miR-155 regulation of cellular susceptibility to HIV-1 infection

miR-155对细胞对HIV-1感染易感性的调节

• 批准号: 8517576
• 负责人: Julio Martin-Garcia
• 金额: $ 18.15万
• 依托单位: DREXEL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8517576
• 关键词: Anti-Retroviral Agents; Binding; Biological Assay; CCR5 gene; CD4 Positive T Lymphocytes; Cell Line; Cell physiology; Cells; Computer Simulation; Dendritic Cells; Dependency; Development; Disease Progression; Environment; Figs - dietary; Functional RNA; Gene Expression; Generations; Glycoproteins; HIV; HIV-1; Human; Imiquimod; Immune response; Immune system; Importins; Infection; Inflammatory; Inflammatory Response; Interferon Type I; Life Cycle Stages; Ligands; Light; Malignant Neoplasms; Mediating; Messenger RNA; MicroRNAs; Molecular Profiling; Natural Immunity; Nuclear Pore Complex Proteins; Oligonucleotides; Patients; Plasmids; Play; Poly I-C; Predisposition; Prevention; Production; Regulation; Regulator Genes; Reporter; Research; Resistance; Role; Surface; System; TLR3 gene; TLR4 gene; TLR7 gene; Toll-like receptors; Transcript; Up-Regulation; Validation; Vesicular stomatitis Indiana virus; Viral; Virus; Virus Diseases; adaptive immunity; beta-Chemokines; cell growth regulation; cell type; chemokine; cytokine; immune activation; innovation; insight; mRNA Expression; mRNA Transcript Degradation; macrophage; monocyte; novel; pathogen; receptor; research study; response; transmission process

DESCRIPTION (provided by applicant): Macrophages and dendritic cells (DCs) play key roles in HIV-1 infection and in innate immunity, but the role of innate immunity, and in particular TLRs, in HIV-1 infection and disease progression is poorly understood. LPS and poly(I:C) (TLR4 and TLR3 ligands, respectively), have been shown to inhibit HIV-1 replication in and infection of macrophages, albeit the mechanisms are unclear. We have found that stimulation of human monocyte-derived macrophages (MDMs) through TLR3 and 4, but not through TLR7 and 9, abrogates their susceptibility to HIV-1 infection. TLR3-mediated suppression of infection was also observed in monocyte derived DCs (moDCs). Subsequent studies in MDMs showed no change in surface expression of CD4 and CCR5 between TLR3/4 and TLR7/9-stimulated cells, similar production of type I interferons, pro-inflammatory cytokines and beta-chemokines, and the same effect on susceptibility to infection in stimulated cells exposed to vesicular stomatitis virus glycoprotein (VSV-G)-pseudotyped virus. MicroRNAs (miRNAs) are potent regulators of gene expression, playing pivotal roles in development, differentiation and in the regulation of immune and inflammatory responses. It has been shown that TLR stimulation can modulate miRNA expression, and some miRNAs seem to be involved in the modulation of susceptibility to HIV-1 infection in primary cells. In this sense, we have found that TLR3-, 4- and 7-stimulated MDMs display overlapping but distinct changes in miRNA expression profiles, and we have identified a subset of four miRNAs that are up-regulated in cells stimulated through TLR3 and 4 but not through TLR7. Among them, miR-155 showed the highest and more consistent up-regulation, and we have since confirmed its specific up-regulation in TLR3/4-stimulated MDMs and in TLR3-stimulated moDCs from multiple donors. In addition, pre-treatment of poly(I:C)-stimulated MDMs with an anti-miR-155 antagomir inhibited miR-155 induction and increased their susceptibility to HIV-1 infection. Moreover, miR-155 over-expression in MDMs and cell lines led to suppression or reduction of HIV-1 infection. Target analysis has suggested that several confirmed or potential HIV-dependency factors (HDFs: several importins and nucleoporins, and LEDGF, among others), are predicted targets for miR-155, and reduced mRNA levels in selected potential targets have been observed. Thus, we hypothesize that miR-155 has the capacity to reduce susceptibility to HIV-1 infection by decreasing the levels of one or more HDFs, leading to an intracellular environment that is less conducive to productive HIV-1 infection. Our specific aims are: (i) To identify and validate mRNA targets for miR-155 that could participate in the modulation of susceptibility to HIV-1 infection in macrophages and dendritic cells; and (ii) To define the mechanism(s) by which modulation of miR-155 levels leads to altered susceptibility to HIV-1 infection in MDMs and moDCs. These novel studies will shed light on our limited understanding of the interplay between miRNAs and HIV-1, and might open new avenues to explore the use of miR-155 to decrease susceptibility to HIV-1 infection.

描述（由申请人提供）：巨噬细胞和树突状细胞（DC）在HIV-1感染和先天免疫中起关键作用，但先天免疫的作用，尤其是TLR，尤其是TLR 在HIV-1中，感染和疾病进展知之甚少。 LPS和POLY（I：C）（分别分别是TLR4和TLR3配体）已显示抑制巨噬细胞中HIV-1复制和感染的HIV-1复制，尽管该机制尚不清楚。我们发现，通过TLR3和4的刺激人类单核细胞衍生的巨噬细胞（MDM），但不是通过TLR7和9刺激其对HIV-1感染的敏感性。在单核细胞衍生的DC（MODC）中，还观察到TLR3介导的感染抑制。随后在MDMS中进行的研究表明，TLR3/4和TLR7/9刺激的细胞之间CD4和CCR5的表面表达没有变化，I型干扰素的相似产生，促炎性细胞因子和β化学因子以及对刺激细胞易感性的影响相同 病毒糖蛋白（VSV-G）假性型病毒。 microRNA（miRNA）是基因表达的有效调节剂，在发育，分化以及免疫和炎症反应的调节中起关键作用。已经表明，TLR刺激可以调节miRNA表达，并且一些miRNA似乎参与了原代细胞中HIV-1感染的易感性的调节。从这个意义上讲，我们发现TLR3-，4和7刺激的MDM显示出重叠但miRNA表达谱的不同变化，并且我们已经确定了四个miRNA的子集，这些miRNA在通过TLR3和4刺激的细胞中上调，但没有通过TLR7刺激。其中，miR-155显示出最高和更一致的上调，此后我们已经确认了其在TLR3/4刺激的MDMS中的特定上调，并且在TLR3刺激了来自多个供体的MODC中。此外，使用抗MIR-155 Antagomir的Poly（I：C）刺激的MDM的预处理抑制了miR-155的诱导，并增加了其对HIV-1感染的敏感性。此外，MIR-155在MDM和细胞系中的过表达导致HIV-1感染的抑制或还原。目标分析表明，一些确认或潜在的HIV依赖性因子（HDF：几种进口蛋白和核孔蛋白，LEDGF等）是miR-155的靶标，并且已经观察到选定潜在靶标的mRNA水平降低。因此，我们假设miR-155通过降低一个或多个HDF的水平来降低对HIV-1感染的敏感性，从而导致细胞内环境不利于生产性HIV-1感染。我们的具体目的是：（i）识别和验证可能参与巨噬细胞和树突状细胞中HIV-1感染易感性的miR-155的mRNA靶标； （ii）定义MIR-155水平调节导致MDMS和MODC中HIV-1感染的易感性改变的机制。 这些新颖的研究将阐明我们对miRNA和HIV-1之间相互作用的有限理解，并可能开辟了新的途径，以探索miR-155的使用以降低对HIV-1感染的易感性。