RESUMEN
OBJECTIVE: To study whether the porcine alpha1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte negatively expresses GT mRNA and resists to the cytotoxicity of nature antibody in human serum. METHODS: The porcine alpha1, 3 galactosyltransferase gene siRNA targeted vector (pPNTloxPGTsiRNA) were construct with pPNTloxPGT and pMXSV/U6 vector. Positive-negative selection was used to produce a heterozygous pPNTloxPGTsiRNA knockout (+/-) clone. The GT mRNA expressions were detected with northern blot. Complement-mediated NAb cytotoxicity after incubation of hepatocytes with NAbs and complement was determined using 3- (4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium(MTS, tetrazolium salt) colorimetric assay. RESULTS: The pPNTloxPGTsiRNA targeted porcine hepatocyte (+/-) negative express GT mRNA. Only 14% to 18% cytotoxicity can be detected at the highest serum concentration. The pPNTloxPGT targeted porcine hepatocyte (+/-) express GT mRNA just as the wild type porcine cells and the cytotoxicity are 77% to 83%. CONCLUSION: The porcine a1, 3 galactosyltransferase gene siRNA targeted heterozygous hepatocyte (+/-) negative express GT and resisted to nature antibody in human serum.