Dissertations / Theses: 'Antigen antibody reaction'

1

Andersson, Kerstin. "Antigen-antibody reactions a study of functional structures and non-immunological interactions /." Lund : Dept. of Biochemistry, Lund University, 1995. http://catalog.hathitrust.org/api/volumes/oclc/39264530.html.

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Schuman, Jason Tyler. "Structural and dynamical investigations of the interaction between the MUC1 tumor antigen and the humoral immune system : towards the design of a second generation cancer vaccine /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/8613.

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Thornton, Gail Marilyn. "Biolithography : selective joining using antibody-antigen reactions." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/42816.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1995.
Includes bibliographical references (p. 211-212).
Biolithography is a contribution to the field of Solid Free Form Fabrication. Part production is based on selective joining using antibody- antigen reactions, where the selectively is based on the thermal sensitivity of such proteins. Antibodies and antigens can be chemically immobilized to a variety of substrate materials: polymeric, ceramic and metallic. In the present investigation, antibody coated 1 [mu]m polystyrene beads and antigen coated glass surface substrates, as well as, antigen solutions were used. Both antibodies and antigens were multivalent i.e. have more that one binding site for each other; thus, two antibody coated beads could be held together by one antigen. Selective deposition was demonstrated by thermally deactivating antigen coated onto glass and precipitating antibody coated beads. Bead deposition was selective to the regions of remaining active antigens; thus, revealing the defined deactivated region. Thermal deactivation of the antigen coated substrate was first demonstrated with a 90°C water jet and improved using an argon ion laser which produced line widths on the order of tens of microns. Selective definition of geometry was an extension of the coating process precipitating not one but two bead layers and linking beads using antigen in solution. The thermal deactivation mechanism was a modified 90°C water jet that had line width resolution on the order of millimeters. Line definition was on both antigen coated bases and bound bead bases; thus, thermal deactivation was effective on both immobilized antigen (glass) and antibody (bead). The selective deposition of antibody coated substrate was demonstrated by thermally deactivating immobilized antigens and antibodies on surface substrates. Definition resolution was dependent on the thermal deactivation mechanism used.
by Gail Marilyn Thornton.
S.M.

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Tsui, Ka-kit, and 徐家傑. "Seasonal variation of serum prostate-specific antigen levels in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40738292.

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Tsui, Ka-kit. "Seasonal variation of serum prostate-specific antigen levels in Hong Kong." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40738292.

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6

Otali, Dennis. "The combined effect of formalin fixation and individual steps in tissue processing on immunorecognition." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2008r/otali.pdf.

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7

Gonzalez, Elfwing Olivia, and Elin Nilsson. "Utvärdering av icke-invasiva metoder för diagnostik av Helicobacter pylori-infektion : En systematisk litteraturstudie." Thesis, Hälsohögskolan, Jönköping University, HHJ, Avd. för naturvetenskap och biomedicin, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-48758.

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Helicobacter pylori-infektion är en av de ledande orsakerna till utvecklingen av maligniteter i ventrikeln. Tillämpning av pålitliga analytiska metoder är därför väsentlig för en korrekt diagnostik och behandling av infektionen. Syftet med studien var att ge en översikt av icke-invasiva metoder som tillämpas för påvisning av H. pylori och utvärdera vilken metod som är bäst lämpad, med avseende på metodens prestandaegenskaper och det kliniska tillståndet hos patienten. En systematisk litteraturöversikt utfördes, genom sökning efter vetenskapliga artiklar med inklusions- och exklusionskriterier i databaserna PubMed och CINAHL. Utvalda artiklar kvalitetsgranskades och 20 studier inkluderades i resultatet. Sammanställt hade fecesantigentester en sensitivitet och specificitet på 92,64% respektive 91,47%, antikroppstester hade 97,20% respektive 81,59%, urea utandningstester hade 91,40% respektive 91,70% och polymeraskedjereaktionen hade 75,45% respektive 98,30%. Därutöver hade kliniska tillstånd såsom atrofisk gastrit, intestinal metaplasi och gastrointestinal blödning en negativ påverkan på metodernas diagnostiska tillförlitlighet. Studien konstaterade att beträffande metodens prestanda är fecesantigentester mest lämpliga för påvisning av H. pylori- infektion. Vid allvarligare kliniska åkommor bör minst två icke-invasiva diagnostiska metoder tillämpas för att säkerställa pålitliga resultat.
Helicobacter pylori infection is one of the leading causes of ventricular pathologies. Reliable analytic methods are therefore crucial for the correct diagnosis and treatment of the infection. The aim of this study was to provide an overview of non-invasive diagnostic methods used for the detection of H. pylori and to evaluate which method is most suitable, considering its performance and the clinical condition of the patient. A systematic literature review was conducted, searching peer-reviewed research articles with inclusion and exclusion criteria on the databases PubMed and CINAHL. An assessment of the selected articles quality resulted in the inclusion of 20 articles. Overall, stool antigen tests had a sensitivity and specificity of 92,64% and 91,47% respectively, antibody tests 97,20% and 81,59% respectively, urea breath tests 91,40% and 91,70% respectively, and the polymerase chain reaction 75,45% and 98,30% respectively. Furthermore, conditions such as atrophic gastritis, intestinal metaplasia and gastrointestinal bleeding had a negative impact on the diagnostic accuracy of the methods. This study concluded that, regarding the methods performance, stool antigen tests are more suitable for detecting a H. pylori infection. With the mentioned clinical conditions, at least two non- invasive diagnostic methods should be used to ensure reliable results.

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De, Leon Ellen Jane Biotechnology &amp Biomolecular Sciences Faculty of Science UNSW. "Engineering antibodies against complex platelet antigens using phage display technology." Awarded by:University of New South Wales, 2007. http://handle.unsw.edu.au/1959.4/37009.

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Platelets are small anucleate cell fragments found in blood whose physiological role is important in maintaining haemostasis. In vivo, platelet surface glycoproteins mediate the mechanistic roles of platelets, and polymorphic changes to these glycoproteins have been observed to have significant effects on the platelet cellular function and such changes may include over-expression, under-expression and antigenicity of the protein. Human platelet antigens (HPA) are a result of polymorphic differences in platelet surface glycoproteins which have been found to be variably expressed in the population. Foetal maternal alloimmune thrombocytopaenia (FMAIT) is a condition that is observed in the unborn foetus and neonates due to HPA incompatibility between the mother and the foetus. HPA incompatibility accounts for a majority of severe thrombocytopaenic cases in neonates, and delayed diagnosis and treatment of such a condition often lead to intracranial haemorrhage. The risk in neonates diagnosed with FMAIT becomes increasingly significant in cases where intra-uterine (during pregnancy) platelet transfusion is the only effective therapeutic option. There are currently no antenatal screening programs for this condition, and laboratory diagnosis of FMAIT relies on the detection of maternal alloantibodies and parental HPA typing. For these reasons a significant amount of research is currently being invested into the isolation of recombinant antibodies with specific reactivity against FMAIT-related platelet antigens. Stable and specific recombinant platelet antibodies have great potential as a diagnostic agent in antenatal screening and broad-scale HPA typing of blood donors for platelet transfusion. Further characterisation of the isolated antibody may lead to a possible therapeutic agent. Studies by previous researchers have shown that the traditional methods (ie. Mouse monoclonal and EBV transformation) of obtaining monoclonal antibodies against FMAIT-related antigens have proven unsuccessful. The continuing progress in the discipline of phage display has produced several novel antibodies against self and non-self antigens. A further advantage in the application of phage display technology for the isolation of novel antibodies is the easy transition from bacterial to mammalian expression for the characterisation of glycosylated antibodies. The main focus of this project was to create and isolate a recombinant human anti-HPA-3a antibody using phage display for its possible application as a therapeutic or diagnostic agent.

