Role of Tetraspan Glycoproteins (CD63) HIV Replication

描述（由申请人提供）：HIV感染原代人细胞通常需要Env gp 120与原代受体CD 4和趋化因子受体（CCR 5或CXCR 4）相互作用，然后是Env gp 41诱导的融合。其他因素和过程的参与是可能的，其重要性可能不同的主要靶细胞，巨噬细胞（M？）和T细胞。在筛选骨髓特异性单克隆抗体（mAb）文库时，发现抗CD 63 mAb可阻断HIV进入原代M？，而不是T细胞。CD 63是四跨膜蛋白膜糖蛋白家族的成员，现在与HIV感染（MS#1）有关，并且其他四跨膜蛋白与HTLV-I（CD 82）、FIV（CD 9）和丙型肝炎病毒（CD 81）的感染有关。最近的研究表明，包括CD 63第二胞外环（EC2）的GST融合蛋白具有抑制作用，这进一步支持了CD 63在HIV感染中的特异性作用。自上次提交以来的新数据也表明CD 63在HIV内体加工中的作用，因此我们将研究早期事件以及HIV生命周期后期发生的事件，以更全面地描述CD 63在HIV感染中的潜在作用。这些研究可能会导致新的抗逆转录病毒疗法的发展。我们将在五年内实现这些目标：目标1。为了检验这一假设，即CD 63参与早期的艾滋病毒复制事件，我们将调查病毒的摄取和启动逆转录在M？和T细胞/细胞系。目标2.为了检验原发性M？感染通常需要CD 63的假设，以及在T细胞/细胞系中，我们将评估病毒蛋白，特别是Gag（以及Env）的运输和组装，其中使用和不使用小抑制RNA（siRNA）进行CD 63沉默。我们还将沉默各种Rab蛋白，这些蛋白是通过内体途径运输细胞（和病毒）蛋白的细胞GTP酶，以确定受CD 63影响的HIV运输步骤。目标3。为了验证CD 63在M？(and其他细胞）的感染，我们将评估B亚型和非B亚型毒株的抗CD 63和CD 63-EC 2易感性，包括仅使用CCR 5（R5）、仅使用CXCR 4（X4）或双嗜性毒株（R5 X4）的那些。

DESCRIPTION (provided by applicant): HIV infection of primary human cells typically requires interaction of Env gp120 with both the primary receptor CD4 and a chemokine receptor, either CCR5 or CXCR4, followed by Env gp41-induced fusion. Involvement of other factors and processes are likely, and their importance may differ between the principle target cells, macrophages (M?) and T-cells. Upon screening of a myeloid-specific monoclonal antibody (mAb) library, anti-CD63 mAb was found to block HIV entry into primary M?, but not T-cells. CD63 is a member of the tetraspanin membrane glycoprotein family, now implicated in HIV infection (MS #1), and other tetraspanins have been implicated in infection with HTLV-I (CD82), FIV (CD9) and Hepatitis C virus (CD81). Recent studies have shown inhibition with a GST fusion protein that includes the CD63 second extracellular loop (EC2), which further supports a specific role for CD63 in HIV infection. New data since the last submission also suggests a role for CD63 in endosomal processing of HIV, and so we will look at both early events, as well as events that occur later in the HIV life cycle, to more fully delineate the potential role of CD63 in HIV infection. These studies may lead to development of novel antiretroviral therapies. We will pursue these aims over five years: Aim 1. To test the hypothesis that CD63 is involved with early HIV replication events, we will investigate virus uptake and initiation of reverse transcription in M? and T cells/cell lines. Aim 2. To test the hypothesis that CD63 is generally required for infection of primary M?, as well at T cells/cell lines, we will assess trafficking and assembly of viral proteins, particularly Gag (and also Env) with and without CD63 silencing with small inhibiting RNAs (siRNA). We will also silence varions Rab proteins, which are cellular GTPases that traffic cellular (and viral) proteins through endosomal pathways in order to identify steps of HIV trafficking affected by CD63. Aim 3. To test the hypothesis that CD63 plays a role in infection of M? (and other cells) by diverse primary HIV 1 strains, we will assess anti-CD63 and CD63-EC2 susceptibility of both subtype B and non-subtype B strains, including those that use CCR5 exclusively (R5, CXCR4 exclusively (X4) or dual-tropic strains (R5X4).