Studies on Establishment of Co-expression System and Function of Human Complement Regulatory Proteins MCP and CD59
人补体调节蛋白MCP、CD59共表达体系的构建及其功能研究

Recombinant expression vector pcDNA3-MCPCD59DP containing human membrane complement regulatory proteins(hCRPs) MCP and CD59 cDNA was constructed successfully by using two independent promoters.After transfected into NIH3T3 cells with calcium phosphate-DNA precipitate method,NIH3T3 pcDNA3-MCPCD59-DP transfectants were obtained by G418 selection.Extraneous genes integration was identified by PCR.The co-expression of human CD59 and MCP at both mRNA and protein levels was confirmed by using RT-PCR and Western blot analysis.Human MCP and CD59 cDNA were integrated in NIH3T3 pcDNA3-MCPCD59-DP genomic DNA after continuous 30 times passages,indicating that NIH3T3 pcDNA3-MCPCD59-DP were stable cell lines.Human complement-mediated cytolysis assays showed that NIH3T3 cells transfected stably with pcDNA3-CD59,pcDNA3-MCP,and pcDNA3-MCPCD59-DP were protected from C-mediated damage and co-expressed human MCP and CD59 provided more excellent protection against C-mediated attack as compared with either CD59 or MCP expressed alone.The dicistronic vector represents an effective and efficacy strategy to overcome C-mediated damage and has potential therapeutic value for effectively controlling complement activation and finally for preventing hyperacute rejection in clinical gene therapy.