Dissertations / Theses: 'Immune response genes'

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Aldred, Patricia M. R. "Variation in human immune response genes." Thesis, University of Nottingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415720.

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Lorenzi, Roberto. "Studies on gene conversion as a mutational mechanism in the evolution of major histocompatibility complex genes." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336766.

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Milner, Caroline M. "Characterisation of novel genes in the human major histocompatibility complex : the HSP70 & G9a genes." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302867.

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Ghaffari, Emma Louise Marie. "Early growth response genes -2 and -3 are essential for optimal immune responses." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/8134.

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Early Growth Response Genes (EGR) is a family of four transcription factors containing a unique zinc finger domain. EGR-2 and EGR-3 are important for hindbrain development and myelination. These transcription factors are also necessary for lymphocyte function however, the mechanisms are still unclear. Previous findings have shown that EGR-2cKO mice develop lupus-like autoimmune disease with high levels of pro-inflammatory cytokines despite showing normal T and B cell proliferation after mitogenic stimulation. Therefore we established the CD2-EGR-2-/-EGR-3-/- mouse model to explore the phenotype, susceptibility to autoimmune disease and relevant lymphocyte function. We discovered that CD2-EGR-2-/-EGR-3-/- mice developed severe systemic autoimmune disease and expressed high levels of inflammatory cytokines. More importantly we discovered a novel finding that CD2-EGR-2-/-EGR-3-/- T and B cells had impaired cell proliferation after mitogenic stimulation. Further investigations revealed that the molecular mechanism defected in the T cell receptor signalling pathway is due to a dysfunction in Activator Protein-1 (AP-1). AP-1 is a heterodimeric protein composed of AP-1 family members including Jun, Atf and Fos. Our data shows that EGR-2 and EGR-3 directly bind with the Atf family member Batf, which prevents Batf’s inhibitory function on AP-1 activation. This research demonstrates that EGR-2 and EGR-3 intrinsically regulate chronic inflammation and also positively regulate antigen receptor activation. In conclusion EGR-2 and EGR-3 are essential for providing optimal immune responses, whilst limiting inflammatory immunopathology. We propose that this new model could be used for studying autoimmune disease.

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Kendall, Elaine. "Molecular characterisation of the human major histocompatibility complex." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333402.

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O'Neill, Ann Marie Ewald Sandra J. "Polymorphism in chicken immune response genes and resistance to disease." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Fall%20Dissertations/O'Neill_Ann_48.pdf.

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Daniels, Garry D. "Cloning and characterisation of cytokine and cytokine receptor genes in rainbow trout, Oncorhynchus mykiss." Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265893.

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Convincing molecular evidence for the existence of both cytokines and their receptors in teleost fish is presented. TGF-β is present in O. mykiss encoding a 112 amino acid mature peptide. An integrin binding site (RGD) and a characteristic tetrabasic cleavage site (RKKR) are present, as is the TGF-β superfamily motif. The mature peptide has 9 conserved cysteine residues (8 of which occur in pairs) as well as two additional conserved TGF-β superfamily residues (Pro36 and Gly46). TGF-β exhibits a wide range tissue distribution including head-kidney macrophages, PBL, brain, gill and spleen tissue, and is encoded by a 2.5Kb mRNA. The trout TGF-β gene is spread over 7 exons, with an additional intron in exon 7 when compared to mammalian and avian models. Isolation of a partial sequence also reveals the presence of TGF-β in a cyprinid species. Phylogenetic analysis suggests trout TGF-β to cluster with mammalian TGF-β1 isoforms, and the avian (TGF-β4) and amphibian (TGF-β5) homologs. Neither TNF-α or TNF receptors were detected in O. mykiss at either the cellular or molecular level. The use of degenerate primers in PCR lead to the isolation of a partial sequence for O. mykiss MHC class I. A full length CXC-R gene of 1.6Kb isolated from O. mykiss displays approximately 65% identity to mammalian CXC-R4 receptors, exhibits the seven-transmembrane domain structure of the G-protein coupled receptors and a tissue-specific distribution. Characteristic superfamily motifs and a putative glycosylation site are present in the sequence. Along with the major features of the adaptive immune response such as the major histocompatibility complex (MHC), T-cell receptor (TCR) and immunoglobulin (Ig), cytokines are now shown to be present at the level of teleost fish.

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Emonts, M. "Polymorphisms in immune response genes in infectious diseases and autoimmune diseases." [S.l.] : Rotterdam : [The Author] ; Erasmus University [Host], 2008. http://hdl.handle.net/1765/14316.

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Modesto, P. "EXPRESSION PROFILE OF IMMUNE RESPONSE GENES IN GOATS WITH EXPERIMENTALLY INDUCED STAPHYLOCOCCUS AUREUS MASTITIS." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/169565.

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Counteracting infectious diseases of farm animals are an everlasting challenge in food production from livestock and preserving the health of farm animals is highly relevant to maintaining high standards of food quality. Clinical mastitis (CM) is the primary health reason for involuntary culling in dairy small ruminants and causes additional economic losses from costs of veterinary treatments. Complementary strategies are needed, since the classical prophylactic measures sometimes appear too demanding to breeders in terms of time and care, and efficient vaccination against the main pathogens is still lacking. There is evidence that Somatic Cell Count (SCC)-based selection should efficiently reduce CM incidence and currently selection strategies in cows and sheeps are based on a linear decrease of milk SCC. The effects and efficacy of SCC selection in goats are still unknown. A better understanding of the defense mechanisms affected and modified by SCC-based selection would be helpful to predict the indirect response for CM, pathogen-specific infections, and resistance to other diseases in the long term. Knowledge of these basic mechanisms will help to the design new and optimized strategies to prevent infections and, at the same time, significantly aid the improvement of food safety for the consumer. Microarray technology enables the examination of complex interactions between the host and bacterial pathogens. In dairy ruminants transcriptome profiling has enabled the identification of genes, pathways and regulatory networks activated in mammary tissues during experimental infection by various pathogens, including E. coli, S. aureus and S. uberis. Information in goats are still low and many host-pathogen interaction mechanisms have to be explained. In our study the bovine CustomArray 90K was used to evaluate the gene expression in milk somatic cells (MSCs) and blood of goats infected by S. aureus.The objectives of the present study were: (i) to identify the network of genes that becomes activated in caprine blood and MSCs in early response upon a S. aureus challenge in order to better understand the local and sistemic response and (ii) to search any difference in this immune response by using two animal groups belonging to a caprine reference family established based on founders with adverse SCC breeding values, (iii) to develop a set of internal reference genes useful to normalize RT-qPCR data in studies of gene expression in caprine MSCs. A total of 300 genes were found to be differentially expressed between 0 h and 24 h post infection and 128 genes between 0 h and 30 h post infection, with a p value < 0.01 and log2 fold change > 1.5. Among these, the majority were up-regulated. In leukocytes a total of 8 genes were up-regulated between 0h and 30h post infection with a p value < 0.01 and log2 fold change > 1.5 and 1 was down-regulated during IMI. The top up-regulated genes (5.65 to 3.16 fold change) plays an important role (i) in immune and inflammatory response (NFKB1, TNFAIP6, BASP1, IRF1, PLEK, BATF3); (ii) in the regulation of innate resistance to pathogens (PTX3); (iii) in the regulation of cell metabolism (CYTH4, SLC2A6, ARG2). The top down-regulated genes (-1.50 to –2.46 fold) included genes involved in lipid metabolism (ABCG2, FASN), chemokine, cytokine and intracellular signaling (SPPI), cytoskeleton and extracellular matrix (KRT19). No significant differences were found in the levels of the expression gene between the two group of animals. Results provided novel information into the early stage of S. aureus infection in goats. Moreover, this study provides a validated panel of optimal internal references genes which may be useful for the identification of genes differentially expressed by RT-qPCR in caprine MSCs. According to our evaluation, we recommend using G6PD and YWHAZ as reference genes to normalize gene expression data in caprine MSCs.

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MAGRO, GIADA. "BOVINE STAPHYLOCOCCUS AUREUS MASTITIS: FROM THE MAMMARY IMMUNE RESPONSE TO THE BACTERIA VIRULENCE GENES." Doctoral thesis, Università degli Studi di Milano, 2018. http://hdl.handle.net/2434/548380.

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Staphylococcus aureus (S. aureus) is one of the most important bacteria in veterinary medicine. In dairy herds, it is a contagious bacterium responsible mainly for subclinical mastitis in cattle, which frequently gives rise to persistent and chronic infection. Mastitis cause considerable economic losses due to i) decreased milk production, (ii) reduced milk quality, and (iii) treatment costs. Mastitis is also a public health problem. Indeed, the strains isolated from infected glands could produce enterotoxins. Three factors interact in mastitis: the host, the pathogen and the environment. This thesis focuses on two main aspects: the host immune response and the virulence factor of S. aureus. The first chapter of the thesis focused on the development of a new mammary gland model to study the innate immune response bacterial infection. The mammary gland is a complex organ, and the immune response is a consequence of the different cell population interactions. Continuous or primary epithelial cell lines have been extensively used to study the mammary gland immune response, but they are composed of a single cell population. Previous studies explored the tissues of lactating cows, unconsidering the possibility of an already triggered immune response. To investigate the innate immune response of the bovine mammary gland, we used an explant of healthy heifer gland. This model allowed us to: i) exclude previous exposure of the udder to microorganisms, which might have damaged the cells and/or triggered an immune response, and ii) consider the interaction of the challenging microorganism with the tissue cell populations. Our aim was to test whether this innovative model might be a valid model to investigate the innate immune response to infection. The study was carried out on 2 mm3-sections of heifer udders, in 2 consecutive trials, using LPS or LTA in the first trial and two different concentrations of S. aureus in the second. Treated and untreated sections were collected after 1h, 3h and 6h incubation; in the first trial, a final time-point at 18h was considered. The mRNA expression of TNFα, IL-1β, IL-6, IL-8 and LAP was analyzed by quantitative real-time PCR. Histological examination showed well-preserved morphology of the tissue, and apoptosis only showed a slight, not significant increase throughout the experiment. IL-1β and IL-6 were significantly up-regulated, in response to LPS or S. aureus, while TNF-α and IL-8 significantly increased only under LPS treatment. LAP expression showed a significant late increase when stimulated by LPS. The immunochemical staining of the sections demonstrated a higher number of T lymphocytes within the alveolar epithelium, in comparison with interstitial localization. Since the explants belonged to pubertal non-pregnant heifers, T cells may be regarded as resident cells, suggesting their participation in the regulation of mammary homeostasis. Therefore, applying our model would give new insights in the investigation of udder pathophysiology. The second chapter of the thesis focused on S. aureus in bovine intrammary infections. Previous literature on the S. aureus-intrammamary suggested that infection might be related to a combination of S. aureus virulence factors beyond host factors. The present study considered 169 isolates from different Italian dairy herds that were classified into four groups based on the prevalence of S. aureus infection at the first testing: low prevalence (< 5 %; LP), medium–low (5.1 - 24 %; MLP), medium–high (24.1 - 40 %; MHP) and high (> 40 %; HP). We aimed to correlate the presence of virulence genes with the herd prevalence of intramammary infections in order to develop new strategies for the control of S. aureus mastitis. Microarray data were statistically evaluated using binary logistic regression and correspondence analysis to screen the risk factors and the relationship between prevalence group and gene. The analysis showed: (1) 24 genes at significant risk of being detected in all the herds with infection prevalence >5%, including genes belonging to microbial surface components recognizing adhesive matrix molecules (MSCRAMMs), immune evasion and serine proteases; and (2) a significant correlation coefficient between the genes interacting with the host immune response and HP isolates against LP ones. These results support the hypothesis that virulence factors, in addition to cow management, could be related to strain contagiousness, offering new insights into vaccine development.

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Ahyi, Ayélé-Nati. "The role of PU.1 and IRF4 interaction in the biology and function of T helper 2 cells." Connect to resource online, 2009. http://hdl.handle.net/1805/1882.

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Thesis (Ph.D.)--Indiana University, 2009. Title from screen (viewed on August 26, 2009). Department of Microbiology and Immunology, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Mark Kaplan. Includes vita. Includes bibliographical references (leaves 107-125).

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Weyer, Jacqueline. "Immune responses against recombinant poxvirus vaccines that express full-length lyssavirus glycoprotein genes." Thesis, University of Pretoria, 2006. http://hdl.handle.net/2263/28113.

