Objective To study the effects of liver specific antigen(LSA)on liver allotransplantation rejection. Methods Orthotopic liver transplantation was performed in this study. GroupⅠ: syngeneic control(Wistar-to-Wistar); ...Objective To study the effects of liver specific antigen(LSA)on liver allotransplantation rejection. Methods Orthotopic liver transplantation was performed in this study. GroupⅠ: syngeneic control(Wistar-to-Wistar); GroupⅡ: acute rejection(SD-to-Wistar). GroupIII: thymic inoculation of SD rat LSA day 7 before transplantation. The observation of general condition and survival time, rejection grades and the NF-кB activity of splenocytes were used to analyze severity of acute rejection and immune state of animals in different groups. Results The general condition of groupⅠwas fair post transplantation with no sign of rejection. All recipients of group Ⅱ died within days 9 to 13 post transplantation with median survival time of 10.7 ±1.37 days. As for group III, 5 out of 6 recipients survived for a long period with remarkably better ge-neral condition than that of group Ⅱ. Its rejection grades were significantly lower than groupⅡ(P < 0.05).NF-кB activity was only detected in groupⅠbetween days 5 and 7 after transplantation, whereas highactivity of NF-кB was detected at all points in group Ⅱ and low NF-кB activity was detected in group III which was significantly lower than that of group Ⅱ(P < 0.05). Conclusions LSA is an important transplantation antigen directly involved in the immunorejection of liver transplantation. Intrathymic inoculation of LSA can alleviate the rejection of liver allotransplantation,grafts survive for a period of time thereby, allowing a novel way to liver transplantation immunotolerance.展开更多
The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell mediated acute allograft rejection. Besides the int...The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell mediated acute allograft rejection. Besides the interaction of CD3/TCR complex with Ag/MHC complex presented on antigen presenting cells, a complete T cell activation and proliferation requires a second costimulatory signal. The interaction of CD28/CTLA 4 and B7 is a major costimulatory pathway for T Cell activation. Inhibition of this pathway results in development of antigen specific unresponsiveness and clonal anergy.In present study,the biologic function of anti CD28 monoclonal antibody and its Fab fragment were investigated in vitro and in vivo.The results indicate that mAbCD28 and its Fab fragments could promote the functional recovery of allografts and prolong the graft survival,but could not reverse the acute rejection or induce transplantation tolerance in the rat PTG allograft model. We also found that peripheral TNF α level and NK cell activity were suppressed in the presence of mAbCD28 and its Fab fragments for a relatively long time after PTG transplantation.展开更多
文摘Objective To study the effects of liver specific antigen(LSA)on liver allotransplantation rejection. Methods Orthotopic liver transplantation was performed in this study. GroupⅠ: syngeneic control(Wistar-to-Wistar); GroupⅡ: acute rejection(SD-to-Wistar). GroupIII: thymic inoculation of SD rat LSA day 7 before transplantation. The observation of general condition and survival time, rejection grades and the NF-кB activity of splenocytes were used to analyze severity of acute rejection and immune state of animals in different groups. Results The general condition of groupⅠwas fair post transplantation with no sign of rejection. All recipients of group Ⅱ died within days 9 to 13 post transplantation with median survival time of 10.7 ±1.37 days. As for group III, 5 out of 6 recipients survived for a long period with remarkably better ge-neral condition than that of group Ⅱ. Its rejection grades were significantly lower than groupⅡ(P < 0.05).NF-кB activity was only detected in groupⅠbetween days 5 and 7 after transplantation, whereas highactivity of NF-кB was detected at all points in group Ⅱ and low NF-кB activity was detected in group III which was significantly lower than that of group Ⅱ(P < 0.05). Conclusions LSA is an important transplantation antigen directly involved in the immunorejection of liver transplantation. Intrathymic inoculation of LSA can alleviate the rejection of liver allotransplantation,grafts survive for a period of time thereby, allowing a novel way to liver transplantation immunotolerance.
文摘The activation of T cells to differentiate and to proliferate is an essential step in the immune response to antigen, especially in cell mediated acute allograft rejection. Besides the interaction of CD3/TCR complex with Ag/MHC complex presented on antigen presenting cells, a complete T cell activation and proliferation requires a second costimulatory signal. The interaction of CD28/CTLA 4 and B7 is a major costimulatory pathway for T Cell activation. Inhibition of this pathway results in development of antigen specific unresponsiveness and clonal anergy.In present study,the biologic function of anti CD28 monoclonal antibody and its Fab fragment were investigated in vitro and in vivo.The results indicate that mAbCD28 and its Fab fragments could promote the functional recovery of allografts and prolong the graft survival,but could not reverse the acute rejection or induce transplantation tolerance in the rat PTG allograft model. We also found that peripheral TNF α level and NK cell activity were suppressed in the presence of mAbCD28 and its Fab fragments for a relatively long time after PTG transplantation.
