采用亚型测定、核苷酸和氨基酸序列测定和同源性分析等方法,观察了HIV1ⅢB毒株在实验室长期传代过程中包膜基因变异的情况。研究的毒株包括:经过实验室8年多连续使用而获得的毒株、在MT4细胞长期连续传代而获得的每间隔10代的毒株样品及多次更换宿主细胞传代而获得的毒株。主要结果有:(1)各种毒株包膜基因变异均不显著,核苷酸序列同源性均大于92%,变异距离均小于7.5%,且随着传代数增加核苷酸趋于稳定,代间同源性由92%上升至99%,而变异距离由7.5%下降为0.6%。(2)在传代过程中HIV1亚型保持稳定,各种毒株均为HIV1B3亚型。结果显示HIV在体外长期传代培养的过程中变异不大,遗传性状稳定,可能是体外生长的环境十分稳定,缺乏机体免疫学压力。结果也提示体外长期传代HIV毒株仍然适用于各种HIV的应用研究,用长期传代的方法发展HIV减毒活疫苗的可能性不大。

In order to understand the characteristics and rules of HIV diversity when passaged in vitro , the systematic study on the variation of env gene of HIV strain introduced from American in 1988 was carried out. Taking all the following strains as the objects: the 96 strain derived from the primary strain by continuous freeze thaw usage in laboratory for more than eight years; the 42?h strain derived from primary strain by serial passaging with continuous changing of host cell in MT4 and HelaCD4+ and the strains sampled from serial passaged primary strain in MT4 cell every ten generations, The pre DNA fragments of these HIV env gene were amplified by nested PCR. The fragment of 1?200 bp originated from the V1 V5 region was analyzed. The subtypes of these HIV strains were identified by Heteroduplexes Mobility Assay (HMA). The main results were: (1) the env gene diversity of all the strains were indistinctive, all the nucleotide homogeneous were greater than 92% and all the gene diversity distance were .