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Rabies is a fatal but preventable neurotropic disease of potentially all mammals. The disease is caused by lyssaviruses. Rabies is recognized as the 10th most common lethal infectious disease in the world, rendering it one of the most feared zoonotic diseases known to man. Nevertheless, rabies can be prevented by application of pre- or post exposure treatments. Rabies vaccines have been available since the time of Pasteur, more that one hundred years ago. Since, vaccine research focused on the development of safer and more effective vaccines. Topics of current interest in the field of rabies vaccinology were addressed in this study. A primary concern regarding the disease is human mortalities, in the range of 60 000, reported every year. Most of these are linked to exposure to rabid dogs. In addition, a great number of post exposure treatments are administered each year at great costs. Despite availability of efficacious biologics, several factors influence the optimal use and accessibility of these agents in the countries of interest, with cost and availability being the major contributing factors. A proven approach is mass oral vaccination of target animals, such as dogs, which indirectly infers protection to susceptible hosts, including man. Currently available vaccines present several disadvantages of use though, including issues of safety or doubtful stability. Safer but effective alternative vaccines that could be used in oral baits would be valuable. Here the use of two candidate host restricted poxvirus vaccine vectors were explored, particularly also in regard to oral innocuity. The construction, convenient isolation and use of a recombinant Lumpy skin disease virus (Neethling strain) expressing rabies virus glycoprotein in a mouse model were investigated. In addition, a recombinant Modified Vaccinia virus Ankara expressing rabies virus glycoprotein was prepared and tested as a vaccine in mice, dogs and raccoons. In both cases it was clear that the severe attenuation of these viruses did affect the efficacy of the recombinant vaccines in the non-permissive hosts. With the recombinant MVA a clear dosage effect could be shown, and equivalent humoral responses could only be attained at much higher titers of vaccine virus as with replication competent counterparts. Secondly, the cross-protection of rabies vaccines across the spectrum of lyssaviruses was addressed. Lyssaviruses can be divided into two groups based on sequence analysis and pathogenesis. Viruses belonging to the so-called phylogroup II, are the Mokola, Lagos and West Caucasian Bat viruses. Classic rabies biologics fail to fully protect against the viruses attributed to a lack of cross-neutralization. Here, cross-protection and cross-reactive immune responses induced by recombinant vaccinia viruses expressing rabies, Mokola or West Caucasian Bat virus glycoproteins, in single or dual combinations, were investigated. As expected, there was a lack of cross-protection of rabies and Mokola glycoprotein vaccines. There was also a clear lack of cross-protection of West Caucasian Bat virus glycoprotein vaccine and rabies and Mokola viruses. The dual antigen expressing vaccines did not appear to offer any additional protective effect in the tested model. The Mokola virus glycoprotein vaccines induced neutralizing antibody responses that significantly cross-neutralized Lagos Bat virus. Thesis (PhD (MIcrobiology))--University of Pretoria, 2007. Microbiology and Plant Pathology unrestricted

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Rajsbaum, Ricardo. "Expression of TRIM genes in different immune cells and mechanism of regulation of their expression : implications for the immune response to pathogens." Thesis, Open University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.494626.

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The tripartite motif (TRIM) proteins are important in a variety of cellular functions including antiviral activity. We systematically analyzed mRNA expression of representative TRIMs in primary mouse macrophages, myeloid and plasmacytoid dendritic cells, and a selection of CD4+ T cell subsets. These cells have different effector functions in innate and adaptive immune responses, to a large extent due to the different patterns of cytokines that they produce. Here, we defined four clusters of TRIM genes based on their selective expression in these cell subsets. The first group of TRIMs was preferentially expressed in CD4+T cells and contained the C0S-FN3 motif.

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Izadi, Shavakand Fariba. "A molecular genetic survey of immune response genes and biodiversity of industrial and non-industrial chickens." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36959.

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The current practices in industrial poultry breeding developed specialized production lines from very few breeds, resulting in reducting in genetic diversity. “Free run/free range” production systems (non-industrial) are a more recent trend in the poultry sector. Non-industrial chicken populations may differ genetically and have more diversity in disease resistance genes than industrial populations. To test this hypothesis, six chicken populations from non-industrial source; Silkies (SK), Taiwanese Cross (TC), Shiqi (SQ), Yellow Shiqi (YSQ), Yellow Wai-Chow (YW), and Agassiz Cross (AC), and industrial populations; Lohmann White (LW) and Lohmann Brown (LB), were sampled and three related experiments were carried out. First, I used 18 microsatellite markers to study genetic diversity within and among the chicken populations. The industrial population LB and the experimental cross AC which shared some common ancestors, were closely related. Non-industrial chickens SK and TC, with Chinese breed ancestry, were related to SQ, YSQ and YW. LW with White Leghorn ancestry, was not related to the non-industrial populations. Except for YSQ and SQ, STRUCTURE clustered these chicken populations to the genetically distinct groups. Secondly, I used microsatellite marker (LEI0258), situated within the Major Histocompatibility Complex (MHC) region, to reflect the genetic variability of the adaptive immune system. Results indicated that the industrial chicken populations may have less genetic variability in the MHC compared to non-industrial populations but industrial populations may have higher frequency of certain alleles that were part of their selection history against specific pathogens. Finally, I used SNP markers to examine the genetic variation in candidate genes associated with the innate immune system (ChB6, Casp-1, IAP-1, TGF-β3, BMP-7, TLR4, MD-2, IFN-γ, iNOS, IL-2, Mx1, and TVB). There was no difference between industrial and non-industrial populations in genetic variability in this immune system. The results provided partial support for the hypothesis that industrial populations may have higher resistance to specific diseases, while non-industrial populations may have higher general disease resistance. In conclusion, the results of this thesis research provided information on the genetic diversity of these chicken populations that can be used in decision making on conservation and in developing breeding stocks for free run/free range production.

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Forni, D. "HOW NATURAL SELECTION SHAPED DIVERSITY AT IMMUNE RESPONSE GENES AND AUTOIMMUNE RISK ALLELES DURING MAMMALIAN EVOLUTION." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/279118.

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ABSTRACT INTRODUCTION Genetic diversity is generated by a combination of different evolutionary processes, including mutation, genetic drift, migration, and natural selection.It is well known that natural selection acts on a specific locus\variant, whereas demographic effects act on all loci in the same way; also the selection is expected to be focused on genomic positions that have a functional role. Importantly, the selected variants targeted by selection may not only have a functional role but can correlate with predisposition or protection to some specific diseases. They can therefore be prioritized in screenings for association with diseases and infections; indeed, genetic variants that are advantageous tend to increase in frequency in the population, while deleterious mutations tend to be eliminated. To identify selection, intra and inter species approaches are usually applied; comparing orthologous genes among different species is a successful approach to detect positive selection acting over long evolutionary timescales; on the other hand, comparing genetic variation within human populations may underline more recent adaptive events. Genes related to immune system are among the most studied genes from an evolutionary point of view: it is now established that infections have been acting as a major selective pressure on humans and, most likely, on all living organisms. Thus, the interactions between hosts and pathogens have shaped the genetic diversity over time on both sides: moreover the continuous arm race between hosts and pathogens creates a competition of co-evolving genes that develop adaptations and counter-adaptations against each other. Therefore, it is important to evaluate the level of genetic variation that determines advantageous phenotypic traits to identify genomic regions/positions underlying diversity and adaptation. My first study was focused on molecules involved in the regulation of T-cell activation. The activation of T lymphocytes is a complex phenomenon that is mediated by the interaction of a number of proteins expressed on the surface of T lymphocytes and antigen presenting cells (APC).Several pathogens have evolved strategies that specifically target these genes to either invade the host or to reduce the response of the immune system. Thus, on one hand,these genes have been engaged in a constant conflict with a large number of pathogens and play a fundamental role during infections; on the other hand, genetic variation at these loci has a potential impact on the development of autoimmune and inflammatory conditions. In the second study I focused on molecules involved in the antigen processing and presentation pathway (APP).Whatever the nature of the presenting molecule, the limited dimension of its cleft makes it impossible for macro molecules to be presented: only fragments (antigens) derived from the lysis of such molecules can be nested in the cleft. This antigenic repertoire is generated by the antigen processing and presentation pathway. Another study focused on the contact system and the molecules involved in this pathway. In particular this pathway represents a link between the coagulation and inflammatory responses, two systems central to host survival in the face of tissue damage and infection. Finally, the last molecules analyzed were the proteins responsible for nucleic acids recognition and the activation of the immune response against virus and bacteria, as the RIG-I like proteins and the AIM-2 like proteins AIM OF THE WORK The aim of all the studies was to investigate the evolutionary history of the genes involved in different pathways, both at the inter- and intra- specific level, and to exploit this information to provide novel insight into the functional role of these molecules in human health and disease. Also i wanted to evaluate the history of autoimmune risk alleles and how they spread in human populations. MATERIALS AND METHODS Mammalian coding sequences were retrieved from the Ensembl website and aligned using the The RevTrans 2.0 utility. For detecting the action of positive selection I used the PAML software with different evolutionary models. Sites under selection were identified using Bayes empirical Bayes and Mixed Effects Model of Evolution analyses.Genotype Data from the Pilot 1 phase of the 1000 Genomes Project were retrieved from the dedicated website for the genes analyzed and for 1,200 randomly selected RefSeq genes (control set) for three populations with different ancestry: European, African and East Asian. These data were used to calculate nucleotide diversity parameters as well as some site frequency spectrum-based statistics. Data from the control gene set were used to calculate empirical distributions of these parameters. FST, a measure of population genetic differentiation, and the DIND test, a test based on haplotype homozygosity, were calculated for all SNPs analyzed. I calculated statistical significance of these tests by obtaining an empirical distribution for variants located within the control genes. RESULTS AND DISCUSSION In my analyses I found that genes involved in the regulation of T cell activation have represented selection targets both along mammalian evolution and during the history of human populations; I also found that variants in these genes related to human diseases to be preferential targets of pathogen-driven selection. These results showed that an allele can spread in a population because it confers higher protection against some infectious agent, indicating adaptation to infection as the underlying explanation for the maintenance of a set of autoimmune risk alleles. These result has a relevance for the hygiene hypothesis, and support the idea that human adaptation to an environment with reduced presence of pathogens has determined the spread of some risk alleles for autoimmune and inflammatory diseases. We then presented a comprehensive analysis of the selective events acting on the antigen processing and presentation pathway across different evolutionary timescales, revealing a high proportion of genes under positive selection in mammalian species. Data also indicate a continuum in selective pressure acting on different timescales for some of these genes analyzed, and we also demonstrated that the selected variants in human populations were always located within regions with regulatory function and can have a role in modulating human phenotypes. The evolutionary analysis we performed about contact system genes indicated that mammalian kininogen has been a target of long-lasting and strong selective pressures. In particular our results reinforced the possibility that kininogen plays a central role in the modulation of immune response and is a target of different pathogen species. Finally our study of two different families of nucleic acid receptors showed that a proportion of these genes have been engaged in host-virus genetic conflict leading to a continuous host–pathogen arms race scenario, and again our results provide functional information about variants that might affect immunologic phenotypes. CONCLUSIONS Results in all these studies showed how natural selection shaped diversity in different pathway involved in the immune response, and selected sites involve positions of fundamental importance to the protein function. These novel data give rise to a number of experimentally testable hypothesis concerning the role of specific sites or regions as modulators of immunological phenotypes; they also suggest caution when extrapolating results from specific experiments in model organisms, as a considerable portion of genetic diversity in these molecules has accumulated not as a result of neutral processes but in response to adaptive events.

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Denadai, Janine. "Infecção de aves (Gallus gallus domesticus) com Salmonella enterica subesp. enterica sorovar Enteritidis contendo deleções nos genes cobS, cbiA, pduC, pduD e pduE : avaliação da colonização intestinal, invasão sistêmica e resposta imune /." Jaboticabal, 2015. http://hdl.handle.net/11449/127833.

