Lu Y, Ding J, Chen Y H
Research Center for Medical Science and Department of Biology, Tsinghua University, Ministry of Education, Beijing, PR China.
Immunopharmacol Immunotoxicol. 2001 Nov;23(4):487-94. doi: 10.1081/iph-100108595.
The failure of some candidate HIV-1 vaccines may result from inducing very weak neutralization activity against representative primary viral isolates. Based on our hypothesis that epitope-vaccine may be a new strategy to induce high levels of neutralizing antibodies against HIV-1, we designed two candidate multi-epitope-vaccines, EP1 [C-G-(ELDKWA-GPGRAFY)2-K] and EP2 (CG-GPGRAFY-G-ELDKWA-G-RILAVERYLKD), containing three neutralizing epitopes (GPGRAFY, ELDKWA and RILAVERYLKD) on HIV-1 envelope protein, and expected them to induce epitope-specific antibodies of predefined epitope-specificity. The two peptides were conjugated to carrier protein bovine serum albumin (BSA) and used for immunization of rabbits. Proteins were purified from the rabbit sera induced by both candidate multi-epitope-vaccines (EP1-BSA and EP2-BSA) through affinity chromatography with epitope-peptide-conjugated sepharose-column, and identified as antibodies in silver-staining and immunoblotting. These antibodies were demonstrated to recognize three neutralizing epitopes on peptides and the recombinant gp41 in ELISA-assay and immunoblotting. These results indicated that both candidate multi-epitope-vaccines could induce high levels of antibodies of predefined epitope-specificity which recognized a few of neutralizing epitopes on peptides and protein, providing experimental evidence for the new strategy to develop an effective neutralizing-antibody-based multi-epitope-vaccine against HIV-1.
一些候选HIV-1疫苗的失败可能是由于诱导出的针对代表性原发性病毒分离株的中和活性非常弱。基于我们的假设，即表位疫苗可能是诱导针对HIV-1的高水平中和抗体的新策略，我们设计了两种候选多表位疫苗，EP1 [C-G-(ELDKWA-GPGRAFY)2-K] 和EP2 (CG-GPGRAFY-G-ELDKWA-G-RILAVERYLKD)，它们在HIV-1包膜蛋白上包含三个中和表位（GPGRAFY、ELDKWA和RILAVERYLKD），并期望它们能诱导出具有预定义表位特异性的表位特异性抗体。这两种肽与载体蛋白牛血清白蛋白（BSA）偶联，并用于免疫兔子。通过用表位肽偶联的琼脂糖柱进行亲和层析，从两种候选多表位疫苗（EP1-BSA和EP2-BSA）诱导的兔血清中纯化蛋白质，并在银染和免疫印迹中鉴定为抗体。在ELISA检测和免疫印迹中，这些抗体被证明能识别肽和重组gp41上的三个中和表位。这些结果表明，两种候选多表位疫苗都能诱导出高水平的具有预定义表位特异性的抗体，这些抗体能识别肽和蛋白质上的一些中和表位，为开发一种有效的基于中和抗体的针对HIV-1的多表位疫苗的新策略提供了实验证据。
