Dendritic Cell Restriction and Innate Immune Sensing of HIV Infection

HIV 感染的树突状细胞限制和先天免疫感应

基本信息

批准号：
8134886
负责人：
Dan Littman
金额：
$ 20.91万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-09-01 至 2012-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8134886
关键词：
Acquired Immunodeficiency Syndrome Affect Antigens Bioinformatics Bone Marrow CD4 Positive T Lymphocytes Cell Communication Cell Culture Techniques Cell Maturation Cell Surface Receptors Cell physiology Cell surface Cells Chimeric Proteins Coculture Techniques Dendritic Cells Dendritic cell activation Detection Early Diagnosis Gene Expression Profiling Genes Goals HIV HIV Infections HIV-1 HIV-2 Hand Heart Helper-Inducer T-Lymphocyte Heterophile Antigens Human IRF3 gene Immune Immune response Immune system Individual Infection Interferon Type I Investigation Maps Mediating Microbe Mus Mutation Natural Immunity Natural Resistance Nature Pathway interactions Primate Lentiviruses Production Proteins RNA Interference Resistance Resistance to infection Retroviridae Reverse Transcription Role SIV Sentinel Signal Induction Signal Pathway Signal Transduction Staging System T cell response T-Cell Activation T-Lymphocyte Transcript Transgenic Mice Vaccination Vaccine Design Vaccines Viral Viral Genome Viral Proteins Virus Virus Diseases Virus Inhibitors Virus Replication Virus-like particle antimicrobial chemokine cyclin T1 cytokine immune activation improved inhibitor/antagonist microbial microorganism monocyte mutant novel strategies pathogen prophylactic public health relevance receptor response therapeutic vaccine tool

项目摘要

DESCRIPTION (provided by applicant): Dendritic cells (DCs) have essential roles in early detection of pathogens and in subsequent activation of both innate and adaptive immune responses. The role of DCs in infection with HIV-1 remains poorly understood, even though these cells are likely to be of critical importance in developing new strategies for protective HIV vaccination. The goal of this proposal is to gain a better fundamental understanding of how HIV-1 interacts with DCs and how this interaction affects the ability of the DCs to coordinate an anti-viral immune response. Even though DCs express cell surface receptors for HIV-1 entry, they are resistant to productive viral replication due to a block that occurs before reverse transcription of the viral genome can be completed. However, DCs have a unique ability to "hand-off" the virus to CD4+ T cells, and thus greatly enhance the infectivity of these cells. HIV-1 can be coaxed into infecting DCs if the cells are first exposed to virus-like particles (VLPs) that deliver the Vpx protein of the related primate lentivirus, SIVmac. Vpx inactivates a dominant restriction for HIV-1 replication in DCs and can therefore be used to determine how the immune response is affected if HIV-1 can productively infect DCs. In preliminary studies, we have found that MDDC infected with HIV-1 (using SIVmac VLPs containing Vpx) up-regulate co-stimulatory molecules involved in the activation of T cells as well as a type I interferon response, suggesting that viral infection triggers an innate immune signaling pathway in these cells. Specific Aim 1 will be to determine how HIV-1 infection of monocyte-derived DC (MDDC) triggers innate immune signaling pathways. Gene expression profiling will be performed on MDDC to provide a bioinformatics guide for the pathways to be investigated, and RNAi approaches will then be employed to identify host cell molecules involved in induction of costimulatory molecules and other innate immunity genes. The stage of HIV-1 replication at which the host innate immune response is activated will be determined by using a combination of HIV replication inhibitors and viral mutants. Specific Aim 2 will examine the consequence of DC infection with HIV-1 on the spread of virus in cultures of DC and T cells and on anti-viral and other anti-microbial T cell responses. The spread of HIV-1 (encoding Vpr or a Vpx-Vpr fusion that permits replication in DC) and the induction of antigen-specific T cell responses will be investigated in co-cultures of MDDC and CD4+ T cells. By comparing infection under conditions that permit or restrict infection of DCs, it will be possible to determine if natural resistance of DC to infection with HIV-1 is beneficial to the host or to the virus. Together, these approaches will provide new tools for studying anti-HIV immune responses and for developing more effective vaccine strategies. PUBLIC HEALTH RELEVANCE: Understanding the nature of the immune response in the HIV-infected individual lies at the heart of our efforts to develop effective prophylactic or therapeutic vaccines for AIDS. Our proposal is to better characterize the interaction of HIV-1 with dendritic cells, which make up the early microbial detection system in the body. Results of these studies may provide new approaches for inducing strong protective immune responses against the virus.

描述（由申请人提供）：树突状细胞（DC）在病原体的早期检测以及随后的先天性和适应性免疫反应的激活中具有重要作用。 DC 在 HIV-1 感染中的作用仍然知之甚少，尽管这些细胞可能对于制定保护性 HIV 疫苗接种的新策略至关重要。该提案的目标是更好地了解 HIV-1 如何与 DC 相互作用以及这种相互作用如何影响 DC 协调抗病毒免疫反应的能力。尽管 DC 表达 HIV-1 进入的细胞表面受体，但由于病毒基因组逆转录完成之前发生的阻断，它们对有效的病毒复制具有抵抗力。然而，DC具有独特的能力，可以将病毒“传递”给CD4+T细胞，从而大大增强这些细胞的感染性。如果细胞首先暴露于传递相关灵长类慢病毒 SIVmac 的 Vpx 蛋白的病毒样颗粒 (VLP)，则 HIV-1 可以被诱导进入感染性 DC。 Vpx 使 DC 中 HIV-1 复制的主要限制失活，因此可用于确定如果 HIV-1 能够有效感染 DC，免疫反应会受到怎样的影响。在初步研究中，我们发现感染 HIV-1 的 MDDC（使用含有 Vpx 的 SIVmac VLP）上调参与 T 细胞激活的共刺激分子以及 I 型干扰素反应，这表明病毒感染引发了这些细胞中的先天免疫信号通路。具体目标 1 是确定单核细胞衍生 DC (MDDC) 的 HIV-1 感染如何触发先天免疫信号通路。将在 MDDC 上进行基因表达谱分析，为要研究的途径提供生物信息学指导，然后采用 RNAi 方法来识别参与共刺激分子和其他先天免疫基因诱导的宿主细胞分子。宿主先天免疫反应被激活的HIV-1复制阶段将通过使用HIV复制抑制剂和病毒突变体的组合来确定。具体目标 2 将检查 DC 感染 HIV-1 对 DC 和 T 细胞培养物中病毒传播以及抗病毒和其他抗微生物 T 细胞反应的影响。 HIV-1（编码允许在 DC 中复制的 Vpr 或 Vpx-Vpr 融合体）的传播和抗原特异性 T 细胞反应的诱导将在 MDDC 和 CD4+ T 细胞的共培养中进行研究。通过比较允许或限制 DC 感染的条件下的感染，将有可能确定 DC 对 HIV-1 感染的天然抵抗力是否对宿主或病毒有益。总之，这些方法将为研究抗艾滋病毒免疫反应和开发更有效的疫苗策略提供新工具。公共卫生相关性：了解艾滋病毒感染者免疫反应的本质是我们开发有效的艾滋病预防或治疗疫苗的核心。我们的建议是更好地表征 HIV-1 与树突状细胞的相互作用，树突状细胞构成了体内的早期微生物检测系统。这些研究的结果可能为诱导针对病毒的强烈保护性免疫反应提供新方法。