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Orientador: Angelo Berchieri Junior Coorientador: Oliveiro Caetano de Freitas Neto Banca: Marcelo Brocchi Banca: Jacqueline Boldrin de Paiva Banca: Rosemeri de Oliveira Vasconcelos Banca: Karin Werther Resumo: Salmonella Enteritidis (SE) é responsável pela maioria dos casos de infecções alimentares em seres humanos e, geralmente, está associada ao consumo de produtos de origem avícola. Nas aves, SE coloniza o intestino, podendo sobreviver utilizando como substrato o 1,2 propanodiol (1,2-Pd) disponível neste ambiente, cujo metabolismo é viabilizado pela ação da enzima propanodiol desidratase, codificada por genes do operon pdu. A enzima propanodiol desidratase necessita de cianocobalamina como cofator enzimático, a qual é codificada pelos genes cobS e cbiA. Neste estudo, utilizou-se uma estirpe de SE e duas mutantes, sendo uma com os genes pduC, pduD, pduE defectivos (SE ΔpduCDE) e outra com os genes pduC, pduD, pduE, cobS e cbiA (SE ΔcobSΔcbiAΔpduCDE) inativados, na tentativa de avaliar a importância do 1,2-Pd para a colonização intestinal e invasão de órgãos durante a infecção de aves por SE. No primeiro experimento, estimou-se as quantidades das estirpes em baço, fígado e conteúdo cecal de aves de postura de variedades vermelha e branca. Um segundo ensaio foi realizado para verificação da excreção fecal, por meio de suabes cloacais. Aliado a isso, caracterizou-se a resposta imunológica em aves SPF desafiadas com estirpes de SE acima descritas por meio da avaliação das populações de linfócitos T CD4+ e TCD8+ em fígado e tonsilas cecais e também pela quantificação de genes responsáveis pela expressão das citocinas IL-6, CCL4, CXCLi2 e IL-22 em tonsilas cecais e IL-6 e IL-18 em baço. Observou-se que as estirpes mutantes foram capazes de colonizar o intestino e invadir o baço e fígado da mesma forma que a estirpe selvagem, sendo que as aves de postura de variedade vermelha foram mais susceptíveis a infecção sistêmica. Tanto a estirpe selvagem como as mutantes estimularam o mesmo perfil de resposta imune nas aves SPF. Portanto, os genes pduC, pduD, pduE, cobS e cbiA não são necessários para... Abstract: Salmonella Enteritidis (SE) is responsible for majority of the cases of foodborne diseases in humans and usually is associated with the consumption of poultry origin products. In birds, SE colonizes the intestine and can survive using 1,2 propanodiol (1,2-Pd) as substrate. The metabolisation of the 1,2-Pd is possible by the action of propanodiol dehydratase enzyme, encoded by genes pdu operon. Cyanocobalamin, which is encoded by genes cobS and cbiA, is the cofactor required by propanodiol dehydratase. In this study, we used one SE wild type strain and two mutants, one with mutations in pduC, pduD and pduE genes (SE ΔpduCDE) and another with mutations of pduC, pduD, pduE, cobS and cbiA genes (ΔcobSΔcbiAΔpduCDE) in attempt to evaluate the importance of 1,2-Pd for intestinal colonization and invasion of organs during infection of birds. In the first experiment, bacterial counts for all strains were obtained from spleen, liver and cecal content of white and brown varieties of commercial egg-layers. In the second assay, faecal shedding of the strains was assessed by cloacal swabs. Additionaly, immunological responses were characterised by the assessment of T CD4+ and T CD8+ cell populations in liver and cecal tonsils from SPF (Specific Pathogen Free) chicks challenged with the three strains. Complementary transcripts of genes encoding the cytokines IL-6, CCL4, CXCLi2 and IL-22 in cecal tonsils, and IL-6 and IL-18 in liver were obtained for relative quantification by qRT-PCR. It was observed that SE mutant strains were able to colonise the intestine and invade spleen and liver in the same way as the wild type strain. Brown variety of birds was more susceptible to systemic infection than white birds. Furthermore, the immune response profiles triggered by the SE wild type and the two mutants in SPF chicks were very similar. Therefore, data for the present study suggest that pduC, pduD, pduE, cobS e cbiA genes would not be essencial to ... Doutor

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Denadai, Janine [UNESP]. "Infecção de aves (Gallus gallus domesticus) com Salmonella enterica subesp. enterica sorovar Enteritidis contendo deleções nos genes cobS, cbiA, pduC, pduD e pduE: avaliação da colonização intestinal, invasão sistêmica e resposta imune." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/127833.

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Made available in DSpace on 2015-09-17T15:25:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-04-06. Added 1 bitstream(s) on 2015-09-17T15:46:24Z : No. of bitstreams: 1 000845411.pdf: 3451364 bytes, checksum: 80e865130ecdaad0f2b3fd5d563d2863 (MD5) Salmonella Enteritidis (SE) é responsável pela maioria dos casos de infecções alimentares em seres humanos e, geralmente, está associada ao consumo de produtos de origem avícola. Nas aves, SE coloniza o intestino, podendo sobreviver utilizando como substrato o 1,2 propanodiol (1,2-Pd) disponível neste ambiente, cujo metabolismo é viabilizado pela ação da enzima propanodiol desidratase, codificada por genes do operon pdu. A enzima propanodiol desidratase necessita de cianocobalamina como cofator enzimático, a qual é codificada pelos genes cobS e cbiA. Neste estudo, utilizou-se uma estirpe de SE e duas mutantes, sendo uma com os genes pduC, pduD, pduE defectivos (SE ΔpduCDE) e outra com os genes pduC, pduD, pduE, cobS e cbiA (SE ΔcobSΔcbiAΔpduCDE) inativados, na tentativa de avaliar a importância do 1,2-Pd para a colonização intestinal e invasão de órgãos durante a infecção de aves por SE. No primeiro experimento, estimou-se as quantidades das estirpes em baço, fígado e conteúdo cecal de aves de postura de variedades vermelha e branca. Um segundo ensaio foi realizado para verificação da excreção fecal, por meio de suabes cloacais. Aliado a isso, caracterizou-se a resposta imunológica em aves SPF desafiadas com estirpes de SE acima descritas por meio da avaliação das populações de linfócitos T CD4+ e TCD8+ em fígado e tonsilas cecais e também pela quantificação de genes responsáveis pela expressão das citocinas IL-6, CCL4, CXCLi2 e IL-22 em tonsilas cecais e IL-6 e IL-18 em baço. Observou-se que as estirpes mutantes foram capazes de colonizar o intestino e invadir o baço e fígado da mesma forma que a estirpe selvagem, sendo que as aves de postura de variedade vermelha foram mais susceptíveis a infecção sistêmica. Tanto a estirpe selvagem como as mutantes estimularam o mesmo perfil de resposta imune nas aves SPF. Portanto, os genes pduC, pduD, pduE, cobS e cbiA não são necessários para... Salmonella Enteritidis (SE) is responsible for majority of the cases of foodborne diseases in humans and usually is associated with the consumption of poultry origin products. In birds, SE colonizes the intestine and can survive using 1,2 propanodiol (1,2-Pd) as substrate. The metabolisation of the 1,2-Pd is possible by the action of propanodiol dehydratase enzyme, encoded by genes pdu operon. Cyanocobalamin, which is encoded by genes cobS and cbiA, is the cofactor required by propanodiol dehydratase. In this study, we used one SE wild type strain and two mutants, one with mutations in pduC, pduD and pduE genes (SE ΔpduCDE) and another with mutations of pduC, pduD, pduE, cobS and cbiA genes (ΔcobSΔcbiAΔpduCDE) in attempt to evaluate the importance of 1,2-Pd for intestinal colonization and invasion of organs during infection of birds. In the first experiment, bacterial counts for all strains were obtained from spleen, liver and cecal content of white and brown varieties of commercial egg-layers. In the second assay, faecal shedding of the strains was assessed by cloacal swabs. Additionaly, immunological responses were characterised by the assessment of T CD4+ and T CD8+ cell populations in liver and cecal tonsils from SPF (Specific Pathogen Free) chicks challenged with the three strains. Complementary transcripts of genes encoding the cytokines IL-6, CCL4, CXCLi2 and IL-22 in cecal tonsils, and IL-6 and IL-18 in liver were obtained for relative quantification by qRT-PCR. It was observed that SE mutant strains were able to colonise the intestine and invade spleen and liver in the same way as the wild type strain. Brown variety of birds was more susceptible to systemic infection than white birds. Furthermore, the immune response profiles triggered by the SE wild type and the two mutants in SPF chicks were very similar. Therefore, data for the present study suggest that pduC, pduD, pduE, cobS e cbiA genes would not be essencial to ...

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Baloglu, Simge. "Applicability of vaccinia virus as cloning and expression vector for bacterial genes: mice immune responses to vaccinia virus expressing Brucella abortus and Listeria monocytogenes antigens." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/28485.

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Previous studies by our group showed that vaccinia virus recombinants expressing Brucella abortus (BA) antigens heat shock protein GroEL, 18 kDa protein and Cu/Zn SOD, were unable to induce protective immune responses against Brucella challenge. This dissertation analyzes the possible reasons for this phenomenon, by using other genes/proteins from BA and Listeria monocytogenes (LM), various shuttle plasmids (pSC65, pSC11) and immune response modulators (CpG, IL-12, B7-1). As the first objective, a vaccinia virus recombinant (WRL7/L12), expressing the BA L7/L12 gene was generated. L7/L12 ribosomal protein was used as a T-cell reactive antigen, with protective potential to Brucella challenge. The WRL7/L12 was able to express the gene of interest and induce IgG2A type antibody response, but not a protective immune response against Brucella challenge. As a control, an antigen from LM proven to induce CTL and protective immune responses, was used to test the efficacy of vaccinia virus to induce protection. A portion of hly gene, encoding partial listeriolysin (pLLO), was inserted into the same vaccinia virus stain. This recombinant (WRpLLO) was able to induce protection against a Listeria challenge. Next another vaccinia virus recombinant expressing Brucella abortus Cu/Zn SOD was analyzed. Although a variety of approaches, including the enhancement of the protein expression by the pMCO2 synthetic promoter, booster immunization, addition of the oligomer CpG adjuvant (WRSODCpG) to enhance Th1 type response, were used, the SOD recombinant failed to protect mice against Brucella challenge. Lastly, vaccinia virus produces a family of proteins that bind cytokines, chemokines and interferons to evade the host defensive systems. Therefore, a vaccinia virus strain co-expressing murine IL-12, and cofactor B7-1, were used to generate the recombinant WRIL12L7/L12. In order to further boost the induction of Th 1 type response, the adjuvant CpG was used. A similar recombinant, WRIL12pLLO, was generated with partial hly gene to serve as a positive control for protection. Mice immune responses to these recombinants, with and without adjuvant CpG, were analyzed, and compared with the recombinants generated with vaccinia strain WR. Co-expression of IL12 and B7 abrogated the protective efficacy of the vaccinia/ pLLO recombinant. Ph. D.

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Chen, Yuanneng. "Role of polymorphisms in genes affecting oxidative stress and immune response in susceptibility to alcoholic liver disease." Thesis, University of Newcastle Upon Tyne, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391248.

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Moses, Kiriana Mihi. "A whole cord model for identification of mechanisms for the antivascular effects of DMXAA." The University of Waikato, 2007. http://hdl.handle.net/10289/2488.

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Endothelial cells form the inner lining of a blood vessel and their structure and functional integrity are important in maintenance of the vessel wall and circulatory function. These cells play key roles in immune and inflammatory reactions by regulating lymphocyte and leukocyte movement into tissues; they are also main targets for antivascular agents in cancer therapy. Endothelial cell responses to different stimuli have been previously investigated using conventional approaches, 'HUVEC in vitro culture system'. In this study an ex vivo perfusion model was constructed and utilized using whole human umbilical cords, in attempts to replicate a more accurate in vivo microenvironment. Assessment of the proportion and duration of endothelial cell viability in the ex vivo model was undertaken using a MTT 3, (4,5-dimethylthiazol-2-yl) 2, 5-diphenyl-tetrazolium bromide viability assay. A time baseline was successfully established for all experimental perfusions. Endothelial cell immune response was assessed through intravenous perfusion of the endotoxin, Lipopolysaccharide (LPS). Gene expression profiles revealed a significant increase in expression levels of E-Selctin (E-Sel), Intracellular adhesion molecule (I-CAM) and Tissue Factor (TF) relative to the housekeeping gene Beta 2 Microglobulin. When LPS was administered in combination with Hypertonic Saline Solution (HSS), expression levels declined indicating HSS interferes with the activation pathway of LPS ultimately suppressing its effectiveness on endothelial cells. HSS impact was also recognized from perfusion experiments on resting endothelial cells. All identified genes were suppressed by HSS apart from inducible nitric oxide synthase (iNOS). As a potential target for antivascular agents, HUVEC were then stimulated with DMXAA and gene responses of Tumour Necrosis Factor-α (TNF-α) was analysed. DMXAA demonstrates excellent antivascular acivity in experimental tumours, so tumour conditioned media (TCM) was administered intravenously through umbilical cord segments to replicate a tumour microenvironment prior to DMXAA addition. When cells were stimulated with Tumour conditioned media then administered DMXAA, TNF-α expression was significantly upregulated; relative to the housekeeping gene Human Proteosome subunit Y, however, when the cells were exposed to tumour conditioned media in absence of DMXAA gene expression significantly decreased. Thus, the antitumour action of DMXAA is capable of inhibiting the gene response of TNF-α replicated in a tumour environment.

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Hughes, Travis Shane. "Naked plasmid DNA as a vector for delivery of genes to the intrathecal space: Expression and immune response." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337108.

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Kongchum, Pawapol. "Isolation of innate immune response genes, expression analysis, polymorphism identification and development of genetic markers for linkage analysis in common carp (Cyprinus carpio)." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/77300.

