqüênciamento do gene da transcriptase reversa em gatos naturalmente infectados com vírus da imunodeficiência felina tratado com AZT /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/98345.

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Orientador: João Pessoa Araújo Júnior
Banca: Lenice do Rosário de Souza
Banca: Alexandre Secorum Borges
Resumo: O Vírus da Imunodeficiência Felina (FIV) é um lentivírus que causa uma síndrome de imunodeficiência em gatos domésticos. O FIV tem sido particularmente utilizado em estudos de resistência viral aos análogos de nucleosídeos devido a Transcriptase Reversa (TR) apresentar propriedades físicas, catalíticas e sensibilidade às drogas semelhantes à TR do HIV. Os objetivos desse trabalho foram tratar com AZT gatos naturalmente infectados com o FIV, fazer o monitoramento da carga viral e DNA proviral por PCR em tempo real e monitoramento genético por seqüenciamento. Dos 12 animais infectados, 6 receberam o AZT na dose de 10mg/kg/dia e 6 receberam placebo. Durante 96 dias de tratamento, o plasma e sangue destes animais foram analisado com relação à carga viral e concentração relativa de DNA proviral utilizando-se a técnica de quantificação relativa por PCR em tempo real com SYBR Green, desenvolvida por nossa equipe. Além disso, foi realizado o sequenciamento genético da região que codifica a TR de 3 dos animais. Foi realizada com sucesso a padronização da PCR em tempo real para quantificação relativa do FIV. Não houve diferença estatisticamente significativa da carga viral ou do DNA proviral entre os grupos tratado e controle. O seqüenciamento genético revelou a presença de lisina na posição 41 do sítio ativo da TR. A presença deste aminoácido confere até 4 vezes menor sensibilidade ao AZT em mutantes do HIV. Por possuir alta estabilidade genética, supomos que os vírus dos demais animais não sequenciados possuem também a 41-lisina A presença da 41-lisina pode ser uma das possíveis explicações para a falha do tratamento com AZT. Outra hipótese é a de que a dose fornecida não foi adequada.
Abstract: Feline Immunodeficiency Virus (FIV) is a lentivirus which causes a progressive disruption of the host's immune functions. FIV has been particularly used as a model for studies in retroviral resistance to nucleoside analogs because its similarities in physical properties, catalytic and sensitivity in comparison with HIV/RT. The aims of this work were to treat cats naturally infected with FIV, quantify viral load and proviral DNA by real time quantitative PCR with SYBR Green and analyze the viral nucleotide sequence. From 12 animals naturally infected, 6 received AZT at a dose of 10mg/kg/day and 6 received placebo. During 96 days of treatment, viral load and concentration of proviral DNA were measured by relative quantitative real time PCR developed by our staff. The nucleotide sequence of the RT encoding region was also achieved for 3 animals. The real time PCR relative quantification was successfully standardized for FIV. There was no significant statistical difference between treated and control groups. The nucleotide sequence revealed a lysine at position 41 on the enzyme active site. This lysine confers 4-fold decreased sensitivity to AZT in HIV RT-mutants. FIV subtype B has high genetic stability and we purposed that the other virus not sequenced have the same amino acid and hypothesized that this mutations can be one of the reasons determining the failure of the treatment. The other hypothesis is that the dose was not adequate.
Mestre

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47

Thomas, Jan. "Feline immunodeficiency virus infection in domestic cats in Western Australia: Prevalence of natural infection and association with clinical and morphological disease." Thesis, Thomas, Jan (1997) Feline immunodeficiency virus infection in domestic cats in Western Australia: Prevalence of natural infection and association with clinical and morphological disease. PhD thesis, Murdoch University, 1997. https://researchrepository.murdoch.edu.au/id/eprint/53185/.