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Mummert, Mark E. "Stability in antigenic reactivity of the major outer surface protein, OspA, in borrelia burgdorferi, during persistent infection in Syrian hamsters." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/845968.

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The spirochete Borrelia burgdorferi is the causative agent of Lyme disease, a multisystem disorder that can cause a variety of disorders in susceptible mammalian hosts. The immune response of infected mammals, including humans, is ineffective in clearing B. burgdorferi as demonstrated by the ability to reisolate the spirochete from naturally and experimentally infected hosts after extended periods of time. Recent evidence suggests that this pathogen evades the immune response in part through changes in antigenic reactivity.The purpose of this study was to determine if outer surface protein A (OspA) of B. burqdorferi varies in the course of infection in Syrian hamsters and thus potentially plays a role in evading the host immune response. To assess the degree of change, differences in the binding of a murine monoclonal antibody (H5332) were measured using IFA and ELISA techniques over a 9-week period of time.Results of this study suggest that OspA is persistently expressed in infected Syrian hamsters for at least 9-weeks. Moreover, this protein, or at least the epitope that H5332 binds with, is stably expressed. These results indicate OspA, or at least the epitope of OspA that I probed, does not appear to contribute to the evasive mechanisms of 8. burgdorferi in Syrian hamsters.
Department of Biology

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Luo, Cheng-Ping. "Detection of antibody antigen reactions using surface acoustic wave and electrochemical immunosensors." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971863121.

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Barbar, Elisar Jamil. "Nuclear Magnetic Resonance Study of Antigen-Antibody Complexes, Including Sequence Specific Assignments and Structural Analysis of Neurophysin as an Antigen Model." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/1167.

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The interaction between molecules is essential in a wide range of biological processes. A detailed knowledge of these interactions is necessary for understanding these processes. Among the systems that involve important interactions is the immune system. NMR spectroscopy has a large number of spectral parameters that were used in this work to study antibody-antigen interactions. These same parameters were also used to begin a structural analysis of a medium-sized protein, neurophysin, that has important interactions with neurohormones, and served here as a model antigen. A set of ligands differing in size and charge was designed and used to probe the binding site of anti-phosphocholine antibodies. These ligands ranged from small organic species to medium sized proteins. Amino acids, peptides and proteins were homogeneously linked to phenyl phosphocholine and analyzed by NMR techniques. Transferred nuclear Overhauser effect measurements were used to determine the conformation of bound ligands. The conformational change observed in some ligands was explained as either due to the antibody selecting one conformation that already exists, or the antibody binding inducing a conformational change. Titration data and detailed NMR analysis showed a more rigid M3C65 antibody fragment upon binding. In summary, with eight examples of ligands and four examples of antibodies studied by NMR, a spectrum of effects was seen, including a lock-and-key model and limited local induced fit. The contribution of the carrier molecule to antibody binding was in restricting the conformation of the ligand. Bigger ligands that are expected to be more immunogenic, showed less binding avidity as determined by immunological assays. Fluorinated ligands were synthesized to determine the kinetics of binding using 19F NMR spectra. Higher concentration of a fragment of the antibody M3C65 was analyzed to determine assignments of some residues in the combining site of the antibody. High resolution NMR techniques were used to assign resonances in neurophysin. The physiological role of neurophysin includes hormone storage and stabilization of oxytocin and vasopressin against proteolytic degradation within the posterior pituitary. Neurophysin is a 10 KD protein that dimerizes at high concentrations needed for NMR studies. An organic cosolvent was used to lower the dimerization constant, and hence inrease the spectral resolution. This permitted sequence-specific assignments that were then used to identify residues in the neurophysin-hormone binding site. Chemical shift differences and conformational changes were observed for the residues glutamate 47 and leucine 50. The 3₁₀ helix was further stabilized towards a more ideal helix upon hormone-analog peptide binding. Some of the residues contributing to the monomer-monomer interface were also assigned. Dimerization ill1duced chemical shift differences and conformational changes were observed for phenylalanine 35, threonine 38, and alanine 69. Tyrosine: 49 and phenylalanine 22 were affected but to a lesser extent. One characteristic of neurophysin in all studied cases was dynamic equilibrium between different folding states.

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12

Johansson, Daniel X. "Expression and interaction studies of recombinant human monoclonal antibodies /." Stockholm, 2007. http://diss.kib.ki.se/2007/978-91-7357-137-1/.

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13

陳磊碩 and Lui-sek Chan. "Chemical modification of immunoglobulins and the effects on antigen binding site affinity." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B29913378.

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Chan, Lui-sek. "Chemical modification of immunoglobulins and the effects on antigen binding site affinity /." [Hong Kong] : University of Hong Kong, 1993. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13731506.

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15

Jacob, Laurent. "Role immunogene d'une proteine de surface cellulaire au cours du lupus erythemateux dissemine." Paris 6, 1986. http://www.theses.fr/1986PA066541.

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Le lupus erythemateux dissemine est une maladie auto-immune caracterisee par la production d'anticorps antidna double brin qui sont un marqueur du lupus erythemateux dissemine et qui sont consideres comme etant responsable des lesions tissulaires du lupus par l'intermediaire du depot de complexes immuns dna anti-dna. Des anticorps anti dna monoclonaux specifiques du dna double brin ont ete produits dans des modeles experimentaux de souris lupiques b/w. Nous avons montre que ces anticorps anti-dna monoclonaux reconnaissent 5 polypeptides a la surface de differents types cellulaires concernes dans la pathogenie du lupus. Nous avons montre qu'il existe un motif antigenique commun entre le dna double brin et ces polypeptides membranaires. Nous avons isole ces polypeptides membranaires et produit un anticorps polyclonal contre ces polypeptides. Nous suggerons que ces polypeptides membranaires pourraient jouer le role d'immunogene que ne joue pas le dna double brin

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16

Liu, Ming-Sun. "Studies of a sperm acrosomal antigen recognized by HS-63 monoclonal antibody." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30996.

