Restoration of alveolar macrophage function in HIV patients: A clinical study.

描述(申请人提供)：HIV以淋巴细胞和巨噬细胞为宿主细胞。大多数研究将艾滋病的进展仅仅等同于T细胞监测的丧失。然而，有人认为，由于艾滋病毒寄生于巨噬细胞，该病毒可能会直接损害吞噬细胞的杀菌能力。通过探索吞噬小体成熟的新方法，我们已经证明，HIV感染降低了吞噬小体的水解力，并损害了超氧化物的产生。鉴于巨噬细胞作为抵御微生物入侵的主要屏障的作用，这将产生严重的后果，特别是在呼吸道等粘膜表面。在这项研究中，我们建议解决以下三个问题。 1.艾滋病毒感染在多大程度上损害巨噬细胞的抗微生物能力？HIV感染的PBMC来源的巨噬细胞将接受一组生理测试，以确定吞噬细胞功能受损的程度，即吞噬小体酸化、溶酶体水解酶的获得、活性氧和氮中间体的产生，以及HIV感染细胞限制一组模式细菌病原体生长的能力。 2.HIV感染者的肺泡巨噬细胞是否表现出类似的吞噬功能颠覆？在体外验证之后，将对马拉维伊丽莎白女王医院的艾滋病毒感染患者的支气管腔细胞重复进行这些分析。此外，还将采集样本进行电子显微镜和免疫电子显微镜检查，并提取总核酸，以便对可能的联合感染进行回顾性鉴定。 3.艾滋病毒如何损害巨噬细胞的功能，这种损害能否通过化疗逆转？ 我们建议进行功能研究，以确定HIV如何调节吞噬小体的杀菌能力。 B.我们将进行高通量筛查，以确定能抵消艾滋病毒抑制活动的小分子。 我们将测试这些化合物逆转HIV感染患者肺泡巨噬细胞吞噬功能抑制的能力。

DESCRIPTION (provided by applicant): HIV targets both lymphocytes and macrophages as host cells. Most studies equate progression to AIDS solely as the loss of T cell surveillance. However, it has been suggested that because HIV parasitizes macrophages, the virus could impair the microbicidal capacity of the phagocyte directly. Exploiting novel assays for phagosomal maturation we have demonstrated that HIV infection diminishes the hydrolytic capacity of the phagosome and impairs superoxide production. Given the macrophage's role as the primary barrier against microbial invasion this will have serious consequences, particularly at mucosal surfaces such as the respiratory tract. In this study we propose to address the following 3 questions. 1. To what extent does HIV infection compromise the anti-microbial capacity of macrophages? HIV-infected, PBMC-derived macrophages will be subjected to a panel of physiological assays to determine the extent to which phagocyte function is impaired i.e. phagosome acidification, the acquisition of lysosomal hydrolases, the generation of reactive oxygen and nitrogen intermediates, and the capacity of the HIV-infected cells to limit growth of a panel of model bacterial pathogens. 2. Do alveolar macrophages from HIV-infected patients demonstrate similar subversion of phagocyte function? Following in vitro validation, these assays will be repeated on broncholavage cells from HIV-infected patients at the Queen Elizabeth Hospital in Malawi. In addition, samples will be acquired for electron microscopy and for immuno-electron microscopy, and total nucleic acid will be extracted for retrospective identification of possible co-infections. 3. How does HIV impair macrophage function and can this be reversed chemotherapeutically? a. We propose functional studies to determine how HIV modulates the microbicidal capacity of the phagosome. b. We will conduct high-throughput screens to identify small molecules that counteract the suppressive activity of HIV. c. We will assay these compounds for their ability to reverse the suppression of phagocyte function in alveolar macrophages from HIV-infected patients.