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Since the late 1990s, common carp and koi production enterprises around the world have suffered enormous losses due to a viral disease caused by cyprinid herpesvirus-3 (CyHV-3). Genetic variation in resistance to CyHV-3 infection was observed in different common carp strains, indicating that disease resistance can be improved by selective breeding. Marker-assisted selection is a breeding strategy that can accelerate genetic gain; however, this approach requires genetic markers and a genetic linkage map. To develop molecular tools for breeding CyHV-3-resistant aquaculture stock, several candidate genes for antiviral innate immune response from common carp were isolated, and single nucleotide polymorphisms (SNPs) were identified. SNP markers for common carp immune response genes were developed for testing their linkage to disease resistance and for generating a genetic linkage map. Common carp immune response genes were isolated using degenerate primers developed from conserved peptide regions among other fish species for polymerase chain reaction (PCR) amplification. The amplified products were cloned and sequenced. Gene-specific primers were designed based on the isolated carp gene sequences to amplify gene fragments from genomic DNA of three carp strains and koi. The amplified products were cloned and sequenced to identify SNPs. For the genes that are duplicated, locus-specific primers were used for PCR amplification. SNPs were identified in several genes, including TLR2, TLR3a, TLR3b, TLR4a, TLR4b, TLR7a, TLR7b, TLR9, TLR21, TLR22, MyD88a, MyD88b, TRAF6a, TRAF6b, type I IFN, IL-1β, IL10a and IL10b. Putative SNPs were genotyped in a SNP discovery panel consisting of different common carp strains and koi to evaluate their allele frequencies and in a full-sib family to validate their segregation patterns using the SNaPshot method. Validated SNPs were used to genotype a mapping family. Twenty-three SNPs (19 exonic and 4 intronic SNPs) were informative in a mapping family. Among these genes, polymorphisms in IL10a suggested a possible association with resistant and susceptible phenotypes of CyHV-3-challenged fish. These SNPs will be analyzed with a set of approximately 300 microsatellites to generate a second-generation genetic map and to identify quantitative trait loci (QTLs) affecting resistance to CyHV-3. Among the common carp genes that were isolated and sequenced, TLR9 is known for its ability to detect viral DNA and requires adaptor molecules MyD88 and TRAF6 for signal transduction. Therefore TLR9, MyD88 and TRAF6 may be important candidate genes for mediating host antiviral response to CyHV-3. To elucidate possible functions of these genes, full-length cDNAs of common carp TLR9, MyD88 and TRAF6 were isolated and tissue-specific mRNA expression was determined. cDNA sequences of MyD88 and TRAF6 revealed that these genes are duplicated. These findings were the first report of MyD88 and TRAF6 duplications in a vertebrate. Protein domain characterization demonstrated that structural characteristics of these genes are conserved and resemble those of other vertebrates, indicating that common carp TLR9, MyD88 and TRAF6 genes may have identical functions with their mammalian orthologs. The mRNA expression of TLR9, MyD88a and b, and TRAF6a and b varied among tissues. Differential expression of the MyD88 and TRAF6 paralogous transcripts were observed in muscle tissues, suggesting that one paralog has evolved and attained a non-immune function. This genomic information will facilitate further research to better understand the ligand specificity of TLR9 and the role of TLR9, MyD88 and TRAF6 in the common carp immune response. Ph. D.

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Miller, Wyatt Austin. "Effects of molting and hyposalinity stress on the expression of HIF-a, molting, and immune response genes in juvenile Cancer magister /." Connect to title online (Scholars' Bank), 2008. http://hdl.handle.net/1794/9132.

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Miller, Wyatt 1980. "Effects of Molting and Hyposalinity Stress on the Expression of HIF-a, Molting, and Immune Response Genes in Juvenile Cancer magister." Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/9132.

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xi, 49 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. Molting and hyposalinity stress in crustaceans cause extensive morphological and metabolic changes. I hypothesize that injuvenile Cancer magister, which molt in nearshore and estuarine habitats, hypoxia inducible factor (HIF) participates in regulating target genes in response to molting and hyposalinity stress. This study investigated the mRNA expression ofHIF-a, cryptocyanin 2, arthrodial membrane protein 6.0, anti.. lipopolysaccharide factor (ALF), and p-actin in juvenile C. magister under normoxic conditions. One cohort of 1st instar juveniles was maintained across the entire molt cycle. Beginning at ecdysis and daily until 2nd instar, crabs were sampled for total RNA and analyzed by real-time quantitative PCR. A second cohort was exposed to 50% seawater for 3, 8, and 24 hours and then analyzed for mRNA expression. All five genes showed molt stage-specific changes in mRNA expression during the molt cycle in normoxia, but the genes did not change expression due to hyposalinity stress. Adviser: Nora Terwilliger

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Singh, Randeep. "Early growth response genes 2 and 3 are potent inhibitors of T-bet function for interferon gamma production in T-cells." Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/14780.

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Early growth response (Egr) gene 2 and 3 are genes encoding transcription factors important for maintaining immune homeostasis. Here we define a fundamental role of Egr2 and 3 to control T cell proliferation and differentiation of effector T cells. Egr2 and Egr3 deficiency in T cells resulted in impaired T cell proliferation, but hyper-activation and excessive differentiation of T cells in response to viral infection, while, conversely, sustained Egr2 expression enhanced proliferation, but severely impaired effector differentiation in to T helper (Th) subsets, such as, Th1 and Th17 subtypes. T-bet is important for differentiation of effector T cells in response to pathogen and in particular it is a master regulator for modulating the T helper 1 lineage specific differentiation programme. Although T-bet has been extensively studied in T cells, the regulation of T-bet function is less well known. We have now discovered that Egr2 and 3 are potent inhibitors for Tbet function in CD4 and CD8 effector T cells. Together with Egr2 and 3, T-bet is induced in naïve T cells by antigen stimulation, but the expression was reciprocally regulated by IFNγ, which inhibited Egr2 and 3, but promoted Tbet expression. The expression of Egr2 and 3 in CD4 T cells under TH2 and TH17 condition was essential to suppress TH1 differentiation in vitro. In response to viral infection, sustained Egr2 expression in T cells profoundly inhibited differentiation of effector cells, while Egr2 and 3 deficient T cells produced excessive levels of IFNγ. We found that both Egr2 and 3 can directly interact with the Tbox domain of T-bet, block its DNA binding and inhibit T-bet mediated production of IFNγ. Thus, Egr2 and 3 are antagonists for T-bet function in effector T cells and essential for the control of T cell differentiation and immune pathology.

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Jusi, Márcia Mariza Gomes [UNESP]. "Estudo da resposta imune de camundongos BALB/c com a proteína recombinante A2 de Leishmania chagasi." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/126394.

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Made available in DSpace on 2015-08-20T17:09:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-12. Added 1 bitstream(s) on 2015-08-20T17:26:39Z : No. of bitstreams: 1 000837650_20170101.pdf: 129928 bytes, checksum: bcf92a65a2ae8f3fe651ecb9b7e44699 (MD5) Bitstreams deleted on 2017-01-02T15:03:50Z: 000837650_20170101.pdf,. Added 1 bitstream(s) on 2017-01-02T15:05:07Z : No. of bitstreams: 1 000837650.pdf: 3998019 bytes, checksum: 27c55eb98a37acdb1cdea68262f691ce (MD5) O agente etiológico da leishmaniose visceral no Brasil, é a Leishmania chagasi. Ela é transmitida pela picada do flebotomíneo Lutzomyia longipalpis, que adquire o parasito ao realizar o hematofagismo em animais infectados. O presente trabalho teve como objetivo estudar a resposta imune de camundongos BALB/c imunizados com a proteína recombinante produzido a partir do gene A2-L de L. chagasi, amostra isolada de um cão atendido no Hospital Veterinário da FCAV-UNESP, campus de Jaboticabal-SP, e avaliar a capacidade dessa proteína recombinante em induzir imunoproteção nos animais, após desafio com o parasito. Quarenta camundongos foram divididos em quatro grupos: G1, 10 animais inoculados com promastigotas de L. chagasi; G2, 10 animais inoculados com a proteína recombinante A2-L; G3, 10 animais imunizados com a proteína recombinante A2-L e desafiados com promastigotas de L. chagasi; G4, 10 animais inoculados com solução salina (controle negativo). Os parâmetros da resposta imune humoral avaliados foram anticorpos da classe IgG e das subclasses IgG1 e IgG2a, pelo ELISA indireto. Quanto à resposta imune celular, avaliou-se a produção de células CD4+ e CD8+, pela técnica de citometria de fluxo e, as imunomarcações de CD4+, CD8+, iNOS, macrófagos, MHC I, MHC II e Linfócitos B, pela técnica de imunohistoquímica. A produção de citocinas (IL-2, IFN-γ, TNF-α, IL-4 e IL-10), pela técnica de PCR em Tempo Real Quantitativo de Transcrição Reversa (RTqPCR) e, a carga parasitária dos baços dos camundongos infectados com o parasita por qPCR. O grupo G3 teve um padrão de resposta humoral do tipo Th1=Th2, enquanto o grupo G1, o padrão de resposta foi do tipo Th1<Th2. O grupo G3 também apresentou maior produção de linfócitos CD8 e de células expressando MHC I, MHC II e iNOS. O grupo G3 se sobressai na produção de mRNA da IL-2, do IFN-γ e do TNF-α, pelas células do baço. A carga parasitária foi... The causative agent of the disease in Brazil is Leishmania chagasi. It is transmitted by the bite of the sand fly Lutzomyia longipalpis, which acquires the parasite to realize the hematophagism in infected animals. This work aimed to study the immune response of BALB / c mice immunized with the recombinant protein produced from A2-L gene of L. chagasi, isolated sample of a dog the Veterinary Hospital of FCAV-UNESP, Jaboticabal and to evaluate the ability of this recombinant protein to induce immunoprotection in animals after challenge with the parasite. Forty mice were divided into four groups: G1, 10 animals inoculated with L. chagasi promastigotes; G2, 10 animals inoculated with the recombinant protein A2-L; G3, 10 animals immunized with the recombinant protein A2-L and challenged with promastigotes of L. chagasi; G4, 10 animals inoculated with saline (negative control). Characteristics evaluated humoral immune response were antibodies of the IgG class and IgG1 and IgG2a subclasses, the indirect ELISA. As for the cellular immune response, we evaluated the production of CD4+ and CD8+ by flow cytometry technique and evaluated the immunoblots of CD4+, CD8+, iNOS, macrophages, MHC I, MHC II and B lymphocytes, by the technique of immunohistochemistry. The production of cytokines (IL-2, IFN-γ, TNF-α, IL-4 and IL-10) by RT-PCR in real time and, the parasite load of the spleens of mice infected with the parasite by qPCR. The G3 had a pattern of humoral response Th1 = Th2, while the G1, the pattern was Th1< Th2. The G3 group also showed higher production of CD8 cells and cells expressing MHC I, MHC II and iNOS. The group G3 excels in the production of IL-2, IFN-γ and TNF-α, mRNA the spleen cells. The parasite load was significantly lower in the group G3, less than half of that found in G1. We therefore conclude that the G3 group produced a pattern of humoral and cellular responses, which according to literature suggests be effective ...

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Jusi, Márcia Mariza Gomes. "Estudo da resposta imune de camundongos BALB/c com a proteína recombinante A2 de Leishmania chagasi /." Jaboticabal, 2015. http://hdl.handle.net/11449/126394.