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A series of studies was undertaken to survey the prevalence of Feline Immunodeficiency Virus (FIV) infection in domestic cats in Western Australia and to establish the relationship between infection and states of clinical and morphological disease. The studies established that there was a high prevalence of FIV infection in sick cats in Western Australia. The historical data, clinical and clinicopathological changes affecting these animals were compared with those from sick cats unaffected by FIV. This revealed the typical disease picture seen with FIV infection in cats from Western Australia. Anaemia, lymphopaenia, azotaemia, and hyperglobulinaemia were associated with FIV infection. Similarly male cats and cats over 4 years of age were more likely to be affected by FIV infection. Clinical signs were limited to systemic signs of anorexia, weight loss, collapse, and hypothermia. Previously reported clinical signs were not confirmed when the prevalence of these signs were examined in conjunction with the prevalence in the FIV negative sick cats. The impact of FIV infection on anaemia in cats was further investigated. This incorporated examination for other reported causal agents and mechanisms that induce anaemia. Feline Leukaemia Virus (FeLV) infection was found to be the most significant infectious agent in anaemic cats. An aetiology or mechanism was identified in more than 85% of cats. Similarly, the significance of FIV infection in feline renal disease in cats was determined. The histological patterns and frequency of renal disease in cats in Western Australia was established using archival material. Prospective analysis of azotaemic cats established the clinicopathologic and clinical changes seen in each pattern of renal disease. FIV showed a trend toward association with the combined patterns of reflux nephropathy and pyelonephritis. Previously unrecognised patterns of renal disease were described.

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48

Figueiredo, Andreza Soriano [UNESP]. "Quantificação e seqüênciamento do gene da transcriptase reversa em gatos naturalmente infectados com vírus da imunodeficiência felina tratado com AZT." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/98345.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O Vírus da Imunodeficiência Felina (FIV) é um lentivírus que causa uma síndrome de imunodeficiência em gatos domésticos. O FIV tem sido particularmente utilizado em estudos de resistência viral aos análogos de nucleosídeos devido a Transcriptase Reversa (TR) apresentar propriedades físicas, catalíticas e sensibilidade às drogas semelhantes à TR do HIV. Os objetivos desse trabalho foram tratar com AZT gatos naturalmente infectados com o FIV, fazer o monitoramento da carga viral e DNA proviral por PCR em tempo real e monitoramento genético por seqüenciamento. Dos 12 animais infectados, 6 receberam o AZT na dose de 10mg/kg/dia e 6 receberam placebo. Durante 96 dias de tratamento, o plasma e sangue destes animais foram analisado com relação à carga viral e concentração relativa de DNA proviral utilizando-se a técnica de quantificação relativa por PCR em tempo real com SYBR Green, desenvolvida por nossa equipe. Além disso, foi realizado o sequenciamento genético da região que codifica a TR de 3 dos animais. Foi realizada com sucesso a padronização da PCR em tempo real para quantificação relativa do FIV. Não houve diferença estatisticamente significativa da carga viral ou do DNA proviral entre os grupos tratado e controle. O seqüenciamento genético revelou a presença de lisina na posição 41 do sítio ativo da TR. A presença deste aminoácido confere até 4 vezes menor sensibilidade ao AZT em mutantes do HIV. Por possuir alta estabilidade genética, supomos que os vírus dos demais animais não sequenciados possuem também a 41-lisina A presença da 41-lisina pode ser uma das possíveis explicações para a falha do tratamento com AZT. Outra hipótese é a de que a dose fornecida não foi adequada.
Feline Immunodeficiency Virus (FIV) is a lentivirus which causes a progressive disruption of the host's immune functions. FIV has been particularly used as a model for studies in retroviral resistance to nucleoside analogs because its similarities in physical properties, catalytic and sensitivity in comparison with HIV/RT. The aims of this work were to treat cats naturally infected with FIV, quantify viral load and proviral DNA by real time quantitative PCR with SYBR Green and analyze the viral nucleotide sequence. From 12 animals naturally infected, 6 received AZT at a dose of 10mg/kg/day and 6 received placebo. During 96 days of treatment, viral load and concentration of proviral DNA were measured by relative quantitative real time PCR developed by our staff. The nucleotide sequence of the RT encoding region was also achieved for 3 animals. The real time PCR relative quantification was successfully standardized for FIV. There was no significant statistical difference between treated and control groups. The nucleotide sequence revealed a lysine at position 41 on the enzyme active site. This lysine confers 4-fold decreased sensitivity to AZT in HIV RT-mutants. FIV subtype B has high genetic stability and we purposed that the other virus not sequenced have the same amino acid and hypothesized that this mutations can be one of the reasons determining the failure of the treatment. The other hypothesis is that the dose was not adequate.

