FUNCTIONAL STUDIES OF HIV-TAT EFFECTS ON ENDOTHELIUM

描述（根据申请人的描述改编） HIV-1达特蛋白由感染的T细胞分泌， 单核巨噬细胞，先前的研究表明，它可以有效地改变 内皮生长、迁移和粘附相互作用。 功能 达特对内皮细胞的作用似乎是通过其特异性结合 血管内皮生长因子（VEGF）的Flk-1/KDR受体， α 5 β 1、α V β 3和α V β 5表面整联蛋白。 这 研究小组最近发现，达特可以激活FLT 4受体， VEGF-C/VRP，以及几个Src激酶家族成员，蛋白质 酪氨酸磷酸酶SHPTP-2、粘着斑激酶FAK和RAFTK/Pyk 2 以及p44/42 MAP激酶Erk 1和2。 此外，达特治疗人类 脐静脉内皮细胞（HUVEC）或骨髓内皮细胞 （BMEC）导致一氧化氮（NO）的释放，增加蛋白质 内皮型一氧化氮合酶（eNOS）水平，以及 β-趋化因子单核细胞趋化蛋白（MCP-1）。 NO是一个重要的 VEGF对血管细胞生长、趋化性和 磁导率 MCP-1有助于单核细胞-巨噬细胞的募集， T细胞，并被认为介导T细胞穿过淋巴细胞的迁移。 内皮单层 对达特的观察，加上以前的 报告的工作，表明它可以破坏几个重要的内皮细胞， 通过共同选择表面VEGF和整合素受体触发信号发挥作用 转导途径。 该建议旨在系统地描述信号通路 在HUVEC和BMEC中使用达特，并将其与由 VEGF-A和VEGF-C/VRP，以确定TAT介导的细胞凋亡的机制。 有丝分裂、趋化性、粘附分子表达以及NO和MCP-1 release. 从这些研究中获得的信息应该有助于 定义HIV-1如何引起内皮功能障碍和损伤，并帮助 创造新的治疗方法来保护HIV感染的宿主。

DESCRIPTION (Adapted from the applicant's description) The HIV-1 TAT protein is secreted from infected T-cells and monocyte-macrophages, and prior studies suggest it can potently alter endothelial growth, migration and adhesive interactions. The functional effects of TAT on endothelium appear to occur via its specific binding to the Flk-1/KDR receptor for vascular endothelial growth factor (VEGF) and to the alpha5 beta1, alphav beta3 and alphav beta5 surface integrins. This group recently have found that TAT can activate the FLT4 receptor for VEGF-C/VRP, as well as several Src kinase family members, the protein tyrosing phosphatase SHPTP-2, the focal adhesion kinases FAK and RAFTK/Pyk2 and the p44/42 MAP kinases Erk1 and 2. Moreover, TAT treatment of human umbilical vein endothelium cells (HUVEC) or bone marrow endothelium cells (BMEC) resulted in the release of nitric oxide (NO), increased protein levels of endothelial nitric oxide synthase (eNOS), and generation of the beta-chemokine monocyte chemotactic protein (MCP-1). NO is an important mediator of VEGF effects on vascular cell growth, chemotaxis and permeability. MCP-1 contributes to recruitment of monocyte-macrophages and T-cells and is believed to mediate transmigration of T-cells across an endothelial monolayer. The observations on TAT, coupled with previously reported work, suggest that it can subvert several vital endothelial functions by co-opting surface VEGF and integrin receptor triggered signal transduction pathways. This proposal seeks to systematically characterize the signaling pathways utilized by TAT in HUVEC and BMEC, and contrast them with those triggered by VEGF-A and VEGF-C/VRP, in order to determine the mechanisms of TAT-mediated mitogenesis, chemotaxis, adhesion molecule expression, and NO and MCP-1 release. The information obtained from these studies should help in defining how HIV-1 may cause endothelial dysfunction and injury, and assist in the creation of novel therapeutics to protect the HIV infected host.