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Orientador: Rosangela Zacarias Machado Banca: Antonio Carlos Alessi Banca: Pamela Rodrigues Reina Moreira Banca: Hiro Goto Banca: Trícia Maria Ferreira de Sousa Oliveira Resumo: O agente etiológico da leishmaniose visceral no Brasil, é a Leishmania chagasi. Ela é transmitida pela picada do flebotomíneo Lutzomyia longipalpis, que adquire o parasito ao realizar o hematofagismo em animais infectados. O presente trabalho teve como objetivo estudar a resposta imune de camundongos BALB/c imunizados com a proteína recombinante produzido a partir do gene A2-L de L. chagasi, amostra isolada de um cão atendido no Hospital Veterinário da FCAV-UNESP, campus de Jaboticabal-SP, e avaliar a capacidade dessa proteína recombinante em induzir imunoproteção nos animais, após desafio com o parasito. Quarenta camundongos foram divididos em quatro grupos: G1, 10 animais inoculados com promastigotas de L. chagasi; G2, 10 animais inoculados com a proteína recombinante A2-L; G3, 10 animais imunizados com a proteína recombinante A2-L e desafiados com promastigotas de L. chagasi; G4, 10 animais inoculados com solução salina (controle negativo). Os parâmetros da resposta imune humoral avaliados foram anticorpos da classe IgG e das subclasses IgG1 e IgG2a, pelo ELISA indireto. Quanto à resposta imune celular, avaliou-se a produção de células CD4+ e CD8+, pela técnica de citometria de fluxo e, as imunomarcações de CD4+, CD8+, iNOS, macrófagos, MHC I, MHC II e Linfócitos B, pela técnica de imunohistoquímica. A produção de citocinas (IL-2, IFN-γ, TNF-α, IL-4 e IL-10), pela técnica de PCR em Tempo Real Quantitativo de Transcrição Reversa (RTqPCR) e, a carga parasitária dos baços dos camundongos infectados com o parasita por qPCR. O grupo G3 teve um padrão de resposta humoral do tipo Th1=Th2, enquanto o grupo G1, o padrão de resposta foi do tipo Th1<Th2. O grupo G3 também apresentou maior produção de linfócitos CD8 e de células expressando MHC I, MHC II e iNOS. O grupo G3 se sobressai na produção de mRNA da IL-2, do IFN-γ e do TNF-α, pelas células do baço. A carga parasitária foi... Abstract: The causative agent of the disease in Brazil is Leishmania chagasi. It is transmitted by the bite of the sand fly Lutzomyia longipalpis, which acquires the parasite to realize the hematophagism in infected animals. This work aimed to study the immune response of BALB / c mice immunized with the recombinant protein produced from A2-L gene of L. chagasi, isolated sample of a dog the Veterinary Hospital of FCAV-UNESP, Jaboticabal and to evaluate the ability of this recombinant protein to induce immunoprotection in animals after challenge with the parasite. Forty mice were divided into four groups: G1, 10 animals inoculated with L. chagasi promastigotes; G2, 10 animals inoculated with the recombinant protein A2-L; G3, 10 animals immunized with the recombinant protein A2-L and challenged with promastigotes of L. chagasi; G4, 10 animals inoculated with saline (negative control). Characteristics evaluated humoral immune response were antibodies of the IgG class and IgG1 and IgG2a subclasses, the indirect ELISA. As for the cellular immune response, we evaluated the production of CD4+ and CD8+ by flow cytometry technique and evaluated the immunoblots of CD4+, CD8+, iNOS, macrophages, MHC I, MHC II and B lymphocytes, by the technique of immunohistochemistry. The production of cytokines (IL-2, IFN-γ, TNF-α, IL-4 and IL-10) by RT-PCR in real time and, the parasite load of the spleens of mice infected with the parasite by qPCR. The G3 had a pattern of humoral response Th1 = Th2, while the G1, the pattern was Th1< Th2. The G3 group also showed higher production of CD8 cells and cells expressing MHC I, MHC II and iNOS. The group G3 excels in the production of IL-2, IFN-γ and TNF-α, mRNA the spleen cells. The parasite load was significantly lower in the group G3, less than half of that found in G1. We therefore conclude that the G3 group produced a pattern of humoral and cellular responses, which according to literature suggests be effective ... Doutor

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28

Sirimanapong, Wanna. "Characterisation of the immune response of the striped catfish (Pangasianodon hypophthalmus, Sauvage) following immunomodulation and challenge with bacteria pathogens." Thesis, University of Stirling, 2013. http://hdl.handle.net/1893/19277.

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In Southeast Asia, the family Pangasiidae is important for commercial fisheries and aquaculture. Pangasianodon hypophthalmus (striped catfish) is the most economically important species farmed in Vietnam, with a total export value of 1.7 billion USD in 2012. Intensive aquaculture can lead to problems with major outbreaks of disease and Edwardsiella ictaluri and Aeromonas hydrophila represent two important bacterial pathogens in P. hypophthalmus aquaculture. Immunostimulants have proven to be a very useful food additive for the aquaculture industry, since they can be easily fed to fish to enhance their immune response at times of stress and to improve resistance to disease. The immune system of pangasius catfish has not been fully described, despite the recent growth in aquaculture for this species, and little is known about the effects of immunostimulants on disease resistance. Understanding the immune response is very important in order to evaluate the health status of the fish and assist in control of disease (including prevention) so that production levels by the aquaculture industry can be sustained. The aims of this thesis were to develop and standardise methods to elucidate and measure immune responses in P. hypophthalmus and then to use these with relevant disease models (A. hydrophila and E. ictaluri) and immunomodulators (β-glucans from different sources and at different doses) to determine if bacterial diseases can be controlled, and which functional immune responses and immune genes could be correlated with disease resistance. As a variety of different species from family Pangasiidae are economically important for aquaculture, initial work focused on the characterisation of the immunoglobulin IgM molecule in these species, and anti-P. hypophthalmus IgM mAbs were tested to determine if they cross-reacted between different Pangasiidae species (Chapter 2). Although affinity purification of IgM from the different fish species resulted in a purer preparation ammonium sulphate precipitation (14% w/w), the latter proved faster and easier to perform. The heavy (H) and light (L) chains of IgM from P. hypophthalmus were estimated to be 70-72 kDa and 25-26 kDa, respectively, using SDS-PAGE (12.5%). The L chains of IgM in the other Asian fish species examined were similar in molecular weight to P. hypophthalmus, while the H chains varied (P. gigas and P. larnaudii 76kDa, P. sanitwongsei 69kDa, H. filamentus 73kDa, P. borcoti and H. wyckioides 75kDa, C. bactracus 74kDa, C. macrocephalus 73kDa and C. carpio 70kDa), as did the native IgM molecules. Sedimentation velocity ultracentrifugation was used to determine the molecular weight of the whole IgM molecule from P. hypophthalmus as an alternative to the more commonly used native gels that are run under non-denaturing conditions, although this technique proved more complex. Anti–P. hypophthalmus IgM monoclonal antibodies (mAbs) cross reacted with all of the Pangasiidae species and were successfully applied in an enzyme-linked immunosorbent assay (ELISA) using mAb 23 to measure serum antibody response of P. hypoophthalmus following experimental infection with A. hydrophila by interperitoneal (I.P.) injection in Chapter 3 and E. ictaluri by immersion in Chapter 4. As P. hypophthalmus is a relatively new aquaculture species, there are few reports evaluating its immune response to pathogens. Thus, functional assays were standardised to evaluate both innate and adaptive immune responses of this species and then these assays used to compare immune response following stimulation with live and killed A. hydrophila. (Chapter3). Four treatment groups of 40 fish per group (53.2 ± 14.8g.) consisting of an untreated control group, a group injected I.P. with adjuvant (Montanide ISA 760 VG) only, a group injected with heat-killed A. hydrophila (1 x109 cfu ml-1 mixed with adjuvant), and a group injected with a subclinical dose of live A. hydrophila 2.7 x105 cfu ml-1 were used in the study. Samples were collected 0, 1, 3, 7, 14 and 21 days post injection (d.p.i.) to assess the immune response of fish. The results indicated that challenge with live or/and dead bacteria stimulated the immune response in P. hypophthalmus significantly above control groups with respect to specific antibody titre, lysozyme activity, phagocytosis and plasma peroxidase at 7 or/and 14 d.p.i. Moreover, on 21 d.p.i. total IgM, specific antibody titre and lysozyme activity from both live and dead A. hydrophila challenge groups were significantly different to the control groups. Differential immune responses between live and dead bacterial challenges were also observed as only live A. hydrophila significantly stimulated WBC counts and plasma peroxidase at 3 d.p.i. with the greatest increase in WBC counts noted at 21 d.p.i. and in phagocytosis at 14 d.p.i. By 21 d.p.i. only the macrophages from fish challenged with dead A. hydrophila showed significantly stimulated respiratory burst activity. Immunostimulants are food additives used by the aquaculture industry to enhance the immune response, and β-glucan is now commonly used for this purpose in aquaculture. In Chapter 4 the effect of the prebiotic β-glucan on the immune response and disease resistance of P. hypophthalmus was evaluated. The fish (60.3 ± 11.7 g.) were fed with a basal diet (control) or diets supplemented with fungal derived β-glucan at concentrations of 0.05 %, 0.1 %, or 0.2 % g/kg for four weeks. Fish fed 0.1 % commercial yeast derived β-glucan were also included as a positive control group. Samples were collected from fish on Days 0, 1, 3, 7, 14, 21 and 28. The results showed that fish fed with the highest two levels of fungal derived β-glucan had enhanced immune responses compared to the control group, with respiratory burst activity on all days examined and lysozyme activity on 7 days post feeding (d.p.f.) being significantly elevated (P<0.05) in the group fed with 0.2 % fungal derived β-glucan, while plasma anti-protease activity on 21 d.p.f., natural antibody titre on 3 d.p.f. and complement activity 7 d.p.f. and 14 d.p.i. were significantly enhanced (P<0.05) in the group fed 0.1 % fungal derived β-glucan. The lowest dose of fungal derived β-glucan (0.05 %) appeared insufficient to effectively stimulate the fish’s immune response. WBC count, respiratory burst, lysozyme activity and complement were useful as an early indication of immunostimulation (1 to 7 days). Four weeks after feeding with the different diets, the fish were experimentally infected with E. ictaluri by immersion using 8 x104 cfu ml-1 for 1 h and mortalities were monitored for 14 days. There was a great deal of variation in the level of mortalities within the four replicate tanks for each dietary group. Although the in vivo challenge results showed no statistical differences between the groups fed on the different diets, the highest mortalities were observed in group fed with the control diet and the lowest mortalities were observed in the groups fed with commercial yeast derived β-glucan and 0.2 % fungal derived β glucan. Immune gene expression following stimulation with β-glucan and challenge with E. ictaluri was investigated in Chapter 5.

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Janse, van Rensburg Marike. "The role of the cytochrome B and cytochrome C oxidase III genes in the immune response of the South African abalone, Haliotis midae." Master's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/4275.

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Includes abstract. Includes bibliographical references (leaves 80-89). Although South Africa is the second largest producer of abalone outside Asia, the sustainability of the industry could be threatened by infectious diseases (Troell et ai., 2006). Probiotics are increasingly being viewed as an alternative to chemical and antibiotic treatments (Balcazar et al., 2006), and have been shown to improve the health of the South African abalone, Haliotis midae (Macey and Coyne, 2005). In order to establish better health management systems, and to implement alternative therapies such as probiotics, a better understanding of how the abalone immune system functions, and specifically how it responds to stimulation, is necessary. Two genes of the electron transport system, cytochrome b and cytochrome c oxidase III, were found to be upregulated in a cDNA microarray experiment performed on haemocytes from immunestimulated abalone (Arendze-Bailey, unpublished). The current study sought to confirm these results by semi-quantitative PCR and to further elucidate the roles of these genes, and thus the electron transport system, in the abalone immune response.

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Hippolito, Daise Damaris Carnietto de. "Estudo dos genes codificadores de citocinas implicadas na modulação da leishmaniose tegumentar americana e correlação com os achados clínico-laboratoriais da doença." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/99/99131/tde-09112017-152754/.

