Human natural killer cell recognition of cytomegalovirus

项目总结/摘要 巨细胞病毒（CMV）感染了一半的美国人口， 对实体器官和造血干细胞移植患者具有特别风险， 免疫系统受损的个体。自然杀伤（NK）细胞，连同T细胞，需要 在个体的一生中控制这种持续性感染。我们最近意外地发现 携带独特的不变激活CD 94-NKG 2C受体的人NK细胞可以优先和 在远交人群中特异性应答CMV感染。我们之前已经证明， CD 94-NKG 2C受体识别HLA-E，一种基本上非多态性的主要组织相容性抗原， 在体内所有细胞和组织上表达的复杂蛋白质。CD 94-NKG 2C + NK的扩增 CMV感染后的细胞可能反映了对来自CMV或感染的宿主细胞的肽的识别 在HLA-E的背景下表达。在这个项目中，我们建议使用一种新颖而优雅的技术， 确定CMV感染细胞中HLA-E肽库的变化， HLA-E分子可以容易地纯化，用于洗脱结合的肽，然后进行比较质量分析， 光谱法本研究的目的是：1）确定HLA-E结合肽的性质， 未感染的细胞与CMV感染的细胞。我们将检验CMV感染的细胞将表现出 改变的HLA-E肽库，包括产生展示CMV编码的HLA-E蛋白， 肽，以及CMV诱导的宿主编码的肽。2)测定CMV诱导的HLA-E结合 - 活化性CD 94-NKG 2C与抑制性CD 94-NKG 2A受体的肽复合物，并测试 这些HLA-E-CMV诱导的肽复合物刺激表达HLA-E-CMV的原代人NK细胞的能力 CD 94-NKG 2C受体。鉴定CD 94-NKG 2C受体的高亲和力或优先HLA-E配体 将为未来的研究提供基础，以表征识别这些生物学后果。 新型配体。CMV疫苗是一个未满足的医疗需求，这些新的CMV诱导的疫苗的鉴定是一个重要的问题。 HLA-E-肽抗原可能为CMV的治疗或预防提供新的治疗策略 感染

Project Summary/Abstract Cytomegalovirus (CMV), which infects half of the US population, establishes a persistent infection for the life of the person and is of particular risk to solid organ and hematopoietic stem cell transplant patients and individuals with a compromised immune system. Natural killer (NK) cells, together with T cells, are required to control this persistent infection for the lifetime of the individual. We recently made the unexpected observation that human NK cells bearing a unique invariant activating CD94-NKG2C receptor can preferentially and specifically respond to CMV infection in the outbred human population. We had previously demonstrated that the CD94-NKG2C receptor recognizes HLA-E, an essentially non-polymorphic major histocompatibility complex protein that is expressed on all cells and tissues in the body. The expansion of CD94-NKG2C+ NK cells following CMV infection likely reflects the recognition of a peptide from CMV or the infected host cell expressed in the context of HLA-E. In this project, we propose to use a novel and elegant technique to determine the changes in the peptide repertoire of HLA-E in CMV-infected cells by creating soluble, secreted HLA-E molecules that can be easily purified for elution of bound peptides followed by comparative mass spectrometry. Aims of this project are: 1) To determine the nature of the peptides bound to HLA-E in uninfected versus CMV-infected cells. We will test the hypothesis that CMV-infected cells will demonstrate an altered HLA-E peptide repertoire, including the generation of HLA-E proteins displaying CMV-encoded peptides, as well as CMV-induced host-encoded peptides. 2) To measure the binding of CMV-induced HLA-E -peptide complexes for the activating CD94-NKG2C versus inhibitory CD94-NKG2A receptors and test the ability of these HLA-E-CMV-induced peptide complexes to stimulate primary human NK cells expressing the CD94-NKG2C receptor. Identifying high affinity or preferential HLA-E ligands for the CD94-NKG2C receptor will provide the foundation for future studies to characterize the biological consequences of recognition of these novel ligands. Vaccines for CMV are an unmet medical need and the identification of these novel CMV-induced HLA-E-peptide antigens may provide new therapeutic strategies for the treatment or prevention of CMV infection.