人类免疫缺陷病毒1型(HIV-1)糖蛋白gp120部分糖基化位点突变对其抗原性影响

目的 研究HIV-1包膜糖蛋白gp120特定糖基化位点突变后对gp120抗原性的影响,并推测糖基化位点突变对结构的影响.方法 采用连接PCR方法,将获得的野生型gp120中选定N糖基化位点的Asn定点突变为Cln,使该位点去糖基化,构建DNA疫苗,免疫小鼠,ELISA检测鼠血清中的抗体,进行统计学分析,推测糖基化位点突变对gp120抗原性和结构的影响.结果 2组糖基化位点突变的gp120诱发非V3特异性抗体的能力较之野生型gp120有明显提高,但诱发V3特异性抗体能力没有显著提高,7个位点突变的gp120诱发V3特异性抗体能力有很大降低.结论 gp120部分糖基化位点的突变在一定程度上能提高或改变gp120的抗原性,这可能由突变导致的构象变化和/或糖基化寡糖链移除使原来被遮盖的抗原表位暴露引起.

Antigenicity analysis of gp120 with partial mutation of glycosylation sites

Objective To study the effect of partial glycosylation site deletion of gp120 on the antigenic- ity of gp120 and to evaluate the conformational change.Methods Site directed mutation(Ash-Gln)of wild type gp120 was performed by ligation PCR.The wild type gp120 and mutated gp120 were ligated to expression vectors and to immunize mice.Affection on antigenicity and conformation of gp120 that induced by deletion of glycosylation sites was accessed by statistical analysis of ELISA result.Results Compared with wild type gp120,two of three mutated groups induced a significantly increased non-V3 specific antibody.But the deletion of glycosylation sites did not increase the ablity of inducing V3 specific antibody.Significantly decresased V3 specific antibody was ob- served in the group that had been deleted 7 glycosylation sites.Conclusion Partial deletion of glycosylation sites can increase or change the antigenicity of gp120,these results may be caused by conformational changing and/or epitope exposure.