Viral control mechanisms of HIV-specific T cells in HIV-infected lymph node

 描述（由申请人提供）：乳突组织是HIV储存库最初播种、传播和长期维持的关键部位。因此，了解淋巴组织内直接控制和消除HIV所需的T细胞特性和机制对于HIV治愈，根除和疫苗议程至关重要。该提议背后的核心问题是淋巴结（LN）中的HIV特异性CD 8+和CD 4 + T细胞是否具有或能够获得控制或消除HIV感染细胞所需的功能能力。这些研究是基于这样的概念，即细胞毒性CD 8+（和CD 4+）T细胞通常不存在于HIV受试者或没有潜在炎症状况的受试者的淋巴结中。直觉上，这是有生物学意义的：为什么LN需要细胞毒性T细胞？LN中的细胞毒性T细胞（CD 8+或CD 4+）将部分地起到消除抗原呈递细胞的作用，从而抑制免疫应答。然而，在HIV感染、HIV疫苗，尤其是基于HIV治愈的策略中，LN内的细胞毒性HIV特异性CD 8 + T细胞将需要控制或消除病毒感染的CD 4 + T细胞。我们的初步数据显示，慢性感染受试者LN中存在失调的穿孔素+HIV特异性CD 8 + T细胞，CXCR 5表达非常低，CXCR 5是进入淋巴滤泡所需的标志物，HIV感染的CD 4 + T细胞集中在淋巴滤泡中。出乎意料的是，抗逆转录病毒治疗似乎逆转了这一点，LN CD 8 + T细胞上CXCR 5表达增加，但穿孔素水平降低。这与人们所希望的艾滋病毒“休克和杀死”治疗策略的“杀死”组成部分相反。我们的研究结果总体上表明，LN CD 8 + T细胞与驱动HIV治疗和疫苗领域的传统智慧相比具有根本不同的功能能力。这些考虑表明，存在有效的抗HIV细胞溶解性T细胞应答，其不会靶向大多数HIV感染者中的LN HIV储库。为了解决这些问题，我们将检查LN T细胞对HIV的反应，在进行性HIV感染，ART治疗的HIV感染，和精英控制HIV感染的受试者。我们的研究将为治疗操作、工程或疫苗介导的策略提供关键信息，这些策略旨在诱导HIV特异性CD 8 + T细胞能够归巢到LN的适当区域，以消除HIV储库。在目的1中，我们将确定与HIV感染的慢性进展者和精英控制者相比，抗逆转录病毒治疗对LN总的和HIV特异性CD 8+和CD 4 + T细胞的影响。在目标2中，我们将确定ART治疗的HIV感染者的LN和PBMC来源的CD 8+和CD 4 + T细胞是否具有有效的溶细胞活性。最后，在目标3中，我们将确定ART对LN CD 8+和CD 4 + HIV特异性T细胞转录调节、活化、细胞毒性特性和活化后LN保留/排出标记物的影响。

 DESCRIPTION (provided by applicant: Lymphoid tissue is the key site for the initial seeding, dissemination, and long-term maintenance of the HIV reservoir. As such, understanding those T cell properties and mechanisms required for control and elimination of HIV directly within lymphoid tissue are of critical importance to the HIV cure, eradication, and vaccine agenda. The central question underlying this proposal is whether HIV-specific CD8+ and CD4+ T cells in the lymph node (LN) have or can acquire the functional capabilities necessary to control or eliminate HIV infected cells. These studies are predicated on the concept that cytotoxic CD8+ (and CD4+) T cells are normally absent from the lymph node in HIV- subjects or those without underlying inflammatory conditions. Intuitively, this makes biological sense: why would cytotoxic T cells be wanted in a LN? Cytotoxic T cells (either CD8+ or CD4+) in the LN would function in part to eliminate antigen presenting cells, thereby dampening immune responses. However, in HIV infection, HIV vaccines, and especially HIV cure-based strategies, cytotoxic HIV- specific CD8+ T cells within the LN would be needed to control or eliminate virally infected CD4+ T cells. Our preliminary data show the presence of dysregulated perforin+ HIV-specific CD8+ T cells in the LN from chronically infected subjects, with very low expression of CXCR5, a marker required for entry into the lymphoid follicle, where HIV-infected CD4+ T cells are concentrated. Unexpectedly, antiretroviral therapy appears to reverse this, with heightened CXCR5 expression on LN CD8+ T cells, but lower levels of perforin. This is opposite of what one would want as the "kill" component of an HIV "shock and kill" cure strategy. Our findings overall indicate that LN CD8+ T cells have fundamentally different functional abilities compared to the conventional wisdom driving the HIV cure and vaccine field. These considerations suggest that were an effective anti-HIV cytolytic T cell response present, it would not target the LN HIV reservoir in the majority of HIV-infected people. To address these issues, we will examine LN T cell responses against HIV in subjects with progressive HIV infection, ART-treated HIV infection, and elite control of HIV infection. Our studies will provide critical information for therapeutic manipulation, engineering, or vaccine-mediated strategies designed to induce HIV-specific CD8+ T cells capable of homing to appropriate regions of the LN in order to eliminate HIV reservoirs. In Aim 1 we will define the effect of antiretroviral therapy on LN total and HIV-specifc CD8+ and CD4+ T cells compared to HIV infected chronic progressors and elite controllers. In Aim 2, we will determine whether LN- and PBMC-derived CD8+ and CD4+ T cells from ART-treated HIV-infected individuals have effective cytolytic activity. Finally, in Aim 3, we will determine the effect of ART on LN CD8+ and CD4+ HIV-specific T cell transcriptional regulation, activation, cytotoxic properties, and LN retention/egress markers after activation.