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dc.contributor.advisorBretscher, Peter A.en_US
dc.creatorMcKinstry, Karl Kaien_US
dc.date.accessioned2005-05-05T15:36:24Zen_US
dc.date.accessioned2013-01-04T04:30:26Z
dc.date.available2006-05-09T08:00:00Zen_US
dc.date.available2013-01-04T04:30:26Z
dc.date.created2005-05en_US
dc.date.issued2005-05-04en_US
dc.date.submittedMay 2005en_US
dc.identifier.urihttp://hdl.handle.net/10388/etd-05052005-153624en_US
dc.description.abstractSeveral variables have been found to affect the Th1/Th2 differentiation of newly activated CD4 T cells. This phenotype can be critical in determining effectiveness of immune responses. Experiments in this thesis were undertaken to better define the in-vivo cellular interactions involved in determining the Th1/Th2 phenotype of newly activated CD4 T cells.Lethally irradiated BALB/c mice reconstituted with a constant number of syngeneic, naive spleen cells were challenged with xenogeneic red blood cells (XRBC) conjugated to ovalbumin (OVA) and the Th1/Th2 phenotype of the anti-XRBC response assessed. Antigen-specific interferon-gamma (IFN-g) and interleukin-4 (IL-4) secreting cells obtained from spleens of immunized mice were enumerated by an ELISPOT assay; the relative number of IFN-g- and IL-4-producing cells is taken as a relative measure of Th1 and Th2 components of the response. When challenged with a ‘standard’ dose of XRBC-OVA, predominant Th1 responses are generated; when challenged with a ten-fold lower dose, such reconstituted mice do not generate significant responses. This adoptive transfer system was employed to explore further the relationships between quantitative changes in the dose of immunizing antigen and the number of responding antigen-specific CD4 T cells, and the Th1/Th2 phenotype of immune responses generated. Unprimed transgenic CD4 T cells specific for OVA can modulate the Th1/Th2 phenotype of the anti-XRBC response upon immunization with XRBC-OVA. Addition of a small number of naive transgenic spleen cells to the standard reconstituting population of normal spleen cells results in the generation of significant numbers of SRBC-specific Th2 cells when mice are challenged with a ‘standard’ dose, or can generate predominant Th1 responses when mice are challenged with a ten-fold lower dose. Transgenic cells only impact the Th1/Th2 phenotype of CD4 T cells specific for XRBC when OVA is linked to the XRBC. That CD4 T cells specific for different antigens cooperate only through the recognition of linked antigenic determinants has important implications for many aspects of immune regulation. Observations further show that thymocytes from transgenic mice can influence the XRBC-specific response phenotype in an identical manner as transgenic spleen cells, suggesting that previously polarized pro-Th1/Th2 cells are not required in the cooperative events influencing Th1/Th2 phenotype of newly activated CD4 T cells.These observations lead to a quantitative description, whereby antigen-mediated CD4 T cell cooperation can affect the Th1/Th2 phenotype of a primary antigen-specific immune response, and provide a context for further analysis at the molecular level.en_US
dc.language.isoen_USen_US
dc.subjectimmune regulationen_US
dc.subjectlinked recognitionen_US
dc.subjectCD4 T cellsen_US
dc.subjectin vivoen_US
dc.titleQuantitative analysis of antigen-mediated CD4 T cell - CD4 T cell cooperation determining the Th1/Th2 phenotype of a primary immune responseen_US
thesis.degree.departmentMicrobiology and Immunologyen_US
thesis.degree.disciplineMicrobiology and Immunologyen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelDoctoralen_US
thesis.degree.nameDoctor of Philosophy (Ph.D.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US
dc.contributor.committeeMemberOgunremi, Oladele A.en_US
dc.contributor.committeeMemberHoward, S. Peteren_US
dc.contributor.committeeMemberHavele, Calliopien_US
dc.contributor.committeeMemberGordon, John R.en_US
dc.contributor.committeeMemberDelespesse, Guyen_US


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