Clinical Significance of HIV Replication Fitness

描述（由申请人提供）：HIV复制适合度，我们将其定义为HIV分离物相对于参考HIV菌株在体外的生长速度，已被认为是HIV感染临床结果的重要预测指标。HIV复制适应度的临床意义仍然存在争议，主要是因为在衡量相对复制适应度的最佳方法上没有达成共识。对于使用从患者外周血培养的全病毒进行适应度分析是否比使用重组病毒更好，以及单周期分析是否能检测到与多周期生长竞争分析相同的特性，争论仍然存在。我们开发了一种重组病毒，多周期生长竞争试验来测量HIV在细胞培养中的复制适应性。在本试验中，使用流式细胞术定量感染细胞的比例。我们已经修改了该检测方法，以测量病毒复制单周期中的相对复制适合度，并且还将修改生长竞争检测方法，以测量完整（“完整”）临床分离株的复制适合度。这些试验利用类似的病毒载体，并将量化病毒复制使用相同的方法。然后，我们将处于一个独特的位置来评估这些适应度分析是如何比较的，并确定这些测量复制适应度的方法中哪一种与临床结果最相关。为了实现这些目标，我们将实现以下具体目标：(1)开发和评估多周期重组病毒试验，以测量HIV在体外的复制适应性。(2)建立并评估单周期重组病毒试验，以测量HIV在体外的复制适应性。(3)开发并评估一种多周期全病毒检测方法，以测量HIV在体外的复制适应性。(4)确定HIV-1复制适应度是否与治疗失败期间的病毒载量反弹或近期原发性HIV感染后的病毒载量设定点相关。相关性：我们研究的总体目标是确定测量HIV生长速度的测试是否可以预测HIV病毒载量水平。如果这些研究取得成功，他们可以确定有助于预测艾滋病毒感染患者临床结果的测试。

DESCRIPTION (provided by applicant): HIV replication fitness, which we will define as the growth rate of an HIV isolate relative to a reference HIV strain in vitro, has been proposed to be an important predictor of clinical outcome in HIV infection. The clinical significance of HIV replication fitness continues to be controversial, primarily because there is no consensus on the best way to measure relative replication fitness. Arguments persist as to whether fitness assays, using whole virus cultured from patient PBMCs, are preferable to those using recombinant viruses, and whether single cycle assays detect the same properties as multiple-cycle growth competition assays. We have developed a recombinant virus, multiple-cycle growth competition assay to measure HIV replication fitness in cell culture. In this assay, the proportion of infected cells is quantified using flow cytometry. We have modified this assay to measure relative replication fitness during a single cycle of virus replication, and will also modify the growth competition assay to measure replication fitness in intact ("whole") clinical isolates. These assays utilize similar viral vectors, and will quantify viral replication using the same methodology. We will then be in a unique position to evaluate how these fitness assays compare, and determine which of these approaches to measure replication fitness best correlates with clinical outcome. In order to achieve these goals we will accomplish the following specific aims: (1) Develop and evaluate a multiple-cycle recombinant-virus assay to measure HIV replication fitness in vitro. (2) Develop and evaluate a single-cycle recombinant-virus assay to measure HIV replication fitness in vitro. (3) Develop and evaluate a multiple-cycle whole-virus assay to measure HIV replication fitness in vitro. (4) Determine whether HIV-1 replication fitness, as measured using these three assays, correlates with viral load rebound during treatment failure or viral load set point after recent primary HIV infection. Relevance: The overall goal of our studies is to determine whether tests that measure how rapidly HIV grows can predict HIV viral load level. If these studies are successful, they could identify tests that could help predict clinical outcomes for HIV-infected patients.