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49

Botelho, Sílvia Maria Almeida. "Estudo epidemiológico do vírus da imunodeficiência felina e do vírus da leucemia felina em gatos errantes e assilvestrados da ilha de São Miguel, Açores." Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/6751.

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Dissertação de Mestrado Integrado em Medicina Veterinária
O vírus da Leucemia Felina (FeLV) e o vírus da Imunodeficiência Felina (FIV) pertencem à família Retroviridae. São responsáveis por duas viroses que ameaçam a vida e o bem-estar do gato doméstico, e a conservação de felinos silvestres como o lince da Península Ibérica. O principal objetivo deste estudo epidemiológico foi detetar a presença do FIV e do FeLV em gatos residentes na ilha de São Miguel, Açores. A amostra foi constituída por 90 gatos selecionados em grupos de risco elevado ou com sinais clínicos compatíveis com estas viroses, maioritariamente gatos errantes (84,4%) e assilvestrados (11,1%) que foram capturados para serem esterilizados e integrarem programas de adoção ou de restituição ao habitat. Através do teste ELISA, ViraCHECKFIV para pesquisa de anticorpos, obtivemos uma prevalência real de 14,2% de FIV na nossa amostra. Com o teste ELISA, ViraCHECKFeLV para pesquisa de antigénio, obtivemos uma prevalência real de 0,6% de FeLV na nossa amostra. Esta é a primeira publicação científica que demonstra a presença destes vírus na população felina da ilha de São Miguel. O perfil do gato infetado com FIV na amostra investigada é um gato macho, inteiro, de condição de vida livre, com um comportamento agressivo ou nervoso, com um ou mais linfonodos superficiais hipertrofiados e com gengivo-estomatite. A discussão dos resultados é feita à luz das frequências de infecção de FIV e de FeLV detetadas noutras ilhas do globo. Finalmente propõem-se medidas de controlo e de prevenção para mitigar a incidência de FIV e de FeLV e para delimitar a dispersão geográfica destas viroses na ilha de São Miguel.
ABSTRACT - EPIDEMIOLOGICAL STUDY OF FELINE IMMUNODEFICIENCY VIRUS AND FELINE LEUKEMIA VIRUS IN STRAY CATS AND FERAL CATS OF THE SÃO MIGUEL ISLAND, AZORES - The feline leukemia virus (FeLV) and the feline immunodeficiency virus (FIV) are two virus of the Retroviridae family. They are a major threat to the life and welfare of the domestic cat, and to the success of wildlife feline species conservation programs such as the Iberian lynx at the Iberian Peninsula. The main aim of this epidemiological study was to confirm the presence of FIV and FeLV in a sample of stray and feral cats of São Miguel Island in the archipelago of Azores. Ninety cats were sampled, mainly stray cats (84.4%) and feral cats (11.1%), during field operations of a trap, neuter and release or adoption program. The presence of FIV was confirmed by the ELISA test ViraCHECKFIV. The true prevalence obtained was 14.2%. The presence of FeLV was also confirmed by the ELISA test ViraCHECKFeLV. The true prevalence obtained was 0.6%. This is the first scientific communication of the presence of these viruses on the feline population of the island. The profile of the FIV infected cat is an intact male, free-roaming, with aggressive or nervous behavior, with one or more superficial lymph nodes hypertrophied and with signs of gingivostomatitis. The discussion is made by the light of the prevalence of FIV and FeLV reported on other islands in the world. Finally disease control and prevention measures are proposed to mitigate the incidence of FIV and FeLV and to restrict the geographical dispersion of these viruses in the island of São Miguel.