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A sperm specific and species conserved monoclonal antibody (HS-63) was shown to inhibit in vitro fertilization of mouse oocytes and human sperm penetration to zona-free hamster ova. The sperm antigen (SA-63) which reacts with HS-63 was found to be localized on the sperm acrosome. Following sperm capacitation, this antigen becomes exposed and is shed after the acrosome reaction. SA-63 may be involved in the sperm acrosome reaction during the initial fertilization process. Sperm antigen (SA-63) from mouse (MSA-63) was purified from mouse testes with soluble and detergent extraction procedures followed by immunoaffinity chromatography. The purified MSA-63 antigen was shown to be a group of proteins with a size ranging from 25 Kd to 50 Kd and pIs of about 4.2 when analyzed by two dimensional gel electrophoresis. MSA-63 antigen may be associated with actins in its native form. A proteolytic activity was found in the solution of purified MSA-63 preparation. Purified MSA-63 was used for immunization of mice and rabbits. Following successive immunizations, antisera of high titres were raised and reacted specifically with sperm acre-some. The isoimmune sera from immunized mice exhibited significant inhibition on in vitro fertilization of mouse oocytes. Complementary deoxyribonucleic acid (cDNA) fragments encoding the MSA-63 were cloned from a mouse testis cDNA library by using an immunoscreening method with rabbit antisera against MSA-63 as the detecting probe. When a specific cDNA probe was used for Northern blot analysis, an mRNA of 1.5 Kb in size was detected only in the adult mouse testis, but not in any other somatic tissues. By Southern blot analysis, it was also demonstrated that the gene encoding for SA-63 protein is conserved among different mammalian species. The location of SA-63 antigen gene was determined to be on human chromosome 11 when analyzed with a blot of a human-hamster somatic cell hybrid panel. By DNA sequence analysis, a protein of 28 Kd in size was deduced from the MSA-63 cDNA. The amino acid sequences of trypsin-digested peptide fragments of MSA-63 were used to verify that deduced amino acid sequence from the cDNA. The recombinant fusion proteins containing MSA-63 protein fragment were produced in E. coli and used to immunize female mice. Similar to the original HS-63 monoclonal antibody, the antisera thus produced reacted only with the sperm acrosome and revealed significant inhibition of the in vitro fertilization of mouse oocytes. In the developing mouse testis, the expression of MSA-63 gene was found to be post-meiotic. Protein and mRNA of MSA-63 were not produced until day 20 after birth.
Medicine, Faculty of
Obstetrics and Gynaecology, Department of
Graduate

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17

Goff, Randal D. "Structure-activity studies of glycosphingolipids as antigens of natural killer T cells /." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1519.pdf.

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18

Babakhani, Farah Kondori 1960. "IN VITRO PRODUCTION AND SPECIFICITY OF ANTI-DNA AUTO ANTIBODIES BY NEW ZEALAND BLACK/NEW ZEALAND WHITE F1 MICE." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/276471.

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Kwong, Pearl Chu. "Characterization of an antigen-specific T helper cell clone and its products." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27366.

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A T helper cell clone, referred to as clone 9, was derived from an allogeneic mixed lymphocyte culture. Clone 9, as well as supernatant factor(s) derived from it, could help the cytotoxic T lymphocyte (CTL) responses of H-2 Db (Db) responder cells to alloantigens, or they could help the CTL responses of non- Db responder cells to Db alloantigens. Clone 9 cells or their factor(s) were active only when added during the first 24 hours of a five-day culture period. Clone 9 or its factor(s) could also synergize with interleukin-2 (IL-2)-containing medium in mounting cytotoxic responses to alloantigens. The helper activity in clone 9 supernatant was not due to IL-2 and it was specifically absorbed out by Db -spleen cells. The characterization of the Db -specific helper factor(ASHF) was facilitated by the isolation of a T hybridoma clone (clone 25), obtained from fusion of clone 9 cells with the T cell lymphoma, BW5147, and a B cell hybridoma that produced an IgM monoclonal antibody (clone 30 IgM) which bound ASHF. An additional monoclonal antibody (F23.1), which recognizes a determinant of the Vβ8 family of the T cell receptor, was also particularly useful for the characterization of ASHF. Analysis with these reagents showed that both clone 30 IgM and F23.1 immunoadsorbents could retain ASHF activity. Preabsorption of the ASHF with Db spleen cells prior to affinity purification over a clone 30 IgM column resulted in the absorption of Db-specific helper activity as well as the loss of a 50,000 molecular weight (MW) band on SDS-PAGE under reducing conditions. Furthermore, affinity purification of ASHF over the F23.1 immunoadsorbent, but not an irrelevant monoclonal antibody (mAb) column, also yielded a 50,000 MW molecule. Taken together, these findings suggest that the 50,000 MW molecule is a component of the ASHF and it is intimately related to the B chain of the T-cell receptor. The mode of action of clone 9 and its products in the induction bfCTL responses was also investigated. It was found that clone 9 and ASHF could help CTL responses by inducing IL-2 production in B6-stimulated cultures. In addition to ASHF, clone 9 cells also produced an additional factor(s) which participated in the induction of CTL responses. This additional factor(s) was referred to as IL-X. IL-X synergized with excess human recombinant IL-2 in the activation of CTL precursors (CTL-P) in the absence of antigenic stimulation. A model which involves the participation of ASHF, T helper cells, IL-2 and IL-X in the induction of CTL responses is proposed.
Science, Faculty of
Microbiology and Immunology, Department of
Graduate

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20

Grinstead, Jeffrey Scott. "Structural immunology of humoral and cellular recognition of a MUC1 breast cancer antigen /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/8180.

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21

葉德俊 and Tak-chun Timothy Yip. "Characterization of a monoclonal antibody reactive against major histocompatibility complex class II antigens." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B3123334X.

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Yip, Tak-chun Timothy. "Characterization of a monoclonal antibody reactive against major histocompatibility complex class II antigens /." [Hong Kong] : University of Hong Kong, 1992. http://sunzi.lib.hku.hk/hkuto/record.jsp?B13478771.

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23

TANAKA, KENJI, SHIMPEI TORII, MICHIO HOMMA, and AYAKO ISHIGURO. "Identification of Candida albicans antigens reactive with immunoglobulin E antibody of human sera." Thesis, American Society for Microbiology, 1992. http://hdl.handle.net/2237/19576.

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24

Eichbaum, Quentin Gavin. "Antigenic mimicry and autoantibodies in rheumatic fever." Doctoral thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/26296.

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25

Green, Melanie Leslie Dawn. "The identification of novel autoantigens by means of serological screening of a cDNA expression library constructed from multiple sclerosis brain tissues." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0018/MQ54892.pdf.

