In vitro characterization of human anti-porcine xenogeneic cellular immune responses / by Tia Shermaine Coleman Johnson.
| Author/creator | Coleman Johnson, Tia Shermaine author. |
| Other author | Verbanac, Kathryn M., degree supervisor. |
| Other author | East Carolina University. Department of Biology. |
| Format | Theses and dissertations |
| Production | 2001. |
| Description | vii, 89 leaves : color illustrations ; 28 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | Immunosuppressive drugs have proven very successful in alleviating the acute destruction of human tissue and organ allografts. However, due to a shortage of organ donors, scientists are now exploring the option of xenotransplantation, which is the transplantation of organs or tissues from one species to another. Since the future of clinical transplantation will undoubtedly include xenotransplantation, there is a need to examine human anti-pig cellular immune responses. The vascular endothelium is the principle target of xenograft rejection. The hypothesis of this thesis is that cellular interactions between human T cells and porcine endothelial cells (EC) result in release of human T cell cytokines and the induction of porcine EC cell surface molecules that promote xenogeneic cellular immune responses. The goal of this study was to use human anti-porcine mixed lymphocyte endothelial cell culture (MLEC) to investigate cell interactions, cross-species molecular compatibilities and the induction of human cytokines and porcine activation markers. For MLEC, human peripheral blood mononuclear cells (PBMC) or enriched CD4-I- T cells depleted of professional antigen presenting cells (APC) were cultured with resting pig aortic endothelial cells (PAEC) in the absence of exogenous cytokines. Human T cells proliferated strongly in response to PAEC, even in serum-free cultures, as measured by tritiated thymidine incorporation. Culture supernatants were assayed for human TNF-[alpha], IFN-[gamma] and IL-1[beta] by ELISA. High levels of the human Th1 cytokines TNF-[alpha] and IFN-[gamma] were detected only in cultures containing PAEC, with levels generally peaking on day four. CD4+ T cell-enriched, APC-depleted responders maintained proliferative anti-PAEC responses and cytokine release. PAEC were monitored for cell surface markers by flow cytometry. By day three, SLA Class II and VCAM-1 expression were induced in 92-96% PAEC. These results indicate that MLEC is an excellent in vitro model in which to study human antiporcine cellular responses. Human T cells are activated in response to direct antigen presentation by PAEC, which are also activated in this system. Specific cytokines, receptors and adhesion molecules appear to cross the xenograft barrier and play a critical role in T cell - PAEC interactions. Such interactions are likely to affect vascular endothelial cell (VEC) activation and immune responses to porcine xenografts in vivo. |
| General note | Presented to the faculty of Department of Biology. |
| General note | Advisor: Kathryn Verbanac |
| Dissertation note | M.S. East Carolina University 2001 |
| Bibliography note | Includes bibliographical references (leaves 83-89). |
| Genre/form | dissertations. |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Electronic Resources | Access Content Online | ✔ Available |