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A resposta imune desencadeada em pacientes com leishmaniose tegumentar Americana (LTA) é predominantemente celular. Assim, o estudo dos mecanismos imunológicos responsáveis pela formação, progressão e cura desta infecção é de grande importância, considerando a deformação que ela pode causar em indivíduos infectados. Este estudo investigou a expressão de mRNA de IFN-?, IL-10, IL-27, TNF-?, TGF-? e IL-6 em 40 biopsias de parafina (FFPE) fixadas em formalina de pacientes com diagnóstico clínico e laboratorial para LTA. Um grupo de 10 biópsias FFPE coletadas de pacientes com diagnóstico clínico de leishmaniose mucosa (LM) foi utilizado para o controle da evolução da infecção. Inicialmente, foi padronizado a extração de RNA, a síntese de cDNA e a escolha do gene endógeno em 9 biopsias frescas e 8 FFPE. Após essas padronizações, as moléculas de RNA de fragmentos de biopsias parafinadas, foram extraídas com kit específico, tratadas com DNase, quantificadas por fluorimetria e sintetizadas para cDNA. A expressão relativa de cada citocina foi determinada (em duplicata) por PCR em tempo real. As reações foram normalizadas frente ao padrão de expressão do gene endógeno GAPDH, que foi previamente padronizado. O padrão de expressão de cada gene alvo foram determinados segundo a fórmula do \"CT comparativo\" (2-??CT), na qual calcula-se quantas vezes mais ocorre a expressão do gene alvo em relação a indivíduos normais. Também incluído nesse estudo 5 amostras de biopsia de pele de indivíduos normais (grupo IV). Os resultados foram expressos em média de quantificação relativa, a análise estatística foi realizada utilizando foi determinada por Teste t não pareado e teste F para comparação de variâncias, onde três grupos de pacientes foram formados. Grupo I, 35 pacientes com LTA, cuja expressão relativa de IFN-? foi inferior a 100. Grupo II, 5 pacientes com LTA cuja expressão relativa de IFN-? foi superior a 100. Grupo III, 10 pacientes com leishmaniose mucosa. Os níveis de expressão para IFN-? foram 33,34; 214,1 e 129,6 vezes maiores para os Grupos I, II e III, respectivamente do que as amostras do controle normal. Para o TNF-? foram 11,22; 2,37 e 4,59 vezes superiores ao normal nos Grupos I, II e III, respectivamente. Para IL-10 foram 5,14; 11,54 e 2,51 vezes superiores aos valores normais nos Grupos I, II e III, respectivamente. Para IL-27 foram 15,81; 85,29 e 17,29 vezes superiores ao normal nos Grupos I, II e III, respectivamente. Para o TGF-? foram 5,38; 4,33 e 4,72 vezes superiores ao normal nos Grupos I, II e III, respectivamente. Para a IL-6 foram 5,92; 5,69 e 2,09 vezes superiores aos valores normais nos Grupos I, II e III, respectivamente. Estes resultados foram semelhantes a resultados de estudos que analisam a expressão de citocinas já sintetizadas. No geral, os resultados de expressão gênica das citocinas estudadas sugerem que a exacerbação da resposta imune do perfil Th1 (IFN-?) poderia levar ao surgimento de lesões mais graves nos pacientes dos Grupos II e III. Os níveis elevados de mRNA de IL-10, observado nos pacientes do Grupo II podem promover baixa ativação macrofágica, colaborando com a replicação do parasita e assim culminar com a progressão da doença. A expressão de mRNA de IL-27 não interferiu na expressão de mRNA de IFN-? nas células dos pacientes com leishmaiose tegumentar ou leishmaniose mucocutânea. Em conclusão, estes resultados podem sugerir que os pacientes do Grupo II podem desenvolver formas mais graves de LTA quando comparados aos do Grupo I. The immune response triggered in patients with American cutaneous leishmaniasis (ACL) is predominantly cellular. Thus, the study of the immunological mechanisms responsible for the formation, progression and cure of this infection is of great importance, considering the deformation that it can cause in infected individuals. This study investigated the expression of IFN-?, IL-10, IL-27, TNF-?, TGF-? and IL-6 mRNA in 40 formalin-fixed paraffin-embedded paraffin biopsies (FFPE) from patients with clinical and laboratory diagnosis for LTA. A group of 10 FFPE biopsies collected from patients with clinical diagnosis of mucosal leishmaniasis (MCL) was used to control the evolution of the infection. Initially, RNA extraction, cDNA synthesis and the choice of the endogenous gene were standardized in 9 fresh biopsies and 8 FFPE. After these standardizations, the RNA molecules of fragments of paraffin-shaped biopsies were extracted with a specific kit, treated with DNase, quantified by fluorimetry and synthesized for cDNA. The relative expression of each cytokine was determined (in duplicate) by real-time PCR. Reactions were normalized against the expression pattern of the endogenous GAPDH gene, which was previously standardized. The expression pattern results for each target gene were determined by the \"comparative CT\" (2-??CT) formula, in which it is calculated how many times more the expression of the target gene occurs in relation to normal individuals. Also included in this study 5 skin biopsy samples from normal subjects (group IV). The results were expressed as mean relative quantification, statistical analysis was performed using was determined by unpaired t test and F test for comparison of variances, where three groups of patients were formed. Group I, 35 patients with ACL, whose relative expression of IFN-? was less than 100. Group II, 5 patients with ACL whose relative expression of IFN-? was greater than 100. Group III, 10 patients with mucosal leishmaniasis. The expression levels for IFN-? were 33,34; 214,1 and 129,6 times higher for Groups I, II and III, respectively than the samples from the normal control. For TNF-? were 11,22; 2,37 and 4,59 times higher than normal in Groups I, II and III, respectively. For IL-10 were 5,14; 11,54 and 2,51 times higher than the normal values in Groups I, II and III, respectively. For IL-27, 15,81; 85,29 and 17,29 times higher than normal in Groups I, II and III, respectively. For TGF-? were 5,38; 4,33 and 4,72 times higher than normal in Groups I, II and III, respectively. For IL-6 were 5,92; 5,69 and 2,09 times higher than the normal values in Groups I, II and III, respectively. These results were similar to the results of studies that analyze the expression of cytokines already synthesized. In general, the gene expression results of the cytokines studied suggest that the exacerbation of the Th1 profile (IFN-?) immune response could lead to more serious lesions in patients in Groups II and III. Elevated levels of IL-10 mRNA observed in Group II patients may promote low macrophage activation, assisting in the replication of the parasite and thus culminating in the progression of the disease. Expression of IL-27 mRNA did not interfere in the expression of IFN-? mRNA in the cells of patients with tegumentary leishmaiosis or mucocutaneous leishmaniasis. In conclusion, these results may suggest that patients in Group II may develop more severe forms of ACL when compared to those in Group I.

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Sukkar, Dani. "Role of Nosema cerenae and pesticides on the decline of bees : Studies using a multifactorial approach : “Tipping the scale of honeybee immune responses - The effect of pesticides on immune-stimulation mimicking Nosema spp.”." Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0086.

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Les abeilles sont confrontées à la menace mondiale du syndrome d'effondrement des colonies (CCD), entraînant des décès de colonies et une diminution de leur nombre, affectant leur contribution environnementale et agronomique dans la pollinisation des plantes et des cultures commerciales, en plus de la production de miel. L'exposition aux pesticides peut être l'une des principales causes conduisant au CCD en affaiblissant le système immunitaire des abeilles et en altérant leurs réponses immunitaires. Les maladies de la nosémose causées par Nosema spp. peuvent avoir une contribution significative au CCD lorsque les abeilles sont exposées à différents pesticides simultanément. Dans cette étude, plusieurs facteurs de risque sont évalués, y compris les néonicotinoïdes les plus utilisés dans le monde, l'imidaclopride et l'amitraz qui est le pesticide utilisé directement en contact avec les abeilles pour traiter l'infection par les acariens. L'effet de ces pesticides est évalué au niveau de la stimulation immunitaire par zymosan A pour imiter l'infection par Nosema. L'effet des pesticides sur les produits cellulaires antimicrobiens, les réponses cellulaires et l'expression de gènes connexes est démontré Honeybee are facing the global threat of colony collapse disorder (CCD) leading colony deaths and decline in their numbers affecting their environmental and agronomic contribution in pollination of plants and commercial crops in addition to honey production. Pesticide exposure may be of the main causes leading to CCD by weakening the immune system of honeybees and impairing their immune responses. Nosemosis diseases caused by Nosema spp. may have a significant contribution to CCD when bees are exposed to different pesticides simultaneously. Multiple risk factors are assessed in this study including the most used neonicotinoids worldwide, imidacloprid and amitraz which is the pesticide used directly in contact with honeybees to treat mite infection. Th effect of these pesticides is evaluated at the level of immune stimulation by zymosan A to mimic Nosema infection. The effect of pesticides on antimicrobial cells products, cellular responses and related genes' expression are demonstrated

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32

Morampudi, Vijay. "Study of the modulation of innate immune responses in intestinal epithelial cells by Toxoplasma gondii and its correlation with parasite virulence." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210009.

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Early innate response of intestinal epithelial cells is the first line defense against enteric pathogens. Toxoplasma gondii infections acquired naturally via the peroral route, encounter intestinal epithelial cells early post-infection. Although the population structure of T. gondii is known to be highly clonal, clinical strains of T. gondii have been classified into three genotypes based on their virulence. In this study we investigated whether human intestinal epithelial cell immune response to T. gondii is virulence dependent. We demonstrated distinct virulence of the three T. gondii genotype strains evaluated in human intestinal epithelial cells by their capacity to replicate and induce host cell cytotoxicity. The early host innate mechanisms such as activation of signaling pathways and induction of innate effectors were likewise differentially elicited by the three T. gondii strains. Low levels of TLR dependent NF-kB activation and a failure to rapidly up-regulate innate cytokine and chemokine genes was observed after virulent Type I strain infection. In contrast, early innate response to the less virulent Type II strain was rapid, efficient and led to high levels of IL-8 and IL-6 secretion, whereas response to Type III parasites was intermediate. Early expression of b-defensin 2 gene was suppressed specifically by virulent Type I strain and its activation prior to infection in intestinal epithelial cells led to decreased parasite viability. These findings provide evidence for T. gondii strain virulence dependent down-modulation of early human intestinal epithelial cell innate responses and highlight the importance of these cells in host defense against this infection. Doctorat en Sciences biomédicales et pharmaceutiques info:eu-repo/semantics/nonPublished

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Ullastres, i. Coll Anna. "Adaptation in Drosophila melanogaster Natural Populations. Fitness Effects and Evolutionary History of a Natural Insertion and Molecular Effects of Several Transposable Elements on Immune-Related Genes." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/406957.

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A major challenge of modern Biology is elucidating the genetic basis of adaptation. While there are many SNP-based studies trying to elucidate the genetic basis of genotype-phenotype relationships, the role of transposable element (TE)-induced mutations is understudied. Recent evidences demonstrate that TEs are a powerful tool to identify the genetic basis of adaptive phenotypic traits. Drosophila melanogaster is a good model to study adaptation because it is original from subtropical Africa and only recently colonized out-of-Africa environments. To identify and characterize the role of several candidate TEs in D. melanogaster adaptation, we have followed two different strategies: locus-specific and trait-specific. In the first chapter, we have characterized both at the molecular and phenotypic level FBti0019386, a previously identified candidate adaptive TE. We first elucidated the evolutionary history of this natural insertion and provided evidences of genomic signatures of positive selection. We then explored several phenotypes related to known phenotypic effects of nearby genes, and having plausible connections to fitness variation in nature. We found that flies with FBti0019386 insertion had a shorter developmental time and were more sensitive to stress, which are likely to be the adaptive effect and the cost of selection of this mutation, respectively. Interestingly, these phenotypic effects are not consistent with a role of FBti0019386 in temperate adaptation as has been previously suggested. Indeed, a global analysis of the population frequency of FBti0019386 showed that climatic variables explain well the FBti0019386 frequency patterns only in Australia. These results suggest that further functional validation should be gathered before concluding that a candidate loci is under spatially varying selection. Finally, although FBti0019386 insertion could be inducing the formation of heterochromatin by recruiting HP1a (Heterochromatin Protein 1a) protein, the insertion is associated with up-regulation of sra in adult females. In the second chapter of this thesis, we have studied the impact of several TE insertions in a highly conserved and ecologically relevant trait: the immune response. To do that, we first performed a new genome-wide screening in order to identify a dataset of candidate TEs involved in adaptation. By increasing the number of populations and the number of TEs analyzed compared to similar studies, we were able to increase the number of identified candidate TEs: a total of 121 TEs. Interestingly, we found that genes associated with those TEs are enriched for stress-related functions, specifically we detected a significant enrichment for immune response functions. We combined allele-specific expression (ASE), enhancer assays, and TSS detection experiments to characterize the impact of these TEs in oral immune response to the gram-negative bacteria Pseudomonas entomophila. We were also able to associate the 12 candidate TEs with gene expression changes, and determine some of the molecular mechanisms behind these expression changes. We showed that the allele with the TE was differently expressed in 13 out of the 16 analyzed genes under non-infected and/or infected conditions in at least one of the two genetic backgrounds analyzed. We also show that different TEs alter gene expression by adding promoters and enhancer regulatory sequences to their nearby genes. Although we found evidences pointing to a possible role of TEs in immune response regulation, more experiments should be performed in order to link the identified TEs with a fitness effect in this trait. Overall, our two integrative approaches allowed us to shed light on the role of TEs in generating genomic natural variation potentially underlying adaptation. The results obtained in this work illustrate that TEs are a good tool to bridge the gap between genotypic and phenotypic evolution. Un dels reptes actuals en biologia és explicar la base genètica de l’adaptació. Mentre que hi ha molts estudis basats en SNPs intentant trobar les bases genètiques de les relacions genotip-fenotip, no s’ha estudiat tant bé el paper de les mutacions generades pels elements mòbils (TEs, de l’anglès Transposable Elements). Evidències recents demostren que els TEs són una eina potent per identificar les bases genètiques dels fenotips adaptatius. Drosophila melanogaster és un bon model per estudiar l’adaptació, ja que és originària de l’Àfrica subtropical i recentment ha colonitzat altres ambients. Per identificar i caracteritzar el paper de diversos TEs candidats per l’adaptació a D. melanogaster, hem seguit dues estratègies diferents: locus-específica i tret-específica. En el primer capítol hem caracteritzat a nivell molecular i fenotípic el TE FBti0019386, identificat prèviament com a candidat per l’adaptació. Primer hem estudiat la història evolutiva d’aquesta inserció i hem demostrat que està associada a senyals genòmiques de selecció positiva. Després hem explorat diferents fenotips relacionats amb els efectes fenotípics coneguts dels gens del costat, que poguessin tenir connexions plausibles amb la variació de la fitness a la natura. En el segon capítol, hem estudiat l’impacte de diferents TEs en la resposta immune. Per això, hem mostrejat el genoma buscant TEs candidats per l’adaptació en quatre poblacions naturals. Després, hem combinat anàlisis d’expressió específica d’al·lel, assajos d’enhancer i detecció de TSS per caracteritzar l’impacte d’aquests TEs durant la resposta a infecció amb el bacteri gram-negatiu Pseudomonas entomophila. Hem trobat que l’al·lel amb el TE s’expressa de manera diferent en 13 dels 16 gens analitzats en condicions control i/o d’infecció en almenys un dels dos fons genètics analitzats. Hem demostrat que alguns d’aquests TEs alteren l’expressió afegint promotors i enhancers als gens del costat. Tot i que les evidències assenyalen cap a un possible paper dels TEs en la regulació de la resposta immune, es requereixen més experiments per associar els TEs identificats amb un efecte en la fitness. En resum, les dues estratègies integratives seguides ens han permès mostrar el paper dels TEs en la generació de variació natural genòmica potencialment implicada en l’adaptació.