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Fairlie-Clarke, Karen Jane. "Significance of cross-reactive antibody responses and isotype bias in malaria-helminth co-infection." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5727.

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The socio-economic and geographical distribution of malaria overlaps with that of many parasitic helminths and in these areas co-infections are common. Co-infection with helminths can influence disease outcome causing either exacerbation or amelioration of malaria. Understanding the complex host-parasite interactions that lead to these different disease outcomes is important for the success of control programmes aimed at these parasites. The immune system has evolved diverse types of response (e.g. T-helper 1 (Th1) and T-helper 2 (Th2)) to efficiently combat infection with ‘microparasites’ and helminths respectively. When faced with co-infection however, the need for the host to multitask means it must manage these counter-regulatory responses. In this study a murine model of malaria-hookworm (Plasmodium chabaudi- Nippostrongylus brasiliensis) co-infection was utilised to investigate how changes in T-helper bias affect malaria disease outcome. Antibody isotypes were used as indicators of Th1/Th2 bias and revealed that helminth co-infection reduced the malaria-specific Th1 response. Counter-intuitively this resulted in ‘protection’ from malaria with co-infected mice having reduced peak P. chabaudi parasitaemia and suffering less severe anaemia. In addition to providing a measure of Th1/Th2 bias, analysis of antibody responses revealed the occurrence of cross-reactive antibodies. The potential for these crossreactive antibodies to influence disease outcome was investigated but in this murine model resource-mediated mechanisms of parasite regulation appear to be responsible for the ‘protection’ that co-infection affords. The question of why cross-reactive antibodies are produced has important immunological and ecological implications. Cross-reactive responses may arise through some physiological constraint on the immune mechanisms that usually result in antibody-specificity. However experiments designed to investigate if the specificity of antibodies is constrained by availability of antigen suggest that this is not the case in the model system used here. There is also the possibility that production of cross-reactive antibodies represents an evolutionary optimal strategy for a host faced with unpredictable exposure to a variety of parasites. However a major finding of this study indicates these two taxonomically distinct parasite species share antigens, which in itself is crucial to understanding host-parasite interactions in a co-infection setting. The main findings of this thesis are relevant to co-infection studies in general and the implications for both evolutionary and applied biology are discussed.

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George, Dashwill Anton. "Validation and application of the ELISA technique for the detection of fish aero-antigens." Thesis, Peninsula Technikon, 2003. http://hdl.handle.net/20.500.11838/1484.

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Thesis (MTech (Biomedical Technology))--Peninsula Technikon, 2003
Increased seafood consumption due to its nutrition and promotion of a healthy diet has lead to more frequent reports of allergic reactions. In the seafood industry, workers are exposed to the antigens through inhalation of the vapours created during the seafood processing and cooking. Most seafood allergens are stable molecules, which are resistant to the effect of cooking and processing. The prevalence of occupational asthma varies from 7-36% among different groups of workers including seafood processing and fishmeal workers, fishermen and restaurant cooks (Jeebhay et al 2001). Purpose of Study: The purpose of the study is to determine total protein and the specific fish antigen concentrations in the environment by means of personal air sampling filters obtained from various categories of workers in the seafood processing industry. Objectives: • To determine the correlation between total protein concentrations and specific fish (pilchard and anchovy) antigen concentrations on personal air sampling filters using the linear response model of the standard curve. • To determine the correlation between total protein concentrations and specific fish (pilchard and anchovy) antigen concentrations on personal air sampling filters using the sigmoidal response model with a variable slope of the standard curve. • To identify the most efficient standard curve response model for fish antigen detection by comparing the percentage recovery of the linear standard curve response model and the sigmoidal standard curve response model. Methodology: A sample population of 195 samples was taken from workers in the seafood industry at the St. Helena Bay Fisheries and West Point Processors using personal air sampling pumps.

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Rogers, Todd H. "Receptor recognition and response of dendritic cells to biomaterials." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37107.

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The goal of the work presented was to further understand how both the body and dendritic cells (DCs) interact and respond to biomaterials through receptor-mediated mechanisms. The role of Toll-like receptor 4 (TLR4) was investigated in the host response to biomaterials, and it was found that TLR4-deficient mice (in comparison to wild-type) had a delayed acute inflammatory response as seen through an altered adherent leukocyte profile on implanted polymer discs. However, following a 2 week implantation, the response was resolved potentially through compensatory receptors. Therefore, TLR4 may aid in the initial response to a biomaterial through recognition of 'danger signal' molecules. An investigation into the role of TLR4 in the response of DCs to biomaterials was investigated using murine bone marrow-derived DCs (BMDC), and PLGA film or microparticle treatment of BMDCs resulted in TLR4-dependent signs of slight maturation in non/loosely adherent BMDCs. However, further investigation into BMDC populations within the culture system revealed that non/loosely adherent BMDCs took on an activated/mature phenotype while adherent BMDCs appeared to be less mature and more responsive to both LPS and biomaterial stimuli. Therefore, it was concluded that investigations into the responsiveness of BMDCs to stimuli in the future analyze both adherent and non/loosely adherent populations. Lastly, the role of integrin-mediated adhesion in biomaterial-induced DC maturation was investigated. Gene expression analysis revealed that PLGA treatment of human DCs increased adhesion molecule expression (including β1 and β2 integrin subunits), LPS treatment reduced adhesion molecule expression and agarose treatment did not alter their expression. Antibody blocking techniques pinpointed the role of β2 integrins (and not β1 integrins) in both the adhesion of DCs to TCPS or PLGA substrates and the regulation of a DC maturation marker (CD86). β2 (and not β1) was found co-localized with F-actin in podosomes of DCs adhering to PLGA, and the direct interaction of β2 (and not β1) to PLGA substrate was confirmed through crosslinking and immunofluorescence studies. Therefore, DCs utilized β2 integrins for both adhesion and maintenance of immunomodulatory status. This aids the field of tissue engineering and vaccine design by further developing the criteria for biomaterial-influenced immunomodulation.

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29

Altindis, Emrah. "Identification Of The New Immunogenic Proteins Of Bordetella Pertussis By Immunoproteomics." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608320/index.pdf.

