Matrix remodeling in the lung during HIV infection

描述（由申请方提供）：肺是HIV的重要储存库和HIV复制的场所，可导致病毒诱导的肺损伤。艾滋病毒如何导致直接肺损伤，以及病毒如何在肺内持续复制，目前尚不清楚。我们发现，HIV感染的淋巴细胞诱导成纤维细胞分泌纤连蛋白（FN），通过阐述TGF β 1，从而有助于基质重塑。我们还表明，基质FN和FN的蛋白水解片段，III 1-C，增强HIV感染的淋巴细胞和FN结合的HIV保持感染性的时间比未结合的病毒。我们假设细胞外基质，特别是纤连蛋白，增强了肺内的HIV感染，相反，肺内的HIV增加了蛋白水解活性，导致炎症和纤维化。为了测试这一点，我们将：1。确定基质FN如何增加HIV的感染性和稳定性。基质纤维连接蛋白和肺泡巨噬细胞的相互作用可能有助于在肺中持续的病毒储库。2.定义HIV感染细胞的基质降解特性。我们假设HIV感染改变了净蛋白酶活性，从而导致基质降解和生物活性蛋白水解片段的产生。3.测定HIV感染和HAART对支气管肺泡灌洗液（BALF）蛋白酶活性的影响。HIV诱导的蛋白酶活性可能通过产生增强感染的纤连蛋白蛋白的蛋白水解片段、切割HIV感染的天然抑制剂（如SDF-1 α）或产生直接引起肺损伤的蛋白水解片段，从而导致持续性感染和肺损伤。因此，我们将测量HAART前后HIV患者BALF样本的蛋白水解活性。4.通过使用蛋白质组学中的新方法鉴定BALF蛋白质随时间的表达模式，开发肺中HIV和HAART的“蛋白质时间轴”。蛋白质组学分析还可以识别HIV诱导的肺部疾病的新生物标志物，并揭示HIV诱导的肺部疾病中的未知途径。这些实验将增加我们对肺中HIV感染的非感染性并发症的理解，例如涉及基质重塑的肺气肿，并提供对空域环境中HIV诱导的蛋白水解的后果的深入了解。

DESCRIPTION (provided by applicant): The lung is an important reservoir of HIV and site of HIV replication, which results in virus-induced lung injury. How HIV leads to direct lung injury, and how virus replication is sustained within the lung, are not known. We found that HIV-infected lymphocytes induced fibroblasts to secrete fibronectin (FN), by elaboration of TGFbeta1, thus contributing to matrix remodeling. We also showed that matrix FN and a proteolytic fragment of FN,III1-C, enhanced HIV infection of lymphocytes and that FN-bound HIV remained infectious longer than unbound virus. We hypothesize that extracellular matrix, specifically fibronectin, enhances HIV infection within the lung and, conversely, that HIV within the lung increases proteolytic activity that contributes to inflammation and fibrosis. To test this we will: 1. Determine how matrix FN increases infectivity and stability of HIV. Interactions of matrix fibronectin and alveolar macrophages may contribute to persistent viral reservoir in the lung. 2. Define the matrix-degrading properties of HIV-infected cells. We hypothesize that HIV infection alters net protease activity, which results in matrix degradation and generation of biological active proteolytic fragments. 3. Determine the effect of HIV infection and HAART on protease activity of bronchoalveolar lavage fluid (BALF). HIV-induced protease activity may contribute to persistent infection and lung injury by generating proteolytic fragments of fibronectin that enhance infection, by cleaving natural inhibitors of HIV infection such as SDF-1alpha or by generating proteolytic fragments that directly cause lung injury. Therefore, we will measure proteolytic activity in BALF samples from HIV patients before and following HAART. 4. Develop a "protein timeline" of HIV and HAART in the lung by identifying patterns of BALF protein expression over time using new methodologies in proteomics. Proteomic analysis may also identify new biomarkers of HIV-induced lung disease and reveal unsuspected pathways in HIV induced lung disease. These experiments will increase our understanding of the non-infectious complications of HIV infection in the lung, such as emphysema that involves matrix remodeling, and provide insight into consequences of HIV-induced proteolysis in the airspace environment.