Accommodated organs can survive in the presence of anti-organ antibodies and complement. Heme oxygenase-1 （HO-1） is essential to ensure accommodation in concordant xenotransplant models. However, whether induction o...Accommodated organs can survive in the presence of anti-organ antibodies and complement. Heme oxygenase-1 （HO-1） is essential to ensure accommodation in concordant xenotransplant models. However, whether induction of HO-1 over-expression could protect porcine endothelial cells （PECs） against human xenoantibodies and complement-mediated lysis and induce an in vitro accommodation is still unknown. The SV40-immortalized porcine aorta-derived endothelial cell line （iPEC） was pre-incubated with 20, 50, or 80 μmol/L of cobalt-protoporphyrins IX （CoPPIX） for 24 h, and the HO-1 expression in iPECs was analyzed by using Western blotting. CoPPIX-treated or untreated iPECs were incubated with normal human AB sera, and complement-dependent cytotoxicity （CDC） was measured by both flow cytometry and lactate dehydrogenase （LDH） release assay. In vitro treatment with CoPPIX significantly increased the expression of HO-1 in iPECs in a dose-dependent manner. Over-expression of HO-1 was successfully achieved by incubation of iPECs with either 50 or 80 μmol/L of CoPPIX. However, HO-1 over-expression did not show any protective effects on iPECs against normal human sera-mediated cell lysis. In conclusion, induction of HO-1 over-expression alone is not enough to pro- tect PECs from human xenoantibodies and complement-mediated humoral injury. Additionally, use of other protective strategies is needed to achieve accommodation in pig-to-primate xenotransplantation.展开更多
基金supported by the Program for New Century Excellent Talents in University (No. NCET-06-0637)
文摘Accommodated organs can survive in the presence of anti-organ antibodies and complement. Heme oxygenase-1 （HO-1） is essential to ensure accommodation in concordant xenotransplant models. However, whether induction of HO-1 over-expression could protect porcine endothelial cells （PECs） against human xenoantibodies and complement-mediated lysis and induce an in vitro accommodation is still unknown. The SV40-immortalized porcine aorta-derived endothelial cell line （iPEC） was pre-incubated with 20, 50, or 80 μmol/L of cobalt-protoporphyrins IX （CoPPIX） for 24 h, and the HO-1 expression in iPECs was analyzed by using Western blotting. CoPPIX-treated or untreated iPECs were incubated with normal human AB sera, and complement-dependent cytotoxicity （CDC） was measured by both flow cytometry and lactate dehydrogenase （LDH） release assay. In vitro treatment with CoPPIX significantly increased the expression of HO-1 in iPECs in a dose-dependent manner. Over-expression of HO-1 was successfully achieved by incubation of iPECs with either 50 or 80 μmol/L of CoPPIX. However, HO-1 over-expression did not show any protective effects on iPECs against normal human sera-mediated cell lysis. In conclusion, induction of HO-1 over-expression alone is not enough to pro- tect PECs from human xenoantibodies and complement-mediated humoral injury. Additionally, use of other protective strategies is needed to achieve accommodation in pig-to-primate xenotransplantation.