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50

Fernandes, Marta Freixo. "Avaliação retrospetiva da resposta ao tratamento cirúrgico da gengivo-estomatite crónica em gatos infetados com o vírus da imunodeficiência felina." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2019. http://hdl.handle.net/10400.5/18934.

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Abstract:

Dissertação de Mestrado Integrado em Medicina Veterinária
A gengivo-estomatite crónica felina é uma síndrome multifactorial que pode ocorrer em gatos infetados com o vírus da imunodeficiência felina como uma manifestação desta doença. O seu tratamento inclui diversas opções terapêuticas médicas, embora as extrações dentárias sejam a medida considerada mais eficaz até ao momento. O objetivo do presente trabalho consistiu em estudar a resposta ao tratamento cirúrgico da gengivo-estomatite crónica felina, em gatos infetados pelo vírus da imunodeficiência felina. A amostra em estudo foi constituída por 20 gatos positivos para o vírus da imunodeficiência felina com diagnóstico de gengivo-estomatite crónica, que foram submetidos a cirurgia para extração dentária dos dentes afetados (extração parcial) ou de todos os dentes (extração total), tendo sido acompanhada a evolução clínica destes gatos durante 3 meses. Os dados foram analisados estatisticamente com recurso ao Software IBM SPSS®. No fim do período, um total de 85% dos animais beneficiaram com a cirurgia, sendo que, destes 85%, 45% apresentaram melhorias significativas e 40% ficaram curados da gengivo-estomatite crónica, resultados que são semelhantes aos conhecidos para gatos não infetados com o vírus da imunodeficiência felina. Verificou-se que o uso de corticosteroides prejudica o prognóstico pós-cirúrgico (p=0,019) e que se deve evitar o uso de tratamento médico antes da cirurgia (p=0,017). Não se verificou relação entre o número de lesões que o animal apresenta (p=0,754) e o prognóstico nem entre o tipo de cirurgia (p=0,193) realizado e o prognóstico. O estudo não permitiu concluir se existe benefício do tratamento com antivíricos devido ao número reduzido de casos no qual este foi utilizado ou por não terem sido usados de forma isolada. Conclui-se que os gatos infetados pelo vírus da imunodeficiência felina respondem de forma positiva ao tratamento cirúrgico com extrações dentárias e que a realização de tratamento médico antes da cirurgia pode não ser necessário nestes animais.
ABSTRACT - Retrospective study of the Treatment response to tooth extraction surgery for chronic gingivostomatitis in cats infect with the feline immunodeficiency virus - Feline chronic gingivostomatitis is a multifactorial syndrome that appears in many cats infected with the feline immunodeficiency virus as a consequence of this disease. There are many different pharmacological therapeutics options however the tooth extraction is considered the most effective. The objective of this work is to study the response to feline chronic gingivostomatitis treatment in cats infected with the feline immunodeficiency virus. In this study 20 cats infected with feline immunodeficiency virus and with chronic gingivostomatitis diagnostic were subjected to tooth extraction surgery and then to a follow-up for 3 months after surgery. Some of them removed all of their teeth, others removed only the affected teeth. The data was analyzed using the software IBM SPSS®. At the end of the study period, a total of 85% of the cats ended up benefiting from surgery where 45% of the cats presented noticeable improvement and 40% became healed from the gingivostomatitis, which are similar results to those obtained for cats not infected with the feline immunodeficiency virus. There was detected that the use of steroids reduces de response to treatment of these cats (0,019) and that the use of medical treatment before the surgery should be avoided (p=0,017). There was no significant relation between the number of lesions (p=0,754) and the prognostic of these animals nor between the type of surgery performed (p=0,193) and the recovery of these animals. It was not able to conclude any benefit from the use of antivirals because due to the limited number of cases and due to its used being associated with other medical treatments. This study suggests that cats infected with the feline immunodeficiency virus respond favorably to tooth extraction surgery and that medical treatment before surgery may not be necessary in these cats.
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Dissertations / Theses on the topic 'Feline immunodeficiency virus'

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