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Alasoo, Kaur. "Regulation of gene expression in macrophage immune response." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/263855.

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Gene expression quantitative trait loci (eQTL) mapping studies can provide mechanistic insights into the functions of disease-associated variants. However, many eQTLs are cell type and context specific. This is particularly relevant for immune cells, whose cellular function and behaviour can be substantially altered by external cues. Furthermore, understanding mechanisms behind eQTLs is hindered by the difficulty of identifying causal variants. We differentiated macrophages from induced pluripotent stem cells from 86 unrelated, healthy individuals derived as part of the Human Induced Pluripotent Stem Cells Initiative. We generated RNA-seq data from these cells in four experimental conditions: naïve, interferon- gamma (IFNɣ) treatment (18h), Salmonella infection (5h), and IFNγ treatment followed by Salmonella infection. We also measured chromatin accessibility with ATAC-seq in 31-42 individuals in the same four conditions. We detected gene expression QTLs (eQTLs) for 4326 genes, over 900 of which were condition-specific. We also detected a similar number of transcript ratio QTLs (trQTLs) that influenced mRNA processing and alternative splicing. Macrophage eQTLs and trQTLs were enriched for variants associated with Alzheimer’s disease, multiple autoimmune disorders and lipid traits. We also detected chromatin accessibility QTLs (caQTLs) for 14,602 accessible regions, including hundreds of long-range interactions. Joint analysis of eQTLs with caQTLs allowed us to greatly reduce the set of credible causal variants, often pinpointing to a single most likely variant. We found that caQTLs were less condition- specific than eQTLs and ~50% of the stimulation-specific eQTLs manifested on the chromatin level already in the naive cells. These observations might help to explain the discrepancy between strong enrichment of diseases associations in regulatory elements but only modest overlap with current eQTL studies, suggesting that many regulatory elements are in a ‘primed’ state waiting for an appropriate environmental signal before regulating gene expression.

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Carriero, Mateus Maldonado. "Caracterização e análise de expressão dos genes das enzimas Arginase 1, Arginase 2 e Óxido Nítrico Sintase Induzível (iNOS) de Piaractus mesopotamicus em resposta à infecção por Aeromonas dhakensis." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/7901.

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Submitted by Luciana Sebin (lusebin@ufscar.br) on 2016-10-13T12:06:00Z No. of bitstreams: 1 TeseMMC.pdf: 4981123 bytes, checksum: d5a8170e8917fcba950766e44afd3868 (MD5) Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-14T20:37:51Z (GMT) No. of bitstreams: 1 TeseMMC.pdf: 4981123 bytes, checksum: d5a8170e8917fcba950766e44afd3868 (MD5) Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2016-10-14T20:38:06Z (GMT) No. of bitstreams: 1 TeseMMC.pdf: 4981123 bytes, checksum: d5a8170e8917fcba950766e44afd3868 (MD5) Made available in DSpace on 2016-10-17T12:54:16Z (GMT). No. of bitstreams: 1 TeseMMC.pdf: 4981123 bytes, checksum: d5a8170e8917fcba950766e44afd3868 (MD5) Previous issue date: 2016-02-25 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The main goal of the present work was to perform an expression analysis of the Arg1, Arg2 and iNOS genes in the liver, anterior kidney and spleen of pacu (Piaractus mesopotamicus) in 4 different times post-infection, in response to the experimental infection with the bacterium Aeromonas dhakensis. The strain used in the present study was isolated from a specimen of P. mesopotamicus from the CEPTA/ICMBio in Pirassununga – SP, characterized by biochemical tests using the VITEK 2 automated identification system, and identified as belonging to the genus Aeromonas. Further molecular analyses of the 16S rRNA, gyrB and rpoD genes showed that the isolated strain belonged to the species A. dhakensis, a species that had never been reported in South America. This strain was resistant to the antibiotics ampicillin, ampicillin/sulbactam, cefoxitin and meroponem, with a high virulence level against experimentally infected pacus, causing clinical signs of acute hemorrhagic septicemia. The fifty per cent lethal dose (LD50) was 1.1 × 105 CFU/fish. Once characterized, this A. dhakensis strain was used in the infection experiments in P. mesopotamicus in order to analyze the expression of the Arg1, Arg2 and iNOS genes. These genes were sequenced and, from the partial sequences, P. mesopotamicus specific primers were designed for the quantitative real time PCR (qPCR) expression analyses. Following the infection with A. dhakensis, the Arg1 gene expression levels decreased in the kidney 24 h post-infection; the Arg2 gene expression of reduced in the liver at 12 h and 24 h post-infection and increased in the spleen at 24 h and 48 h post-infection; the gene expression of iNOS was significantly increased in she spleen at 12 h, 24 h, and 48 h post-infection. The results of the present study showed that the Arg2 and iNOS genes were the most variable in response to the A. dhakensis infection, indicating that these are involved in the initial immune response to bacterial infections in P. mesopotamicus. The organ that was most involved in this response was the spleen, which showed the highest levels of variation in these genes after the challenge. This is the first study assessing the expression levels of the Arg1, Arg2 and iNOS genes in P. mesopotamicus following the infection with A. dhakensis, providing a valuable contribution for the understanding of the immune response mechanisms against bacterial pathogens in this important South American fish species. O presente trabalho teve como objetivo realizar uma análise da expressão dos genes das enzimas Arg1, Arg2 e iNOS no fígado, rim anterior e baço de pacu (Piaractus mesopotamicus) em 4 períodos diferentes pós-infecção, em resposta à infecção experimental pela bactéria Aeromonas dhakensis. A cepa bacteriana utilizada no presente estudo foi isolada de um exemplar de P. mesopotamicus obtido do CEPTA/ICMbio em Pirassununga – SP, caracterizada por testes bioquímicos pelo sistema de identificação automatizado VITEK 2 e identificada como sendo do gênero Aeromonas. Posteriores análises moleculares dos genes 16S rRNA, gyrB e rpoD demonstraram que a bactéria isolada era da espécie A. dhakensis, cuja ocorrência na América do Sul nunca havia sido relatada. Essa cepa se mostrou resistente aos antibióticos ampicilina, ampicilina/sulbactam, cefoxitina e meropenem, com elevado nível de virulência para pacus experimentalmente infectados, causando sinais clínicos de septicemia hemorrágica aguda. A dose letal para 50% dos animais infectados (DL50) foi de 1,1 × 105 UFC/peixe. Uma vez caracterizada, essa cepa de A. dhakensis foi utilizada no experimento de infecção em P. mesopotamicus para análise de expressão dos genes Arg1, Arg2 e iNOS. Esses genes foram sequenciados e, a partir das sequências parciais, primers específicos para P. mesopotamicus foram desenhados para as análises de expressão por PCR em tempo real quantitativo (qPCR). O gene Arg1 apresentou os maiores níveis de expressão basal no fígado, já o gene Arg2 foi mais expresso no rim e o gene iNOS apresentou os maiores níveis de expressão basal no rim e no fígado. Após a infecção por A. dhakensis, o gene Arg1 apresentou uma leve diminuição na expressão no rim no período de 24 h pósinfecção; o gene Arg2 apresentou uma redução na sua expressão no fígado nos períodos de 12 h e 24 h pós-infecção e um aumento na expressão no baço nos períodos de 24h e 48 h pósinfecção; e o gene iNOS apresentou aumento significativo nos níveis de expressão no baço nos períodos de 12 h, 24 h e 48 h pós-infecção. Os resultados do presente trabalho mostram que os genes Arg2 e iNOS foram os que apresentaram maior variação em resposta à infecção por A. dhakensis, indicando que estes genes estão envolvidos na resposta inicial à infecções por essa bactéria em P. mesopotamicus. O baço foi o órgão mais envolvido nessa resposta, apresentando os maiores variações nos níveis de expressão desses genes após o desafio. Este é o primeiro estudo avaliando os níveis de expressão dos genes Arg1, Arg2 e iNOS em P. mesopotamicus após infecção por A. dhakensis, fornecendo uma valiosa contribuição para o entendimento dos mecanismos de resposta imunológica contra patógenos desse importante peixe sul-americano.

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Redwood, Alec J. "Cytokine gene expression patterns and immune responses to systemic Candida albicans infection in inbred mice." Thesis, Curtin University, 1997. http://hdl.handle.net/20.500.11937/1182.

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Aims of the research:To characterise the tissue histology and tissue distribution patterns of C. albicans during systemic murine candidiasis.To develop a reliable, reproducible and sensitive SQ-RT-PCR for the quantitation of in vivo cytokine gene transcription.To use this technique to determine the in vivo pattern of tissue specific cytokine gene expression during systemic candidiasis.To determine if cytokine gene expression patterns vary between resistant BALB/c and sensitive CBA/CaH mice during primary systemic candidiasis.To determine if differences in tissue distribution of C. albicans in infected mice is matched by differences in tissue responses to infection.To determine if cytokine mRNA expression patterns during secondary systemic candidiasis, are different to those during primary systemic candidiasis.To determine if cytokine gene expression patterns vary between resistant BALB/c and sensitive CBA/CaH mice during secondary systemic candidiasis.

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Jones, Rebecca L. "Immune responses in hepatocellular carcinoma : potential for immunotherapy." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269217.

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Cooper, Laken N. "Effects of Sleep Fragmentation on the Immune System of Zebra Finches Using Cytokine Gene Expression." TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1623.

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Sleep loss is known to trigger an inflammatory response and increase serum corticosterone in both human and murine models. However, very little evidence is available on the potential effects of sleep loss in avian models. This study aims to construct a profile using cytokine gene expression data to determine how birds respond to sleep loss in a controlled environment. I investigated changes in pro-inflammatory (IL-1β and IL-6) and anti-inflammatory (IL-10) cytokine gene expression in the periphery (fat, liver, spleen, and heart) and brain (hypothalamus, hippocampus, and apical hyperpallium) in zebra finches exposed to a novel sleep fragmentation method. Serum corticosterone, body mass, and behavioral profiles also were assessed. Sleep was interrupted periodically for over 12 hours using a sleep fragmentation chamber, which was modified from those typically used in murine studies. This chamber contained a sweeping wire bar that moved the distance of the cage at 2-minute intervals. I predicted that sleep fragmented birds would exhibit elevated pro-inflammatory and reduced anti-inflammatory gene expression relative to those birds that were not sleep fragmented. In addition, I predicted a decrease in body mass and an increase in serum corticosterone levels because of sleep fragmentation. Contrary to my predictions, sleep fragmentation resulted in lower levels of IL-1β in the apical hyperpallium, but lower levels of IL- 10 in the hippocampus. No differences were detected in the adipose tissue of individuals exposed to sleep loss. Sleep fragmentation resulted in an increase in percent body mass lost. Serum corticosterone levels did not differ across groups. These data provide preliminary insight into the inflammatory response that is seen as a result of sleep loss in an avian model. Overall, it appears that as compared to some mammals such as murine rodents, birds are not as susceptible to sleep loss.

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Redwood, Alec J. "Cytokine gene expression patterns and immune responses to systemic Candida albicans infection in inbred mice." Curtin University of Technology, School of Biomedical Sciences, 1997. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=10970.

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Aims of the research:To characterise the tissue histology and tissue distribution patterns of C. albicans during systemic murine candidiasis.To develop a reliable, reproducible and sensitive SQ-RT-PCR for the quantitation of in vivo cytokine gene transcription.To use this technique to determine the in vivo pattern of tissue specific cytokine gene expression during systemic candidiasis.To determine if cytokine gene expression patterns vary between resistant BALB/c and sensitive CBA/CaH mice during primary systemic candidiasis.To determine if differences in tissue distribution of C. albicans in infected mice is matched by differences in tissue responses to infection.To determine if cytokine mRNA expression patterns during secondary systemic candidiasis, are different to those during primary systemic candidiasis.To determine if cytokine gene expression patterns vary between resistant BALB/c and sensitive CBA/CaH mice during secondary systemic candidiasis.

