Mechanisms of Sexual HIV-1 Transmission

描述（由申请人提供）：自从我第一次开始照顾HIV-1 在1993年感染的病人，我印象深刻的事实是，尽管 粘膜HIV-1传播相对无效，这主要是 异性性传播的全球流行病继续有增无减， 有效的疫苗或杀微生物剂。设计的一个基本障碍是 预防策略是我们缺乏有关传播的知识 在人类生殖器粘膜中发生的事件。此K 08应用程序将支持我 奋进阐明HIV-1性传播的机制， 加强我在分子免疫学和病毒学方面的训练我察觉到 培训是实现我的长期研究目标所必需的， 翻译人类泌尿生殖免疫系统的许多方面的知识 以及它与HIV-1的相互作用转化为阻断HIV-1的策略 传输 树突状细胞（DC）和CD 4 + T细胞已被强烈牵连， 性传播过程中HIV-1的重要靶点，但直接证据 这在人类生殖器粘膜中是缺乏的。此外，机制 病毒株的选择，特别是优先传播 R5-Tropic HIV-I变体，知之甚少。我们是第一个 成功地从人类生殖器粘膜分离DC和T细胞 但我们对HIV-1辅助受体表达和体外感染性的研究 并不能解释病毒在传播过程中的选择。潜在的陷阱是 36-细胞分离所需体外迁移程序长达1小时， 这可能导致 HIV-1辅助受体表达的变化，以及无法区分 上皮内基质细胞。为了规避这些限制，我们 建立了新的程序，从阴道，外， 术后三小时内，宫颈内膜，并清楚地描绘 来源于上皮和下面的基质的细胞。具体目标 1和2，我们将研究表型和功能 浸润人类女性粘膜的T细胞和DC的性质 生殖道在目标1中，我们将比较归巢受体谱， 免疫分化和激活状态，以及抗原特异性 阴道上皮和间质中的T细胞库， 子宫颈内膜，以及循环中的T细胞。在目标2中，我们将定义阶段 的DC成熟和描绘DC谱系和分化途径， 人类生殖器粘膜。在目的3中，我们将涉及HIV-1的表达谱， 上皮内和基质白细胞上的辅助受体， 生殖器粘膜对R5-和X4-嗜性HIV-1变体的感染性。这些 研究将提高我们对人类生殖器免疫系统的认识， 女性中HIV-1靶向和毒株选择的机制 生殖道

DESCRIPTION (provided by applicant): Since I first started caring for HIV-l infected patients in 1993, I am impressed by the fact that despite the relative inefficiency of mucosal HIV-1 transmission, this mostly heterosexually transmitted global epidemic continues unabated without an effective vaccine or microbicide. One fundamental hurdle in designing prevention strategies is our lack of knowledge concerning the transmission events across the human genital mucosa. This K08 application will support my endeavor to elucidate the mechanisms of sexual HIV-l transmission while enhancing my training in molecular immunology and virology. I perceive this training as essential to accomplish my long-term research goal, which is to translate knowledge of the many facets of the human urogenital immune system and its interaction with HIV-l into strategies to interrupt HIV-l transmission. Dendritic cells (DC) and CD4+ T cells have been strongly implicated as important targets for HIV-I during sexual transmission, but direct evidence for this in the human genital mucosa is lacking. In addition, the mechanisms of viral strain selection, and particularly the preferential transmission of R5-tropic HIV-I variants, are poorly understood. We were the first to successfully isolate DC and T cells from the human genital mucosa but our studies on HIV-l coreceptor expression and in vitro infectivity did not explain viral selection during transmission. Potential pitfalls were the 36-hour long in vitroemigration procedure required for cell isolation, which may have resulted in changes of HIV-l coreceptor expression, and the inability to distinguish intraepithelial from stromal cells. To circumvent these limitations, we have established new procedures to isolate mononuclear cells from the vagina, ecto-and endocervix within three hours after surgery, and to clearly delineate cells derived from the epithelium and the underlying stroma. In Specific Aims 1 and 2 of this application, we will investigate the phenotypic and functional properties of T cells and DC infiltrating the mucosa of the human female genital tract. In Aim 1, we will compare the homing receptor profile, the state of immune differentiation and activation, and the antigen-specific repertoire of T cells among the epithelium and stroma of vagina, ecto- and endocervix, and to T cells in circulation. In Aim 2, we will define the stages of DC maturation and delineate DC lineage and differentiation pathways in the human genital mucosa. In Aim 3, we will relate the expression profile of HIV-l coreceptors on intraepithelial and stromal leukocytes isolated freshly from the genital mucosa to infectivity with R5- and X4-tropic HIV-l variants. These studies will improve our knowledge of the human genital immune system and shed light on the mechanisms of HIV-l targeting and strain selection in the female genital tract.