Impact of Chemotherapy and Stem Cell Transplant on HIV-1 Reservoir Dynamics

描述（由申请人提供）：尽管抗逆转录病毒治疗长期抑制循环病毒，但HIV-1储存库仍以潜伏形式存在。实现治愈HIV-1感染的主要挑战是这些潜伏病毒库的持久性。迄今为止，只有一名接受清髓异基因造血干细胞移植治疗急性髓系白血病的患者获得了HIV-1感染的功能性“治愈”，供体细胞缺乏功能性CCR5， CCR5是HIV-1进入宿主细胞的共同受体。移植前细胞毒性化疗减少HIV-1储存库可能有助于病毒根除；然而，细胞毒性化疗合并或不合并造血干细胞移植（HSCT）对病毒库和宿主因子以及免疫反应的影响在很大程度上是未知的。我们的研究将对HIV-1的持久性和进化提供更深入的了解，这将对旨在消除HIV储存库的治疗方法具有实际意义。我们建议研究细胞毒性化疗和/或造血干细胞移植对HIV-1感染的血液系统恶性肿瘤患者启动全身抗肿瘤治疗的病毒库大小、进化和免疫功能的影响。我们假设细胞毒性化疗或HSCT减少了潜伏感染的细胞池，并将表现为总和综合HIV-1 DNA数量的长期减少。我们还假设，在细胞减少治疗后的免疫重建过程中没有显著的进化，但HIV-1 DNA的减少和随后CD4+淋巴细胞亚群和其他组织区室的再扩增可能导致剩余病毒库多样性的变化。本研究的具体目标包括：1)研究恶性血液病化疗或造血干细胞移植对外周血和骨髓库大小的影响；2)研究化疗前后残留病毒血症、淋巴细胞活化和hiv特异性免疫反应的变化；3)研究细胞毒性化疗对HIV-1进化、组织区隔化和库多样性的影响。这项为期五年的研究将利用创新的方法来研究宿主动态，如454深度测序和分析，以检测和量化来自宿主组织和血浆病毒血症的低水平HIV-1 DNA，低于标准测试的检测极限。与免疫学家和进化病毒学家合作，淋巴细胞活化、宿主进入因子和艾滋病毒特异性免疫的测量也将纳入研究计划。该候选人目前是哈佛医学院布里格姆妇女医院（BWH）传染病科的医学讲师，并计划进一步培训，将在转化病毒学和面向患者的研究方面成为独立的学术生涯。该项目将在BWH的Daniel Kuritzkes博士和Manish Sagar博士的指导下进行。

DESCRIPTION (provided by applicant): HIV-1 reservoirs continue to exist in latent form despite long-term suppression of circulating virus with antiretroviral therapy. The main challenge in achieving a cure for HIV-1 infection is the persistence of these latent viral reservoirs. To dat, there has only been one functional "cure" of HIV-1 infection in an individual who underwent myeloablative allogeneic hematopoietic stem cell transplant for acute myeloid leukemia with donor cells lacking functional CCR5, a co-receptor used by HIV-1 to enter host cells. Reduction of HIV-1 reservoirs with pre-transplant cytotoxic chemotherapy likely contributed to viral eradication; however, the effects of cytotoxic chemotherapy with or without hematopoietic stem cell transplant (HSCT) on the viral reservoir and host factors and immune responses are largely unknown. Our study will provide greater insight into the persistence and evolution of HIV-1 that will have practical implications for therapeutics aimed at eliminating HIV reservoirs. We propose to investigate the effect of cytotoxic chemotherapy and/or HSCT on viral reservoir size, evolution, and immune function in HIV-1 infected individuals with hematologic malignancies initiating systemic anti-neoplastic therapy. We hypothesize that cytotoxic chemotherapy or HSCT reduces pools of latently infected cells, and will be manifested as a long-term reduction in the amount of total and integrated HIV-1 DNA. We also hypothesize that there is no significant evolution during immune reconstitution following cytoreductive therapy, but reductions in HIV-1 DNA and subsequent re-expansion of CD4+ lymphocyte subsets and other tissue compartments may lead to changes in the diversity of the remaining viral reservoir. Specific aims of this proposal include: 1) investigate the effects of chemotherapy or HSCT for hematologic malignancy on peripheral blood and bone marrow reservoir size, 2) study the changes in residual viremia, lymphocyte activation, and HIV-specific immune responses before and after chemotherapy, and, 3) investigate the effects of cytotoxic chemotherapy on HIV-1 evolution, tissue compartmentalization, and reservoir diversity. This five-year study will utilize innovative approaches to investigate reservoir dynamics such as 454 deep sequencing and assays to detect and quantify low levels of HIV-1 DNA from host tissue and plasma viremia below the limit of detection of standard tests. Measures of lymphocyte activation, host-entry factors and HIV-specific immunity will also be integrated into the research plan in collaboration with immunologists and evolutionary virologists. The candidate is currently an Instructor of Medicine at Harvard Medical School in the Division of Infectious Diseases at the Brigham and Women's Hospital (BWH), and plans on further training that will lead to an independent academic career in translational virology and patient-oriented research. This project will be conducted under the mentorship of Dr. Daniel Kuritzkes and Dr. Manish Sagar at the BWH.