Exploration of novel pan-HPV treatments to block development of AIDS-associated c

描述（由申请人提供）：持续的高风险人乳头瘤病毒（HPV）感染是HIV阳性个体发生肛门生殖器癌的重要原因。本研究的长期目标是了解HPV如何与与HIV相同的宿主受体之一相互作用，并通过激活粘膜表面的先天免疫来寻找治疗HPV感染和相关疾病的新方法。分泌性白细胞蛋白酶抑制剂（SLPI）是一种在生殖道粘膜液中发现的丝氨酸蛋白酶抑制剂，已被证明通过阻断HIV与膜联蛋白A2 （ANXA2）的相互作用来抑制HIV对巨噬细胞的感染。HPV逃避免疫的机制之一是在没有Langerhans细胞（HPV和HIV感染部位的抗原呈递细胞）共同刺激的情况下通过抗原呈递诱导耐受。我们未发表的数据表明，HPV的L2衣壳蛋白可能通过与LC上的ANXA2相互作用介导免疫逃逸，从而抑制LC的成熟。LC也是HIV的初始细胞靶点，在病毒传播中起着关键作用。因此，我们将在本提案中探讨LC中HIV、HPV、ANXA2和SLPI之间的关系。我们发表的数据表明，可以用toll样受体（TLR）激动剂激活hpv暴露的LC。然而，目前尚不清楚TLR激动剂是否足以克服HPV和HIV合并感染个体暴露于HPV的LC的抑制作用。我们假设1)为了逃避T细胞免疫，HPV16 L2通过与细胞表面受体ANXA2的相互作用抑制LC的成熟，2)TLR激动剂治疗会增加SLPI的产生，同时诱导HPV暴露的LC激活HPV/HIV合并感染患者的HPV特异性T细胞。目的1)确定HPV16 L2是否通过与ANXA2的相互作用抑制LC的成熟，并评估SLPI是否可以阻断LC对HPV和HIV的摄取；目的2)探讨TLR激动剂是否上调LC产生SLPI，诱导暴露于HPV16的LC激活HPV感染或HPV/HIV合并感染患者的HPV16特异性T细胞；3)确定除HPV16外，其他致癌型HPV是否也能抑制LC成熟，以及TLR激动剂治疗LC是否能逆转其他高危HPV基因型在hiv感染者中致癌的免疫逃逸。这些目标将通过在LC中进行共免疫沉淀和敲除研究来确定HPV受体来实现。将使用免疫调节化合物来测试免疫抑制的逆转，并通过分析LC表型和功能来评估其他HPV基因型的免疫抑制能力。这种机制研究可能导致鉴定新的免疫调节剂，目的是清除HIV感染者体内持续的HPV感染，从而降低发生更严重疾病的风险，如宫颈癌、肛门癌和其他HPV相关癌症。

DESCRIPTION (provided by applicant): Persistent high risk human papillomavirus (HPV) infection is a significant cause of anogenital cancers in HIV- positive individuals. The long-term goal of this study is to understand how HPV interacts with one of the same host receptors as HIV and to find new ways to treat HPV infection and associated diseases by activating innate immunity at mucosal surfaces. Secretory leukocyte protease inhibitor (SLPI) is a serine protease inhibitor found in mucosal fluids of the genital tract and has been shown to inhibit infection of macrophages by HIV by blocking the interaction of HIV with annexin A2 (ANXA2). One of the mechanisms by which HPV escapes immunity is inducing tolerance via antigen presentation in the absence of co-stimulation by Langerhans cells (LC), the antigen-presenting cells at the site of HPV and HIV infection. Our unpublished data suggest that the L2 capsid protein of HPV may mediate immune escape by interacting with ANXA2 on LC, thereby suppressing the maturation of LC. LC are also the initial cellular targets of HIV and play a critical role in viral dissemination. Therefore we will explore the relationship between HIV, HPV, ANXA2, and SLPI in LC in this proposal. Our published data show that it is possible to activate HPV-exposed LC with Toll-like receptor (TLR) agonists. However, it is unknown whether TLR agonists will be potent enough to overcome the suppressive effects of HPV-exposed LC from HPV and HIV co-infected individuals. We hypothesize that 1) to escape T cell immunity, HPV16 L2 suppresses the maturation of LC through interaction with the cell surface receptor ANXA2, and 2) that treatment with TLR agonists will increase SLPI production and simultaneously induce HPV-exposed LC to activate HPV-specific T-cells from HPV/HIV co-infected patients. The following aims will be explored: Aim 1) Determine whether HPV16 L2 is responsible for suppressing the maturation of LC through interaction with ANXA2 and assess whether SLPI can block uptake of HPV and HIV by LC; Aim 2) Investigate whether TLR agonists up-regulate SLPI production by LC and induce HPV16- exposed LC to activate HPV16-specific T cells from patients infected with HPV or co-infected with HPV/HIV; and Aim 3) Determine whether apart from HPV16, other oncogenic HPV types also suppress LC maturation, and whether treatment of LC with TLR agonists reverses the immune escape of other high risk HPV genotypes that can cause cancer in HIV-infected individuals. These aims will be accomplished by performing co- immunoprecipitations and knock-down studies in LC to identify the HPV receptor. Reversal of immune suppression will be tested using immune-modulating compounds and immunosuppressive capacity of other HPV genotypes will be assessed by analyzing LC phenotype and function. This mechanistic research could lead to the identification of novel immune modulators with the goal of clearing persistent HPV infection in HIV- infected individuals and therefore reducing risk of developing more serious disease such as cervical, anal and other HPV-associated cancers. PUBLIC HEALTH RELEVANCE: Human papillomavirus (HPV) causes an increased incidence of several different types of cancer in HIV- infected individuals because of their immune suppression. With increased life expectancies due to advances in AIDS therapies and with high incidence of HPV co-infection, there is an urgent need to develop therapeutic strategies to reduce the risk and prevent the development of HPV-associated malignancies. Successful completion of this project will lead to a greater understanding of how HIV and HPV might co-interact with immune cells and the development of strategies to expedite HPV viral clearance in HIV-infected people by activating local innate immunity.