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The genus Bordetella contains several pathogenic species generally associated with upper respiratory tract infections in warm-blooded animals. Bordetella pertussis is the etiologic agent of whooping cough. Whooping cough is presently one of the ten most common causes of death from infectious diseases and reported by the World Health Organisation (WHO) to cause 50 million cases and 350000 deaths worldwide per year, mainly among unvaccinated individuals in poor countries. The term proteome, in analogy to the term genome, was coined to describe the complete set of proteins that an organism has produced under a defined set of conditions. Proteomics has been used to identify novel bacterial vaccine candidates against several human pathogens. Fueled by growing DNA sequence information, the analysis of the proteome becomes a valuable and useful tool for antigen discovery. Much of information about immunogenic component can be derived from proteomics coupled to Western blotting, namely immunoproteomics. v In the present study, we report first immunoproteomics analysis to identify candidate antigens of B. pertussis for vaccine development. Different sera from mice, which were immunized or challenged with B. pertussis, were analyzed for reactivity by Western blot against whole cell extracts of B. pertussis Tohama and Saadet strains separated by 2-DE. We identified 15 immunogenic proteins of Bordetella pertussis as a total (60 kDa chaperonin, heat shock protein, serum resistance protein, putative substrate-CoA ligase, ATP-dependent protease, preprotein translocase secA subunit, S-adenosylmethionine synthetase, elongation factor Tu, RNA polymerase alpha subunit, ketol-acid reductoisomerase, pertactin, lysyl-tRNA synthetase, serum resistance protein, carbamoyl-phosphate synthase large chain, 30S ribosomal protein S1 subunit), 6 of which being identified as immunogenic in a pathogenic microbe (ATP-dependent protease, carbamoylphosphate synthase large chain, lysyl-tRNA synthetase, putative chromosome partition protein, preprotein translocase secA subunit, 30S ribosomal protein S1 subunit) and 5 identified as immunogenic for Bordetella pertussis (RNA polymerase alpha subunit, S-adenosylmethionine synthatase, putative substrate-CoA ligase, elongation factor Tu, ketol-acid reductoisomerase) for the first time.

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Lute, Kenneth D. "Costimulation and tolerance in T cell immunotherapy." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141850521.

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Golakai, Hawa Jande. "Identification of immune correlates of natural protection against tuberculosis in a population with a high incidence of latent infection." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/21776.

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Thesis (MScMed)--Stellenbosch University, 2008.
ENGLISH ABSTRACT: Setting This study was conducted in the Tygerberg area of Cape Town in South Africa. Background A third of the world’s population is latently infected with Mycobacterium tuberculosis, and correlates of protection against progression to active disease urgently need to be identified to facilitate the development of an effective vaccine against the disease. The production of IFN-γ is recognised as an immune correlate of protection from tuberculosis, but other immune regulators have been implicated in playing a significant role in protective immunity. The aims of this project were three-fold: (i) to identify promising TB vaccine candidates by screening a panel of novel MTB antigens, by stimulating whole blood cultures in vitro with the novel proteins and quantifying the level of IFN-γ production, (ii) to identify other cytokines and chemokines that may be immune correlates of protection using the Luminex fluorescent bead-based technique and (iii) to compare the performance of the two techniques. Methods Antigen Screening study Whole blood of 57 adult and adolescent participants defined as latently infected individuals was stimulated with a panel of 78 novel TB-specific, DosR- or RD1-encoded antigens. The 7-day culture supernatants were used in IFN-γ ELISA to quantify the level of IFN-γ production. Luminex Assay study Whole blood culture supernatants of 15 HIV negative, TST positive adults were used in the Luminex LINCO 21-plex cytokine assay. This was done to determine which of 21 cytokines, that may be LTBI-associated cytokines, were produced after stimulation with 9 TB-specific recombinant antigens, and to quantify their level of expression. Results In the antigen screening study, it was found the majority of the 78 proteins tested were able to induce a positive IFN-γ response. The classic TB antigens were used as controls, and the frequency of responses was highest after stimulation with ESAT-6 and TesatCFP10 (80 – 85% of responders). Ten latency antigens elicited an IFN-γ response in 19 – 45% of participants, and five reactivation antigens stimulated a positive reaction in 15 – 48% of responders. The category of antigens that elicited the most frequent and highest responses overall was the resuscitation-promoting factors (Rpf). Over 30% of participants responded to all 5 Rpfs, and the level of responses were equally divided in the low and moderate-to-high levels, with an additional 5% of responses in the high (>1000pg/ml) range. In the Luminex study, the positive stimulant TesatCFP10 consistently induced expression of most cytokines. In addition latency antigens Rv1733c, Rv0569 and Rv2029c also induced moderate-to-high level cytokine expression. A Th1-biased cytokine profile was observed, with the preferential expression of pro-inflammatory and cell-mediated cytokines like IFN-γ, TNF-α, IP-10, MIP1-α and G-CSF being produced. Th2 cytokines IL-4, IL-5, IL-13 and eotaxin were very poorly expressed or were not expressed at detectable levels. A very strong induction of IL-6, IL-8 and MCP-1 was observed, but this cytokine/chemokine association suggested contamination of the recombinant antigens with bacterial endotoxins. Conclusion In this study of latently infected individuals, the pattern of response observed for both assays is largely a Th1-biased expression profile. The whole blood ELISA method is a well-established assay for quantifying IFN-γ in culture supernatants, and has proven to be effective here. This study has demonstrated, in humans with LTBI, immune recognition of these novel MTB-specific antigens as illustrated by the positive IFN-γ levels induced after stimulation. The multiplex technology is also a very versatile and sensitive assay, capable of detecting multiple analytes simultaneously in one sample. The multiplex has been valuable here in identifying some antigens as potential vaccine candidates, and a subset of cytokines as potential immune mediators and prognostic indicators in TB infection.
AFRIKAANSE OPSOMMING: Studie-area Hierdie studie was gedoen in die Tygerberg area van Kaapstad in Suid-Afrika. Agtergrond ‘n Derde van die wêreld se bevolking is latent geïnfekteer met Mycobacterium tuberculosis en korrelate van beskerming teen die siekte moet geïdentifiseer word om die ontwikkeling van ‘n effektiewe enstof te fasiliteer. Die produksie van IFN-γ is welbekend as ‘n immuunkorrelaat van beskerming teen tuberkulose (TB), maar ander immuunreguleerders speel ook ‘n belangrike rol in beskermende immuniteit. Die doelwitte van hierdie projek was drievoudig: (i) om belowende TB-entstof kandidate te identifiseer deur die sifting van ‘n paneel van nuwe MTB antigene mbv die in vitro stimulasie van volbloed kulture, ii) om ander sitokiene en chemokiene as immuunkorrelate van beskerming te identifiseer deur van die Luminex fluorescent bead-based tegniek gebruik te maak, en (iii) om die twee tegnieke te vergelyk op grond van hul prestasie as prognostiese of siftings metodes in latente infeksie. Metodes Antigeen siftings studie Volbloed van 57 volwasse en adolessente deelnemers, geïdentifiseer as latent geïnfekteerde individue, was gestimuleer met ‘n paneel van 78 nuwe TB-spesifieke DosR- or R-gekodeerde antigene. Die 7-dae kultuur supernatante was gebruik in ‘n IFN-γ ELISA om die hoeveelheid IFN-γ produksie the kwantifiseer. Luminex assay studie Volbloed kultuur supernatante van 15 HIV negatiewe, TST positiewe volwassenes was gebruik in die Luminex LINCO 21-plex cytokine assay. Dit was gedoen om die tipes en hoeveelheid ander LTBI-geassosieerde sitokienes te identifiseer wat geproduseer word na stimulasie met 9 TB-spesifieke rekombinante antigene. Resultate In die antigeen siftings studie is gevind dat die meerderheid van die 78 getoetste proteïene ‘n positiewe IFN-γ reaksie kon induseer. Vir die kontroles was die frekwensie van reaksies die hoogste na stimulasie met ESAT-6 en TesatCFP-10 (80 – 85% van reageerders). Tien latensie antigene was gereeld herken deur 19 – 45% van deelnemers en vyf reaktiverings-antigene het ‘n positiewe reaksie in 15 – 48% van reageerders gestimuleer. Die kategorie van antigene wat die meeste en hoogste response veroorsaak het, was die resusitasie-promoterende faktors (Rpf). Meer as 30% van deelnemers het op al 5 Rpfs gereageer en die vlak van reaksies was gelyk verdeel in die lae en matig-tot-hoog vlakke, met ‘n addisionele 5% van reaksies in die hoë (>1000pg/ml) reeks. In die Luminex studie het die positiewe stimulant TesatCFP-10 konsekwent die positiewe uitdrukking van die meeste sitokiene geïnduseer. Saam met dit het die latente antigene Rv1733c, Rv0569 en Rv2029c ook matige-toe-hoë vlakke van sitokien uitdrukking geïnduseer. ‘n Th1-gebaseerde sitokien profiel was waargeneem, met die begunstigde uitdrukking van pro-inflammatoriese en sel-gemedieerde sitokiene soos IFN-γ, TNF-α, IP-10, MIP1-α en G-CSF. Th2 sitokiene IL-4, IL-5, IL- 13 en eotaksien was of baie sleg uitgedruk of onder naspeurbare vlakke uitgedruk. ‘n Baie sterk induksie van IL-6, IL-8 en MCP-1 was waargeneem, maar hierdie sitokiene/chemokiene assosiasie stel moontlik kontaminasie van die rekombinante antigene met bakteriële endotoksiene voor. Samevatting Die reaksiepatroon wat in hierdie studie tussen die twee toetse waargeneem is, was grootliks ‘n Th1-gebaseerde uitdrukkingsprofiel vir latente infeksie met TB. Die volbloed ELISA metode is a betroubare gevestigde toets vir die kwantifisering van IFN-γ in kultuur supernatante, wat ook in hierdie studie bewys is om effektief te wees. Hierdie studie het gedemonstreer dat die nuwe TB-spesifieke antigene effektief positiewe IFN-γ response in mense met LTBI induseer. Die multipleks tegnologie is ook ‘n baie veelsydige en sensitiewe toets, wat in staat is om veelvoudige analite gelyktydig in een monster te kan opspoor. In hierdie studie was dit veral waardevol in die identifisering van ander moontlike antigene as prognostiese kandidate en sitokiene as immuunbemiddelaars in TB-infeksie.

