Molecular study of mouse viral resistance mechanisms

小鼠病毒抵抗机制的分子研究

• 批准号: 7033290
• 负责人: Michael G Brown
• 金额: $ 37.3万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7033290
• 关键词: Betaherpesvirinae; biological signal transduction; genetic regulation; genetically modified animals; host organism interaction; immunogenetics; laboratory mouse; microorganism immunology; natural killer cells

DESCRIPTION (provided by applicant): NK cells are well known for the capacity to recognize and lyse virus infected cells. Indeed, host defenses in humans and mice that lack NK cell immunity are quite vulnerable to overwhelming and recurrent Herpes virus infections. In C57BL/6 mice, host anti-murine cytomegalovirus (MCMV) immunity requires NK cell expressed Ly49H activation receptor recognition of its virus encoded m157 ligand on MCMV infected cells. We recently showed that NK cells in NZW mice however, control experimental MCMV infection without a role for Ly49H+ NK cells. Herein we have extended our finding in MA/My mice. The MA/My strain is noteworthy since it also displays very effective NK cell-mediated control of MCMV infection, but NK cells in this strain do not express Ly49H receptors. Interestingly, MCMV resistance in MA/My is strongly associated with MHC and also non MHC genes. Thus, we have found that NK cells utilize multiple antiviral control mechanisms that are distinguished by genetic polymorphism. The long-term objective of this research proposal therefore is to understand how genetic variation in host genes can contribute differently in innate immunity, its capacity to rapidly recognize and destroy viral pathogens at early times after infection and the molecular and cellular mechanisms controlling such host defenses. The Specific Aims herein will focus initially on the identification and characterization of host genes that contribute substantially to innate anti-MCMV immunity through classical Mendelian genetics studies. The approach is based on rapid phenotypic characterization of hybrid offspring after experimental MCMV infection and subsequent genome-wide genotypic identification of each individual. Using this high-throughput genetics strategy, chromosome locations will be identified in quantitative genetics strategies, confirmed in interval-specific congenic strains, and subsequently candidate genes will be assessed in prospective molecular and biochemical analyses. To facilitate identification of host virus resistance genes, we will also investigate NK cell recognition of virus infection in cellular cytotoxicity assays and virus strain variant selection will also be used to understand innate host defenses mechanistically. While NK cells employ multiple defense mechanisms to control viral pathogens immediately after infection and before adaptive immunity is competent, our studies will no doubt have important implications for human innate defenses in CMV and potentially other virus infections.

描述(申请人提供)：NK细胞是众所周知的识别和裂解病毒感染细胞的能力。事实上，缺乏NK细胞免疫的人类和小鼠的宿主防御系统非常容易受到铺天盖地和反复出现的疱疹病毒感染。在C57BL/6小鼠中，宿主抗小鼠巨细胞病毒(MCMV)免疫需要表达Ly49H激活受体的NK细胞识别其病毒编码的m157配体。然而，我们最近在NZW小鼠中发现，NK细胞对实验性MCMV感染没有控制作用，而对Ly49H+NK细胞有作用。在此，我们在MA/My小鼠中扩展了我们的发现。MA/MY株是值得注意的，因为它也表现出非常有效的NK细胞介导的MCMV感染控制，但该株的NK细胞不表达Ly49H受体。有趣的是，MA/MY对MCMV的抗性与MHC基因和非MHC基因密切相关。因此，我们发现NK细胞利用多种抗病毒控制机制，这些机制以遗传多态为特征。因此，这项研究的长期目标是了解宿主基因的遗传变异如何在先天性免疫中做出不同的贡献，其在感染后早期快速识别和摧毁病毒病原体的能力，以及控制这种宿主防御的分子和细胞机制。这里的具体目标首先将集中在通过经典孟德尔遗传学研究鉴定和表征对天然抗MCMV免疫有实质性贡献的宿主基因。该方法基于实验感染MCMV后杂交后代的快速表型特征以及随后对每个个体的全基因组基因型别鉴定。使用这种高通量遗传学策略，染色体位置将在定量遗传学策略中确定，并在区间特定的同源基因株中得到确认，随后候选基因将在未来的分子和生化分析中进行评估。为了便于识别宿主病毒耐药基因，我们还将在细胞毒性试验中研究NK细胞对病毒感染的识别，并将利用病毒株变异选择从机制上了解宿主的天然防御。虽然NK细胞使用多种防御机制在感染后立即控制病毒病原体，但在适应性免疫有效之前，我们的研究无疑将对人类对CMV和潜在的其他病毒感染的先天防御具有重要意义。