Minimal Levels of HIV-1 in Vaccinated & Exposed Persons

描述（由申请人提供）：1997年底，我们启动了一项研究，以确定血清阴性者中HIV-1感染的最低水平，这些人报告重复与HIV-1感染的伴侣发生高风险性接触，称为暴露血清阴性（ES）。 在10个具有可检测到的HIV-1特异性细胞毒性T淋巴细胞（CTL）应答的明确定义的ES个体中，我们证明了两个ES（附录A）中存在极低水平的HIV-1感染（范围：0.1 - 0.01拷贝/百万个细胞），远低于常规检测方法的检测限。 使用相同的方法，我们确定了在短暂病毒血症或疫苗保护的猕猴中SIV感染水平较低的平行证据。 最近，我们发现持续低水平的HIV-1感染的三个接种疫苗的人谁是短暂的病毒血症，通过常规检测。 这些发现表明，只有通过改进技术，对大量细胞进行数百或数千次PCR扩增和序列分析，才能在ES和接种疫苗的人中证明最低水平的HIV-1感染（MLHI）。 在这里，我们建议扩展我们的初步结果，以机械化的过程，并评估MLHI更严格地从NIH资助的疫苗试验，主要是艾滋病毒疫苗试验网络（HVTN）的ES和疫苗接种者之间的队列。 我们还将利用从我们的检测中分离的病毒或序列的可用性来表征突破性MLHI感染中的病毒基因型，并将这些特征与疫苗株进行比较。 具体目标是：1。 改进方法，以确定疫苗试验参与者和ES个体中短暂或持续的最低水平的HIV-1感染。 我们将通过常规病毒学、血清学或T细胞介导的免疫学检测，确定可能有短暂感染的人群中HIV-1的频率和复制状态。 2. 描述MLHI患者外周血和组织中存在的HIV-1毒株的基因型，并确定接种疫苗或重复暴露于HIV-1是否对HIV-1感染的最低减毒水平产生影响。 这些研究应有助于定义减弱和/或基本控制HIV-1感染所需的病毒学和免疫学特征，这是艾滋病疫苗开发的一个关键目标。

DESCRIPTION (provided by applicant): In late 1997, we initiated a study to identify minimal levels of HIV-1 infection in seronegative persons who reported repeated high-risk sexual exposures to HIV-1-infected partners, termed as exposed seronegative (ES). Among ten well-defined ES individuals with detectable HIV-1-specific cytotoxic T-lymphocytes (CTL) responses, we demonstrated presence of HIV-1 infection in two ES (Appendix A) at extraordinarily low levels (range: 0.1 - 0.01 copies per million cells) that are well below the detection limit of conventional assays. Using same methodologies, we identified parallel evidence for low levels of SIV infection in macaques that were transiently viremic or vaccine-protected by conventional testing. Most recently, we have found persistent low levels of HIV-1 infection in three vaccinated persons who were transiently viremic by conventional assays. These findings indicate that minimal levels of HIV-1 infection (MLHI) can be demonstrated in ES and vaccinated persons, only by improved technologies with hundreds or thousands of PCR amplifications and sequence analyses on large amounts of cells. Here, we propose to extend our preliminary results to mechanize the processes and to assess for MLHI more rigorously among our cohort of ES and vaccine recipients from NIH-funded vaccine trials, mainly the HIV Vaccine Trails Network (HVTN). We will also take advantage of the availability of virus or sequences isolated from our assays to characterize the genotype of virus in breakthrough MLHI infection and compare these characteristics with vaccine strains. The Specific Aims are: 1. To improve methodologies to identify transient or persistent minimal levels of HIV-1 infection in vaccine trial participants and ES individuals. We will ascertain the frequency and replication state of HIV-1 in persons who may have transient infection as indicated by conventional virologic, or serologic, or T cell-mediated immunologic assays. 2. To characterize the genotype of HIV-1 strains present in peripheral blood and tissues in MLHI persons and to determine if there is impact of vaccination or repeated exposures to HIV-1 on the attenuated minimal levels of HIV-1 infection. These studies should assist definition of virologic and immunologic characteristics required to attenuate and/or substantially control HIV-1 infection, a critical goal of AIDS vaccine development.