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KURAMOTO, GRACIELA B. "Estudo compartimental e dosimétrico do anti-CD20 marcado com 188Re." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26599.

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A radioimunoterapia (RIT) faz uso de anticorpos monoclonais conjugados com radionuclídeos emissores α ou β-, ambos para terapia. O tratamento baseia-se na irradiação e destruição do tumor, preservando os órgãos normais quanto ao excesso de radiação. Radionuclídeos emissores β- como 90Y, 131I, 177Lu e 188Re, são úteis para o desenvolvimento de radiofármacos terapêuticos e, quando associados a AcM como o Anti-CD20 são importantes principalmente para o tratamento de Linfomas Não Hodgkins (LNH). 188Re (Eβ- = 2,12 MeV; Eγ= 155 keV; t1/2 = 16,9 h) é um radionuclídeo atrativo para RIT. O Centro de Radiofarmácia do IPEN possui um projeto que visa a produção do radiofármaco 188Re-Anti-CD20. Com isso,este estudo foi proposto para avaliar a eficácia desta técnica de marcação para tratamento em termos compartimentais e dosimétricos. O objetivo deste trabalho consistiu na compararação da marcação do AcM anti-CD20 com 188Re com a marcação do anticorpo com 90Y, 131I, 177Lu e 99mTc (pelas suas características químicas similares) e 211At, 213Bi, 223Ra e 225Ac. Através do estudo de técnicas de marcação relatadas em literatura, foi proposto um modelo compartimental para avaliação de sua farmacocinética e estudos dosimétricos, de alto interesse para a terapia. A revisão de dados publicados na literatura, possibilitou demonstrar diferentes procedimentos de marcação, rendimentos de marcação, tempo de reação, impurezas e estudos de biodistribuição. O resultado do estudo mostra uma cinética favorável para o 188Re, pelas suas características físicas e químicas frente aos demais radionuclídeos avaliados. O estudo compartimental proposto descreve o metabolismo do 188Re-anti-CD20 através de um modelo compartimental mamilar, que pela sua análise farmacocinética, realizada em comparação aos produtos marcados com emissores β-: 131I-antiCD20, 177Lu-anti-CD20, o emissor γ 99mTc-anti-CD20 e o emissor α 211At-Anti-CD20, apresentou uma constante de eliminação de aproximadamente 0,05 horas-1 no sangue do animal. A avaliação dosimétrica do 188Re-Anti-CD20 foi realizada através de duas metodologias: pelo método de Monte Carlo e pelo uso de uma fonte pontual β- através da Fórmula de Loevinger via programa Excel. Através da Fórmula de Loevinger fez-se a validação do método de Monte Carlo para a dosimetria do 188Re-Anti-CD20 e dos demais produtos. As doses e as taxas de doses obtidas pelos dois métodos foram avaliadas em comparação à dosimetria do 90Y-Anti-CD20, 131I-Anti-CD20 e do 177Lu-Anti-CD20, obtidas pela mesma metodologia. O estudo de dose foi realizado utilizando modelos matemáticos considerando um camundongo nude de 25g, simulando diferentes tamanhos de tumor e diferentes formas de distribuição do produto dentro do animal. De acordo com os resultados obtidos, pela energia de emissão β-, 188Re-Anti-CD20 apresenta maior deposição de energia para tumores volumosos em relação aos demais produtos avaliados. Em uma simulação com 100% do produto captado pelo tumor, 89% da dose total manteve-se absorvida pelo tumor, preservando a integridade de ógãos críticos como coração (2%), pulmões (5%), coluna (4%), fígado (0,014%) e rins (0,0007%). Em uma simulação onde há uma biodistribuição do produto no organismo do animal, 38% da dose total é absorvida pelo tumor e >3% é absorvida pela coluna. Nessa situação mais próxima da realidade, a extrapolação dos dados para um humano de 70kg, mostrou que a dose absorvida no tumor corresponde a cerca de 33%; na coluna 7% e o coração receberia uma dose de 35% do total. A análise compartimental e dosimétrica apresentada neste trabalho, realizada através do uso de um modelo animal para o 188Re-Anti-CD20 mostra que o produto desenvolvido e apresentado em literatura é candidato promissor para a RIT.
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Benghiat, Fleur. "Contrôle de la réaction allogénique par les lymphocytes T régulateurs naturels." Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/216587.

