Suppression of the Immune Response in Spaceflight and Aging

太空飞行和衰老过程中免疫反应的抑制

• 批准号: 7945885
• 负责人: MILLIE HUGHES-FULFORD
• 金额: $ 17.03万
• 依托单位: NORTHERN CALIFORNIA INSTITUTE/RES/EDU
• 依托单位国家: 美国
• 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/7945885
• 关键词: Affect; Age; Aging; Altered Gravity; Astronauts; Bioinformatics; CD4 Positive T Lymphocytes; Candidate Disease Gene; Clinical; Collection; Contracts; Data; Depressed mood; Disease; Double-Stranded RNA; Elderly; Environment; Enzyme-Linked Immunosorbent Assay; Epithelium; Fever Chills; Force of Gravity; Gel; Gene Expression; Gene Targeting; Genes; Genetic Transcription; Goals; Head; Herpes zoster disease; Human; Humanities; Immune; Immune response; Immune system; Immunosuppression; In Vitro; Infection; Interleukin-2; International; Lymphocyte; Measures; MicroRNAs; Microarray Analysis; Microgravity; Mission; Modeling; Molecular; Ocular orbit; Older Population; Persons; Pharmacologic Substance; Phase; Production; Promoter Regions; Protein Biosynthesis; Proteins; Proteomics; Pseudomonas aeruginosa; Quantitative Reverse Transcriptase PCR; Quarantine; Regulation; Reporting; Research; Research Personnel; Signal Transduction Pathway; Simulate; Sodium Dodecyl Sulfate-PAGE; Space Flight; State of Zero Gravity; T cell response; T-Cell Activation; T-Cell Proliferation; T-Lymphocyte; Testing; Time; United States National Aeronautics and Space Administration; United States National Institutes of Health; Viral; Virus Diseases; Western Blotting; Work; age related; base; experience; immune function; in vivo; innovation; interest; novel; overexpression; pathogen; programs; public health relevance; research study; transcription factor

DESCRIPTION (provided by applicant): Project Summary. In aging, immune systems falter and the elderly are more susceptible to infection. Age related changes include decreased T-cell activation/proliferation, decreased production of IL-2 and decreased expression of IL-2R1. These are the same key immune changes that are seen in returning astronauts who have experienced altered immune function and increased vulnerability to infection during spaceflights. Loss of immune response in aging and spaceflight has been previously identified in T cells. We have previously identified microgravity induced changes in gene expression, promoter regions, transcription factors and signal transduction pathways in human CD4+ T-cells under normal and altered gravity conditions. Our preliminary data from International Space Station (ISS) described within this proposal show that in early T-cell activation at least one miRNA was upregulated during activation in normal gravity (g), while in microgravity (<g), the induction of the miRNA was muted. Moreover, three protein targets of the miRNA had increased expression in the 1.g environment suggesting a micro RNA mechanism. The changes in immune function in the elderly occur over time and are hard to evaluate. However, the same type of changes in immune response occurs microgravity, both in astronauts and in human T-cells and is easy to measure The central hypothesis is that <g regulates MiRNA in human T-cells and that weightlessness is a novel model to study the immunosuppression seen in aging. These experiments will contribute to our fundamental understanding of the molecular mechanism of immunosuppression in spaceflight and in aging. The Specific Aims are the following: (1) Identify gene expression of miRNAs during T-cell activation (using arrays and qRTPCR) under normal gravity. (2) Identify the MiRNA(s) target genes using bioinformatics and verify the changes in expression of those targets messages (qRTPCR). We will test the ability of microgravity to induce/reduce expression of MiRNAs and their targets and verify these results using miRNA overexpression viral constructs or dsRNA. (3) Analyze the protein synthesis of the upregulated/downregulated target genes (SDS PAGE gels and Western Blot proteomics) that are affected by T-cell activation under normal gravity and microgravity conditions. (4) Compare the expression of key MiRNAs candidates and genes after activation in normal gravity and microgravity, vs. that of the lymphocytes from an older population. PUBLIC HEALTH RELEVANCE: Identifying altered microRNAs and their targets in T-cells that have suppressed immune response in spaceflight but normal expression in 1g flight controls will contribute to our understanding of aging and will likely reveal important causes of immunosuppression in the elderly. In recent ISS experiments, one MiRNA is significantly downregulated in <g flown T cells when compared to onboard 1g controls; with more efficient miRNA collection, several more dysregulated MiRNAs should be identified. Because there are considerable similarities between immunosuppression in astronauts during flight and immunosuppression in the elderly, we expect that our findings will be relevant to the mission of the NIH and be broadly interesting to researchers studying molecular mechanisms of the immune response.

描述（由申请人提供）：项目摘要。 随着年龄的增长，免疫系统会衰退，老年人更容易受到感染。年龄相关的变化包括 T 细胞活化/增殖减少、IL-2 产生减少和 IL-2R1 表达减少。这些关键的免疫变化与返回宇航员身上看到的相同，他们在太空飞行期间经历了免疫功能的改变和感染风险的增加。此前已发现 T 细胞会因衰老和太空飞行而丧失免疫反应。我们之前已经发现，在正常和改变重力条件下，微重力会诱导人类 CD4+ T 细胞的基因表达、启动子区域、转录因子和信号转导途径发生变化。我们在该提案中描述的来自国际空间站 (ISS) 的初步数据表明，在早期 T 细胞激活过程中，至少一种 miRNA 在正常重力 (g) 激活过程中上调，而在微重力 (<g) 下，miRNA 的诱导作用减弱。此外，miRNA 的三个蛋白质靶标在 1.g 环境中表达增加，表明存在 micro RNA 机制。老年人免疫功能的变化是随着时间的推移而发生的，而且很难评估。然而，在微重力环境下，宇航员和人类 T 细胞都会发生相同类型的免疫反应变化，并且很容易测量。核心假设是，<g 调节人类 T 细胞中的 MiRNA，并且失重是研究衰老过程中免疫抑制的新模型。这些实验将有助于我们对太空飞行和衰老中免疫抑制的分子机制的基本理解。具体目标如下： (1) 识别正常重力下 T 细胞激活过程中 miRNA 的基因表达（使用阵列和 qRTPCR）。 (2)利用生物信息学鉴定miRNA靶基因并验证这些靶标信息表达的变化(qRTPCR)。我们将测试微重力诱导/减少 miRNA 及其靶标表达的能力，并使用 miRNA 过表达病毒构建体或 dsRNA 验证这些结果。 (3) 分析正常重力和微重力条件下受T细胞活化影响的上调/下调靶基因的蛋白质合成（SDS PAGE凝胶和Western Blot蛋白质组学）。 (4) 比较在正常重力和微重力下激活后关键 miRNA 候选者和基因的表达与来自老年人群的淋巴细胞的表达。 公共健康相关性：识别 T 细胞中改变的 microRNA 及其靶标，这些 microRNA 在太空飞行中抑制了免疫反应，但在 1g 飞行对照中表达正常，这将有助于我们对衰老的理解，并可能揭示老年人免疫抑制的重要原因。在最近的 ISS 实验中，与机上 1g 对照相比，<g 飞行 T 细胞中的一种 miRNA 显着下调；通过更有效的 miRNA 收集，应该鉴定出更多失调的 miRNA。由于宇航员在飞行期间的免疫抑制与老年人的免疫抑制之间存在相当大的相似性，因此我们预计我们的研究结果将与 NIH 的使命相关，并引起研究免疫反应分子机制的研究人员的广泛兴趣。