Experimental Study On Immumosuppression Of Allotransplantation Induced By Transfusion Of Donor Apoptotic Cells

Experimental Study on Immumosuppression of Allotransplantation Induced by Transfusion ofDonor Apoptotic CellsPostgraduateChen JianfengTutor Prof. Gao YiAbstractBackground:Although transplantation is one of the most effective treatments for organ failure, its widespread clinical application is hindered by rejection. The holy goal for transplantation is how to induce immune tolerance of organ transplantation. Immunosuppressants are the only protocol of choice at present besides several side effects. Apoptosis is a kind of common physiological and pathologic phenomenon in organ that is commonly viewed as a silent cell death without damage to adjacent tissues, but the effect of apoptosis on immunity is unclear. We have demonstrated that donor apoptotic cells can actively regulate immune system.Objective:To investigate the influence of apoptotic cells on organ transplantation. To investigate the influence of transfusion of donor apoptotic spleen cells on allograft rejection and lymphocyte proliferation. To provide experimental evidences for establishing protocols induce transplantation tolerance.Methods:Apoptosis was induced by ultraviolet irradiation and detected by flowcytometry. Rat heterotopic transplantation Ultraviolet irradiated donor spleen cells were injected to recipients prior to allogeneic heart transplantation at 0, -3, -7 and -14 days. The allograft survival time and mixed lymphocyte reaction(MLR) was measured.Results:Ultraviolet irradiation can induce apoptosis effectively. In the allogeneic Wistar-to-SD combination, preoperative i .v. administration of-3-ultraviolet irradiated donor spleen cells led to a significant prolonged graft survival as compared with control, The best transfusion time was at ? days(45.13?9.43 versus 7.33 ?.87), while administration of normal or necrosis spleen cells did not(8.00?1.41, 9.75?.55). MLR was significantly inhibited in apoptotic cell transfused recipients.Conclusion: Preoperative administration of donor apoptotic cells not only actively inhibited MLR, but also prolonged graft survival. It is probably a feasible method to induce organ transplantation immune tolerance by donor apoptotic cells.