HUMORAL AND CELLULAR IMMUNE RESPONSE TO HIV FOR VACCINE DEVELOPMENT

这个项目的目的是描绘免疫反应，以人类 免疫缺陷病毒（HIV），并确定病毒的亚片段， 引发保护性免疫我们正在研究体液和细胞 对HIV-1和HIV-2的免疫反应;对猿免疫缺陷的研究 病毒是有计划的。我们首先关注的是体液免疫反应， 调查HIV中和抗体。以前的研究定位了一个主要的 中和表位至病毒gp120的V3环。横 使用匹配血清和病毒的扎伊尔队列的中和研究 正在分析分离株的V3环序列。的数量 将确定限定地理区域内的"血清型"。结果 这些研究将有助于设计一个共同的表位， 广泛反应的中和抗体在未来的疫苗。剥削 体外免疫选择使我们能够识别 交替中和表位和病毒包膜区对于 传染性广泛分析单一免疫选择变异病毒， 抵抗30%中和亲本的血清的中和 病毒，已经表明，在跨膜蛋白的点突变， 引起构象变化，改变中和表位， 另一个网站。选择和分析额外的变体，使用 IIIB和MN原型HIV-1分离株的感染性分子克隆， 的ISY HIV-2分离株将允许描绘额外的病毒 包膜区域在病毒-宿主相互作用中很重要。评估 感染或免疫猕猴的HIV-2中和抗体应答 正在进行中这种猕猴模型也被用于识别病毒表位 其引发细胞介导的免疫。细胞增殖测定和铬 针对HIV-2基因的细胞毒性T淋巴细胞释放试验 牛痘构建体中的产物以及合成肽 代表推定的病毒表位。细胞毒性T细胞的克隆 将有助于定位引起保护性细胞介导的 免疫反应。

This project aims to delineate immunologic responses to the human immunodeficiency viruses (HIVs), and to identify viral subfragments able to elicit protective immunity. We are investigating humoral and cellular immune responses to HIV-1 and HIV-2; studies with simian immunodeficiency virus are planned. We first focused on the humoral immune response, investigating HIV neutralizing antibody. Previous studies localized a major neutralizing epitope to the V3 loop of the viral gpl2O. Cross neutralization studies of a Zairian cohort using matched sera and viral isolates are being analyzed with regard to V3 loop sequences. The number of "serotypes" within a restricted geographic area will be determined. Results of these studies will assist design of a consensus epitope for elicitation of broadly reactive neutralizing antibody in future vaccines. Exploitation of in vitro immune selection has allowed us to pursue identification of alternate neutralizing epitopes and viral envelope regions important for infectivity. Extensive analysis of a single immune selected variant virus, resistant to neutralization by 30% of sera which neutralize the parental virus, has suggested that a point mutation in the transmembrane protein caused a conformational change, altering a neutralization epitope at another site. Selection and analysis of additional variants using the infectious molecular clones of the IIIB and MN prototype HIV-1 isolates and of the ISY HIV-2 isolate will allow delineation of additional viral envelope regions important in viral-host interactions. Assessment of the HIV-2 neutralizing antibody response in infected or immunized macaques is underway. This macaque model is also being used to identify viral epitopes which elicit cell mediated immunity. Cell proliferation assays and chromium release assays for cytotoxic T-lymphocytes are directed against HIV-2 gene products in vaccinia constructs as well as synthetic peptides representative of putative viral epitopes. Cloning of cytotoxic T-cells will facilitate mapping of epitopes which elicit protective cell mediated immune responses.