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Mehta, Ninad T. "Early Epigenetic Regulation of the Adaptive Immune Response Gene CIITA." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/biology_theses/24.

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The precise regulation of Major Histocompatibility class II (MHC-II) genes plays an important role in the control of the adaptive immune response. MHC-II genes are expressed constitutively in only a few cell types, but their expression can be induced by the inflammatory response cytokine interferon gamma (INF-γ). The regulation of MHC-II is controlled by a Master Regulator, the class II transactivator (CIITA). Multiple studies have shown that CIITA regulated expression of MHC-II is controlled and induced by INF-γ. It has been also shown that a functional CIITA gene is necessary for the expression of MHC-II genes. CIITA is thus a general regulator of both constitutive and inducible MHC-II expression. Although much is known about the transcription factors necessary for CIITA expression, there is little information as to the epigenetic modifications and the requisite enzymes needed to provide these transcription factors access to DNA. Previous studies in the Greer lab have shown that increased levels of acetylation of histones H3 upon INF-γ stimulation, as does tri-methylation of H3K4 upon prolonged cytokine stimulation. Similar observations were made at early time points post IFN-γ stimulation, where there is an instantaneous increase in the levels of H3K18ac and H3K4me3. In contrast to this, the levels of silencing modifications begin to drop with in the first 20 minutes of IFN-γ stimulation. The binding of STAT1 reaches its peak at about 60 minutes and the first transcripts for the protein start to appear as early as 40 minutes post the cytokines stimulation. Our study is the first to link the rapidly occurring epigenetic changes at the CIITA promoter pIV to EZH2

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Romero, Claudia. "CELLULAR IMMUNE RESPONSE AND GENE EXPRESSION PROFILING IN CROHN'S DISE." Doctoral diss., University of Central Florida, 2004. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2704.

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Despite the chronic debate in the etiology of crohn's disease (cd), a debilitating inflammatory bowel disease (ibd) closely related to ulcerative colitis (uc), an emerging interest in a possible mycobacterial role has been marked. Granuloma and pathologic manifestations in cd resemble aspects found in tuberculosis, leprosy and paratuberculosis. The latter, a chronic enteritis in cattle, goat, sheep and primates, which is similar to human enteritis, also known as cd, is caused by a fastidious, slow growing mycobacterium avium subspecies paratuberculosis (map). Due to the similarities between cd and paratuberculosis, a mycobacterial cause in cd has been proposed. Recent discovery of a possible association between nod2/card15 mutations and risk of cd added support to microorganism-host interactions. In this study, a possible mycobacterial role in cd etiology has been evaluated by investigating the presence of map dna, the state of the cellular immune response and microarray gene expression profiling in peripheral blood and surgical tissue from cd, uc and healthy control subjects. Nested pcr detected map dna in tissue from 10/12(83%) cd patients compared to 1/6(17%) non-ibd subjects. Fluorescence in situ hybridization (fish) with the aid of confocal scanning laser microscopy (cslm) detected map dna in 8/12(67%) cd subjects compared to 0/6(0%) in non-ibd subjects. The detection of map dna by either technique in tissue from cd subjects is significant compared to non-ibd subjects (p < 0.05). Map dna was also detected in both inflamed and non-inflamed tissue from patients with cd suggesting map infiltration in human tissue. Correlation of possible map presence and the function of polymorphonuclear leukocytes (pmn) and peripheral blood mononuclear cells (pbmc) in 19 cd patients and 12 controls have been evaluated. Pmn phagocytosis of viable fitc-map was suppressed in 13/19(68%) cd patients compared to 0/12(0%) in healthy controls (p<0.05). Pbmc phagocytosis of viable fitc-map was suppressed in 5/19(26%) of cd patients compared to 0/12(0%) of healthy controls (p<0.05). The proliferative response of pbmc with t-cell majority from cd and controls subjects was evaluated against pha, candida albicans, pwm and map ppd. Dysfunctional proliferative response against pha was found in 8/19(42%) cd patients compared to 1/12(8.3%) in controls suggesting possible t-cell anergy. Pbmc from 11 cd subjects reacted normally to pha, 7/11(64%) reacted strongly to map ppd suggesting previous exposure to mycobacteria, and 3/11(27%) did not react with map ppd suggesting lack of pre-exposure to mycobacteria. From the seven mycobacterial pre-exposed samples, 6/7(86%) showed a normal ability to recall antigens by activated macrophages when exposed to c. Albicans, and all 7 samples had a normal pwm response. Finally, microarray-chip technology was employed to identify the expression profile of genes that have a role in the immune response of cd patients. Rna was isolated from fresh buffy coats from 8 healthy controls, 2 cd, and 1 uc patients. Chips with an estimated of 30,000 human genes were hybridized to cdna from these samples. We found that 17% of the total number of genes was differentially expressed. Over 200 genes were involved in the immune response, 7 genes where common to both forms of ibd (uc and cd), and 8 genes were found to be either downregulated in cd and upregulated in uc or viceversa. The ifngr1 gene, which encodes the ligand-binding chain of the ifn-gamma receptor, was found to be downregulated in 2/2(100%) of cd patients, but not in uc patients. It is known that defects in ifngr1 are a cause of atypical mycobacterial infection and bcg infection. Patients suffering from this deficiency have an immunologic defect predisposing them to infection with mycobacteria. This correlates with the proposed theory as map being the causative agent of cd. Furthermore, the results indicate a host susceptibility requirement for the establishment of mycobacterial infection in cd patients. Further characterization of ifngr1 using real-time pcr is underway. Collectively, detection of map dna in the majority of cd tissue and the alteration in pmn and pbmc to respond efficiently to map may be related to the fact that mycobacterial pathogens infect phagocytic cells of susceptible hosts and consequently the immune response is dysregulated. Furthermore, the fact that a gene linked to mycobacterial susceptibility was found to be downregulated in cd patients only, strengthens the mycobacterial etiology of cd. In general, the data suggest a possible role for a bacterial pathogen in cd pathogenesis. Ph.D. Other Burnett College of Biomedical Sciences Biomolecular Sciences: Ph.D.

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Rabquer, Brqadley James. "The Immune Response to Streptococcus pneumoniae and Pneumococcal Polysaccharides." University of Toledo Health Science Campus / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=mco1157731794.

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43

Engstrand, Mats. "Cellular Immune Responses to Allografts and Cytomegalovirus." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3441.

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Maripuu, Linda. "Superantigens in group A streptococcus : gene diversity and humoral immune response." Doctoral thesis, Umeå universitet, Biomedicinsk laboratorievetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-46454.

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Group A streptococcus (GAS) is a strictly human pathogen that causes infections ranging from asymptomatic carriage to the highly lethal streptococcal toxic shock syndrome (STSS). GAS are classified according to the sequence of the variable 5’ end of the emm-gene that encodes the surface associated M-protein. In the late 1980s, outbreaks of GAS infections with high rates of STSS were reported in several parts of the world, including Sweden. Superantigens (SAgs), a group of exotoxins, have been described as key mediators of STSS due to their capacity to polyclonally activate T-cells and induce a massive release of inflammatory cytokines. Previous reports have revealed that sera from STSS patients have lower capacity to neutralize this SAg-mediated immune stimulation and a higher prevalence of GAS isolates with specific emm-genotypes during disease outbreaks. The aims of this thesis were to analyse the protective antibody response mounted by the host against SAgs produced by the infecting GAS isolate and to characterise the isolates emm-genotypes and SAg gene profiles. The clinical material examined was collected from patients with STSS, sepsis, erysipelas, or tonsillitis in Sweden between 1986 and 2001. Both acute- and convalescence-phase sera were analyzed, along with the infecting GAS isolates. The 92 clinical GAS isolates examined were found to exhibit a high degree of genetic diversity in terms of the number and identity of their SAg genes. Isolates with a given emm-genotype could be divided into subgroups on the basis of their SAg gene profiles. Ten different SAg gene profiles were identified in the 45 emm1 isolates examined; one of these ten was highly persistent, being observed in 22 isolates collected over 14 years. Two of the 11 known SAg genes in GAS, smeZ-1 and speA, were more prevalent in the emm1 associated profiles than in the SAg gene profiles of isolates with other emm-genotypes. Patients infected by GAS with the emm1-genotype were less likely to produce acute-phase sera that could effectively neutralize the T-cell mitogenicity induced by the infecting isolate’s extracellular products (EP). Sepsis patients whose sera exhibited this lack of neutralizing ability were more prone to developing STSS. Most patients whose acute-phase sera did not effectively neutralize the EP from the infecting isolate lacked protective antibodies in their convalescent-phase sera despite having elevated ELISA titers. The results reported herein show that combining SAg gene profiling with emm-genotyping may be useful for tracking the spread of GAS clones in the community. It was also shown that a lack of neutralizing activity in convalescence-phase sera might be due to an inability of those patients to mount a protective immune response against SAgs produced by the infecting GAS isolate.

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Williams, Kevin Jason. "NF- kB c-Rel dependent gene induction in the immune response." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1779835231&sid=6&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Pearce, Oliver M. T. "Controlled virus glycosylation : engineering adenoviruses as targetable stealth vectors for gene therapy." Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670156.

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Ferrer, Roig Aurora. "Immune responses to dystrophin : implications for gene therapy of DMD." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395118.

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Urrutia, Alejandra. "Defining the boundaries of a healthy immune response using standardized immune monitoring tools." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066004/document.

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Le projet Milieu Intérieur a pour but d'identifier les facteurs génétiques et environnementaux ayant un impact sur la variabilité immunitaire naturelle. Cette analyse multiparamétrique requière néanmoins d'utiliser des outils standardisés. Afin d'étudier la réponse immune induite, nous avons utilisé un système optimisé prêt à l'emploi de stimulation du sang et développé un protocole unique de quantification de l'ARN afin d'étudier la signature transcriptionnelle en réponse à des immuno-modulateurs. Testant l'hypothèse que la réponse à des composés complexes peut être définie par la signature ARN de cytokines clefs et utilisant une méthode statistique robuste, nous avons identifié 44 gènes capables d'optimiser la capture de la réponse à des stimulations plus complexes aidant à la réduction dimensionnelle pour la décomposition de réponses innées. Dans une seconde étude, l'analyse semi-automatisée par cytomètrie en flux des cellules du sang a été associée à l'analyse épidémiologique et génotypique pour les 1,000 donneurs inclus dans la cohorte. Nous avons observé que le tabac, l'âge, le genre et l'infection latente par le cytomégalovirus sont les facteurs impactant le plus la variabilité immunitaire. Cette étude a montré que les paramètres des cellules innées sont contrôlés par des facteurs génétiques alors que ceux des cellules adaptatives le sont plutôt par des expositions environnementales tout au long de la vie. Des outils interactifs incluant ces données de référence accompagnent ces études. Ces analyses montrent que nous avons développé des outils performants pour une étude intégrative du modèle humain constituant une approche innovante vers une médecine personnalisée The project Milieu Intérieur aims to study the genetic and environmental factors that can have a major impact on occurring immunological variance in healthy human population. This characterization requires the use of standardized immunophenotyping technologies for integrating diverse, complex datasets. With this goal in mind, we used an optimized suite of standardized whole-blood stimulation systems to study the human induced immune response in physiological condition and developed a unique standardized protocol to analyze the ARN signatures upon whole-blood stimulation to test the hypothesis that responses to complex stimuli can be defined by the transcriptional signatures of key cytokines. We found 44 genes, identified using Support Vector Machine learning, which captured the diversity of complex innate immune responses with improved segregation between distinct stimuli. This provides new strategies for dimension reduction of large datasets and for deconvolution of innate immune responses, applicable for characterizing novel immunomodulatory molecules.In a second related study, we aimed to identify the environmental and genetic factors driving innate and adaptive immune cell parameters in homeostatic conditions. To do so, we combined semi-automated flow cytometric analysis of blood leukocytes and genome-wide DNA genotyping in the 1,000 healthy donors included in the collection. We show that smoking, age, gender and latent cytomegalovirus infection, are main drivers of human variation (i.e. numbers of Treg and MAIT cells). These results demonstrated that innate cell parameters are strongly controlled by genetic factors, whereas adaptive cells are driven by life-long environmental exposures. In addition, to help on the public data mining, we developed interactive R-Shiny application including healthy donor reference values for both studies.All together, these results indicate that we developed powerful tools for human system biology approaches to support personalized medecine

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Reichel, Felix Friedrich Lambert [Verfasser]. "Immune response to ocular gene therapy with AAV8 / Felix Friedrich Lambert Reichel." Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1222510952/34.

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Sun, Huaichang. "Characterisation of immune responses to African swine fever virus-encoded antigens." Thesis, University of Hertfordshire, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260800.

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Dissertations / Theses on the topic 'Immune response genes'

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