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Le polymorphisme et le polygénisme des complexes majeurs d’histocompatibilité (CMH) limitent les succès de la transplantation. En effet, les disparités, tant d’antigènes mineurs que majeurs, exposent le patient transplanté au risque de rejet et imposent l’administration d’un traitement immunosuppresseur. Ce dernier affecte de façon non spécifique l’ensemble des réponses immunitaires et augmente le risque d’infections mortelles et de cancers. En outre, ce traitement ne semble pas prévenir le rejet chronique.

Des découvertes récentes ont confirmé l’existence de lymphocytes appelés régulateurs (Tregs) dont le rôle est de garantir l’homéostasie des réponses immunes afin qu’elles ne deviennent incontrôlées et pathologiques. Les Tregs classiquement décrits expriment de manière constitutive l’antigène CD4+, la chaîne alpha du récepteur de l’interleukine (IL)-2 (CD25) et le facteur de transcription Foxp3. Ils représentent 5 à 10% des lymphocytes CD4+ totaux. Les Tregs sont capables de réguler des lymphocytes alloréactifs et ont été décrits comme responsables du maintien de la tolérance d’allogreffe chez la souris. Mais jusqu'alors, les modèles employés pour démontrer l'importance des Tregs en transplantation utilisaient soit un traitement immunosuppresseur transitoire, soit des transferts de cellules T dans des souris lymphopéniques.

Toutefois, ces derniers ne permettent pas de distinguer l'effet des Tregs sur la prolifération homéostatique des lymphocytes effecteurs de leur effet sur la réponse allogénique.

Dans notre travail, nous montrons que les Tregs jouent un rôle prépondérant dans l’acceptation spontanée d’allogreffes en l’absence d’immunosuppresseur et en dehors d’un contexte lymphopénique chez la souris. En effet, la déplétion des Tregs du receveur par l’administration d’anticorps anti CD25 amplifie les réponses allogéniques de type Th1 et Th2 et, par conséquent, déclenche le rejet d’allogreffe. Les propriétés régulatrices des Tregs ne sont cependant pas illimitées. En effet, dans un second travail, nous décrivons, d’une part, leur incapacité à contrôler la production d’IL-17 par des lymphocytes CD4+CD25pos mémoires et, d’autre, part leur implication directe dans la différenciation de cellules Th17 au départ de lymphocytes CD4+CD25neg alloréactifs.

Nous concluons donc que si les Tregs naturellement présents chez le receveur jouent un rôle primordial dans la protection du greffon contre des réponses de type Th1 ou Th2, ils pourraient néanmoins favoriser une voie alterne du rejet d’allogreffe dépendante de l’IL 17.

/

Major histocompatibility complex (MHC) polymorphism is a major hindrance to transplantation success. Both minor and major antigen disparities between donor and recipient increase the risk of transplant rejection. This is thwarted by the administration of an immunosuppressive therapy that unspecifically affects all immune responses therefore increasing the risk of infections and cancers. Besides, this treatment does not seem to prevent chronic rejection.

Recent studies have confirmed the existence of lymphocytes called regulatory T cells (Tregs), whose role is to maintain the general immune homeostasis and to protect the individual from autoimmune diseases.

The classically described Tregs express constitutively the CD4 antigen, the alpha chain of the interleukin (IL)-2 receptor (CD25) and the transcription factor Foxp3. They represent 5 to 10% of total CD4+ T cells. Tregs are able to control alloreactive responses and were described to be responsible for the maintenance of allograft tolerance in mice. So far, the tolerogenic capacities of Tregs have been demonstrated either in mice treated with immunomodulatory antibodies (induced Tregs) or by adoptive co-transfer of Tregs and effector cells into lymphopenic mice. However, the latter has the disadvantage of not being able to distinguish the effect of Treg on lymphopenia-induced homeostatic proliferation from their effect on alloreactive responses.

Herein, we show that Tregs play a crucial role in spontaneously accepted allografts in the absence of immunosuppressive therapy and in non-lymphopenic condition. Indeed, the depletion of the recipient’s Tregs through the administration of an anti-CD25 antibody enhances type Th1 and type-Th2 allogeneic responses, consequently triggering allograft rejection. However, the regulatory properties of Tregs are not unlimited. Indeed, we found that Tregs are unable to control allogeneic IL-17 production by memory CD4+ T cells and are even necessary for de novo Th17 differentiation.

We conclude, therefore, that Tregs naturally present in the recipient play a critical role in protecting the allograft. Nevertheless, despite this context of regulation, IL-17-producing alloreactive T cells, beyond the control of Tregs, could mediate an alternative pathway of allograft rejection.
Doctorat en Sciences médicales
info:eu-repo/semantics/nonPublished

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Mécheri, Salah. "Contribution a l'etude de la modulation de la reaction anaphylactique grace a l'utilisation de constituants purifies du pollen de dactyle." Paris 7, 1988. http://www.theses.fr/1988PA077115.

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Wychowski, Czeslaw. "Expression de la proteine de capside vp1 du poliovirus dans les bacteries et dans les cellules animales : identification d'un epitope de neutralisation et caracterisation de sequences indispensables a l'accumulation de proteines dans le noyau." Paris 7, 1987. http://www.theses.fr/1987PA077173.

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Lo, Wen-Min, and 羅文敏. "The Study of Detection of the Antigen-Antibody Reaction by Pizeoelectric Crystal Biosensor." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/58618301665296958113.

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Newman, Peter M. "Antibody and antigen in heparin-induced thrombocytopenia /." 1999. http://www.library.unsw.edu.au/~thesis/adt-NUN/public/adt-NUN20001214.161838/index.html.

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Maynard, Jennifer Anne 1974. "Engineering antibody therapeutics : approaches to neutralizing bacterial toxins." 2002. http://hdl.handle.net/2152/11127.

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Maynard, Jennifer Anne. "Engineering antibody therapeutics approaches to neutralizing bacterial toxins /." 2002. http://wwwlib.umi.com/cr/utexas/fullcit?p3114782.

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Williams, David Collin. "A study of protein conformational dynamics in antigen : Antibody interactions /." 1997. http://wwwlib.umi.com/dissertations/fullcit/9738792.

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Blackler, Ryan J. "Structural investigations into conformational diversity, polyspecificity, and binding mechanisms of near-germline antibodies." Thesis, 2016. http://hdl.handle.net/1828/7305.

