Toll-Like Receptors in Bacterial Antigen Induced HIV-LTR

在HIV感染患者中，血浆HIV载量增加伴随机会性感染，包括分枝杆菌和衣原体感染，表明细胞活化和活跃的病毒复制。 先天免疫系统和Toll样受体（TLR）在机会性感染期间HIV复制中的作用尚不清楚。 我已经证明LPS通过IL-1 R信号分子通过先天免疫系统受体TLR 4激活HIV长末端重复序列（LTR）。在初步实验中，我观察到TLR 2转导分枝杆菌抗原可溶性结核因子（STF）应答以激活HIV-LTR，并且TLR 4（LPS）和TLR 2（STF）配体诱导HIV-LTR的协同激活。 参与TLR 2介导的STF激活HIV-LTR的分子机制以及在TLR 2和TLR 4配体之间观察到的HIV-LTR反式激活的协同作用机制尚不清楚。 此外，尚不清楚衣原体效应分子热休克蛋白60（cHSP 60）是否被TLR 4或TLR 2识别。 本提案的总体目标是确定先天免疫受体TLR的作用，以及参与分枝杆菌和衣原体抗原诱导的HIV-1-LTR活化和复制的分子信号传导机制，以及参与TLR 2和TLR 4配体协同活化HIV-LTR的分子机制。假设：我推测，通过TLRs（TLR 2为STF，TLR 4为LPS和cHSP 60）激活先天免疫系统介导了细菌和分枝杆菌抗原诱导的NF-κ B和HIV-LTR通过IL-1 R信号分子的激活。 我还假设TLR 4和TLR 2配体协同诱导HIV-LTR反式激活。 因此，TLR可能提供机会性感染（如结核分枝杆菌和衣原体感染）与HIV复制增加之间的潜在分子联系。具体目标是：（1）-评估TLR 2和TLR 4的作用，并确定TLRs在可溶性结核因子（STF）和衣原体HSP 60（cHSP 60）诱导的巨噬细胞中HIV-LTR活化中的功能合作和协同作用。（2）探讨TLR 20和TLR 4介导HIV-LTR反式激活和HIV复制的分子信号转导机制。（2a）-为了确定IL-1信号传导分子Tollip、MyD 88和NF-κ B活化在TLR 2介导的HIV-LTR活化中的作用。（2b）研究PI 3激酶、Rac 1和Akt在TLR 2和TLR 4诱导的HIV- LTR激活和HIV复制中的作用。（2c）探讨TLR 2和TLR 4配体协同激活HIV-LTR的分子机制。重要性：对先天性免疫受体（如TLR）的作用以及微生物抗原诱导的HIV-LTR反式激活和HIV复制中涉及的分子信号传导机制的进一步了解，可能为更好地控制分枝杆菌和衣原体感染期间的HIV复制提供新的靶点。

In HIV infected patients, plasma HIV load increases with concomitant opportunistic infections, including Mycobacterial and Chlamydial infections suggesting cell activation and active virus replication. The role of the innate immune system and Toll-like Receptors (TLRs) in HIV replication during opportunistic infections are unknown. I have shown that LPS activates HIV-long terminal repeat (LTR) through innate immune system receptor TLR4 via IL-1R signaling molecules. In preliminary experiments, I observed that TLR2 transduces mycobacterial antigen Soluble Tuberculosis Factor (STF) response to activate HIV-LTR, and that TLR4 (LPS) and TLR2 (STF) ligands induce synergistic activation of HIV-LTR. The molecular mechanisms involved in TLR2-mediated STF activation of HIV-LTR and the mechanisms of the synergy observed between TLR2 and TLR4 ligands for HIV-LTR transactivation are unknown. Furthermore, it is unknown whether Chlamydial effector molecule, Heat Shock Protein 60 (cHSP60) is recognized by TLR4 or TLR2. The overall goals of this proposal are to determine the role of the innate immune receptors, TLRs, and the molecular signaling mechanisms involved in mycobacterial and chlamydial antigen-induced HIV-1-LTR activation and replication, as well as the molecular mechanisms involved in the synergistic activation of HIV-LTR by TLR2 and TLR4 ligands. The hypothesis: I hypothesize that activation of the innate immune system through TLRs (TLR2 for STF, and TLR4 for LPS and cHSP60) mediate the bacterial and mycobacterial antigen-induced activation of NF-kB and HIV-LTR via IL-1R signaling molecules. I also hypothesize that TLR4 and TLR2 ligands synergistically induce HIV- LTR transactivation. Thus, TLRs may provide a potential molecular link between opportunistic infections such as Mycobacterial tuberculosis and Chlamydial infections and increased HIV replication. The specific aims are: (1)-To assess the role of TLR2 and TLR4, and to determine the functional cooperation and synergy of TLRs in Soluble Tuberculosis Factor (STF)-, and chlamydia HSP60 (cHSP60)-induced HIV-LTR activation in macrophages. (2)-To investigate the molecular signaling mechanisms involved in TLR20 and TLR4-induced HIV-LTR transactivation and HIV replication. (2a)-To determine the role of the IL-1 signaling molecules, Tollip, MyD88 and NF-kB activation in TLR2-mediated HIV-LTR activation. (2b)-To study the role of PI3 Kinase, Rac1 and Akt in TLR 2 and TLR4-induced activation of HIV- LTR and HIV replication. (2c)-To investigate the molecular mechanism of the synergy between TLR2 and TLR4 ligands forHIV-LTR activation. Significance: Improved understanding of the role of innate immune receptors, such as TLRs and the molecular signaling mechanisms involved in microbial antigen induced HIV-LTR transactivation and HIV replication may provide new targets to better control HIV replication during mycobacterial and chlamydial infections.