Broadly Neutralizing Monoclonal Antibodies Against HIV-1

描述（由申请人提供）：本项目的长期目标是鉴定广泛识别HIV-1包膜糖蛋白（Env）并在体外阻断感染的新型单克隆抗体（mAb），以指导疫苗开发。这一目标将在没有抗逆转录病毒治疗的情况下控制其感染的HIV-1感染者的当地队列中实现（JAIDS，50：403-8，2009）。这些个体中约13%具有循环广泛中和抗体，为我们的研究提供了研究人群。我们的方法的关键要素是开发一种新的测定来普查Env特异性记忆B细胞克隆（BMem），其允许快速和直接克隆由这些细胞表达的抗体的全长分子克隆（PNAS，106：3952-7，2009）。该方法允许使用在细胞表面上表达的天然寡聚HIV-1包膜糖蛋白（Env）和通过直接中和假病毒进行克隆鉴定。Env反应性克隆用于产生mAb，其将被评估表位特异性和中和宽度。该信息将用于检验以下假设：中和宽度由单克隆或少克隆反应决定，而不是由中和特异性马赛克组成的多克隆反应，所述单克隆或少克隆反应由一种或极少数中和特异性组成。有两个具体目标。目的1-开发来自具有持续的广泛中和抗体应答的NVS的Env特异性BMem的克隆特异性谱-将通过有限稀释分析、mAb分离和表位作图来确定抗Env应答的克隆特异性谱，以鉴定广泛中和mAb。目的-2-比较血浆抗体和代表BMem完整克隆谱的mAb之间的中和宽度，以确定必须合并的mAb数量，以重建循环抗体池的中和谱。将使用标准化假病毒测定法测定mAb的中和宽度。该数据将用于确定正在进行的广泛中和抗体应答的克隆性。这一目的将检验以下假设：中和宽度由单克隆或少克隆反应决定，而多克隆反应由一种或极少数中和特异性组成，而多克隆反应由一系列中和特异性组成。 公共卫生相关性：这项研究与公共卫生有关，因为它试图了解感染艾滋病病毒的人如何做出保护性免疫反应。这些信息将有助于指导艾滋病病毒疫苗的研制。

DESCRIPTION (provided by applicant): The long-term goal of this project is to identify novel monoclonal antibodies (mAbs) that broadly recognize the HIV-1 envelope glycoprotein (Env) and block infection in vitro to guide vaccine development. This goal will be pursued in local cohorts of HIV-1 infected individuals who control their infections in the absence of anti-retroviral therapy (JAIDS, 50:403-8, 2009). Approximately 13% of these individuals have circulating broadly neutralizing antibodies providing the study population for our studies. A key element of our approach is the development of a new assay to census Env-specific memory B cell clones (BMem) that allows the rapid and direct cloning of full-length molecular clones of the antibodies expressed by these cells (PNAS, 106:3952-7, 2009). This method permits clone identification using native oligomeric HIV-1 envelope glycoproteins (Env) expressed on cell surfaces and by direct neutralization of pseudoviruses. Env-reactive clones are used to produce mAbs that will be evaluated for epitope specificity and neutralization breadth. This information will be used to test the hypothesis that neutralization breadth is determined by monoclonal or pauciclonal responses comprised of one or a very few neutralizing specificities as opposed to a polyclonal response comprised of a mosaic of neutralizing specificities. There are two specific aims. Aim 1- To develop clonal specificity profiles of Env-specific BMem from NVS who have ongoing broadly neutralizing antibody responses- Clonal specificity profiles of anti-Env responses will be determined by limiting dilution analysis, mAb isolation, and epitope mapping to identify broadly neutralizing mAbs. Aim-2- To compare neutralization breadth between plasma antibodies and mAbs representing a full clonal profile of BMem to determine the number of mAbs that must be pooled to reconstruct the neutralization profile of the circulating antibody pool. Neutralization breadth of mAbs will be determined using standardized pseudovirus assays. This data will be used to determine the clonality of an ongoing broadly neutralizing antibody response. This aim will test the hypothesis that neutralization breadth is determined by monoclonal or pauciclonal responses comprised of one or a very few neutralizing specificities as opposed to a polyclonal response comprised of a mosaic of neutralizing specificities. PUBLIC HEALTH RELEVANCE: This research is relevant to public health in that it seeks to understand how people who are infected with the AIDS virus make protective immune responses. This information will help guide the development of a vaccine against the AIDS virus.