摘要
为了深入研究乙型肝炎病毒S基因变异所致的包膜抗原抗原性的改变,从含HBV DNA双拷贝的质粒载体pEcob6,获得一个837bp的HBV-S基因片段,将其插入至载体pBluescript KS^+的SmaI位点,通过体外寡核苷酸介导的人工定点突变分别获得第145位、126位和第145位+126位氨基酸三种S基因变异型。然后将这些S基因变异片段克隆到真核表达载体pMEp4上。
Amino acid 145 , 126 and 145 + 1 26 mutants of HBaAg were obtained by oligonucleotide-mediated site directed mutagenesis from a vector containing double copes of HBV DNA. The mutant genes of HBsAg were inserted into a eukaryotic expression vector pMEp4. The expression vector containintg the mutant genes were transfected into a human hepatocellular carcinoma cells (HepG2 ) ,and recombinant proteins were expressed . All three mutants had reactivity with polyclonal antibody against HBsAg in Western blot , but failed to react with monoclonal antibody against 'a' epitopes of HBsAg except aa 126 mutant in ELISA. That indicates the mutation in aa 145 of HBsAg is critical for escaping protective antibody to HBV in nature.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
1996年第2期130-132,共3页
Chinese Journal of Microbiology and Immunology