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The antibody response has evolved under constant pressure to recognize common pathogens and also remain adaptable to novel threats. Given the limited size of the germline antibody repertoire, adaptability requires that some antibodies must be polyspecific for multiple distinct antigens. Despite the profound importance of polyspecificity in the antibody response, the structural features that allow it are not well understood. Antibodies raised against glycoconjugates of Chlamydiaceae LPS oligosaccharides of the inner-core sugar Kdo (3-deoxy-d-manno-oct-2-ulosonic acid) have been shown to cross-react with several inner-core oligosaccharides through conserved recognition of single Kdo residues in a germline-encoded pocket, with additional sugars accommodated by flexible side-chains. Two of these antibodies, S25-2 and S25-39, were observed to bind several Kdo oligosaccharides with an identical binding site conformation, but adopted unique conformations of the heavy chain complementarity determining region loop 3 (CDR H3) in the absence of ligand. Conformational flexibility of germline antibodies is believed to facilitate polyspecificity by generating multiple unique binding sites in a single antibody. This thesis research further explores the conformational flexibility of the antibodies S25-2 and S25-39 to gain insight into mechanisms of antigen recognition and how this feature may allow polyspecificity. This was achieved first by solving structures of S25-39 from crystals grown in unique conditions to observe alternate CDR H3 conformations, and second by designing synthetic Kdo-based antigens so as both to inhibit interaction with the previously observed liganded conformation of S25-2 and S25-39 and to be accommodated by their observed unliganded conformations. These structures reveal an unprecedented level of structural diversity of CDR H3, notably including the exact ‘liganded’ conformation in the absence of ligand. This is the first direct structural evidence that CDR H3 can exist in a conformational equilibrium with antigen binding through a selection mechanism, as opposed to induced fit where antigen causes the observed conformational change. Definitive evidence for binding the synthetic antigens was not obtained, however the resulting structures revealed several additional unique conformations of CDR H3 suggesting that ligands can alter conformational equilibria during crystallization. A unique conformation was also observed with CDR H3 coordinating multiple iodide ions, revealing another potential source of polyspecificity with unique binding paratopes generated by ion coordination. Finally, the unparalleled level of conformational diversity observed for these antibodies highlights the challenges of antibody structure classification and prediction, and stresses the need for additional in-depth studies of conformational diversity and binding mechanisms to advance these fields for therapeutic application. This is the first targeted structural study of flexibility in antibodies and provides insight into their conformational dynamics and antigen-binding mechanisms. These are of fundamental importance in understanding antibody structure and function, a critical consideration in practical applications such as modelling and design of therapeutic or diagnostic antibodies.
Graduate
2019-11-27

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Sciammas, Roger. "Function and antigen specificity of the TCR [gamma][delta] cell response to HSV-1 infection /." 1997. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:9832198.

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Lin, Yu Ping, and 林玉瓶. "Study the Applications of Antigen-Antibody Related Reactions in Analytical Magnetapheresis." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/78372089670778989094.

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碩士
國立暨南國際大學
應用化學系
93
The thesis is divided into two parts. In Part I, analytical magnetapheresis was used to study the interaction of antigen and antibody. In Part II, we studied the dispersion of nanopowder（silica, SiO2）under different surfactants. Part I：Analytical magnetapheresis has become a useful separation technology, in recent years. It is mainly used for macro molecules（MW＞106）, colloids and particles. This technology was fast, simple, selective and nondestructive. This study used the gradient elution principle. It studied the interactions of Streptavidin-Biotin and IgG-Protein A in analytical magnetapheresis. Experimental parameters were studied under different conditions of the flow rate, injected particles and material channels. The Streptavidin-conjugated magnetic beads and IgG-conjugated magnetic beads can capture silica particles labeled with Biotin and Protein A in the separation channel under magnetic filed. The selectivity is high with controlled experiments. Part II：Nano-scale materials have some special physics properties. Nano-materials play a major role for their physics properties. Aggregation must be avoided for applications of nanopowder. We added surfactant into solution to improve the aggregation condition of silica nanopowder. We have tested several surfactants. Dispersion was improved with adding 0.01％ of FL-70 surfactant into solution.

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Hagembe, Juliana Liambaya. "Effect of antigenic site mutations on the binding specificity of an anti-hemagglutinin antibody to H3N2 influenza virus isolates." 2009. 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:1467107.

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Pyle, Emily Claire. "The kinetics of neutralizing anti-viral antibodies and the production of a T cell-dependent antibody response during vesicular stomatitis virus infection." 2008.

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Terrientes, S. Zilka I. "Study of the antigenicity of P. yoelii parasitized erythrocyte ghost antigens and their role in protection." Thesis, 1990. http://hdl.handle.net/10125/9440.

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Luo, Cheng-Ping [Verfasser]. "Detection of antibody antigen reactions using surface acoustic wave and electrochemical immunosensors / [presented by Cheng-Ping Luo]." 2004. http://d-nb.info/971863121/34.

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Kuo, Hsiao-Fen, and 郭曉芬. "Production and characterization of mouse monoclonal antibody specific reactive with ovarian cancer associated OVTA-1-1002 antigen." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/96319237267849112553.

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Greenwood, John Milton. "The production and characterization of monoclonal antibodies against K88 pili from porcine enterotoxigenic Escherichia coli." 1985. http://hdl.handle.net/2097/27447.

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Tomic, Jelena. "Aberrations in Cytokine Signaling in Leukemia: Variations in Phosphorylation and O-GlcNAcylation." Thesis, 2012. http://hdl.handle.net/1807/32829.

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Abstract:

Tumor-induced immunosuppression can occur by multiple mechanisms, each posing a significant obstacle to immunotherapy. Evidence presented in this dissertation suggests that aberrant cytokine signaling, as a result of altered metabolism of Chronic Lymphocytic Leukemia (CLL) cells, confers a selective advantage for tumor survival and growth. Cells from CLL patients with aggressive disease (as indicated by high-risk cytogenetics) were found to exhibit prolongation in Interferon (IFN)-induced STAT3 phosphorylation, and increased levels of reactive oxygen species (ROS) in these cells reflected these signaling processes. Changes in the relative balance of phospho-STAT3 and phospho-STAT1 levels, in response to combinations of IL-2 + Toll-like receptor (TLR)-7 agonist + phorbol esters, as well as IFN, were associated with the immunosuppressive and immunogenic states of CLL cells. In addition, immunosuppressive leukemic cells were found to express high levels of proteins with O-linked N-acetylglucosamine (O-GlcNAc) modifications, due to increased metabolic activity through the Hexosamine Biosynthetic Pathway (HBP), which caused impaired intracellular signaling responses and affected disease progression. A conclusion of the studies presented here is that the intrinsic immunosuppressive properties of leukemic cells may be overcome by agents such as Resveratrol that target metabolic pathways of these cells.

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Dissertations / Theses on the topic 'Antigen antibody reaction'

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