Natural killer cell and T-cell crosstalk in CMV infection

CMV 感染中的自然杀伤细胞和 T 细胞串扰

• 批准号: 9398188
• 负责人: KATHARINE C HSU
• 金额: $ 30.63万
• 依托单位: SLOAN-KETTERING INST CAN RESEARCH
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-15 至 2019-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9398188
• 关键词: Activated Natural Killer Cell; Adoptive Transfer; Affect; Alpha Cell; Antigen-Presenting Cells; Antigens; Autologous; Binding; Biological Assay; Blood specimen; C57BL/6 Mouse; CD8-Positive T-Lymphocytes; Cell Communication; Cell Transplants; Cell physiology; Cell surface; Cells; Chronic; Cytomegalovirus; Cytomegalovirus Infections; Cytotoxic T-Lymphocytes; Data; Dendritic Cells; Development; Equilibrium; Goals; Hematopoietic; Human; Immune; Immune response; Immune system; Immunocompromised Host; In Vitro; Incubated; Individual; Infection; Innate Immune System; Kinetics; Knowledge; Lymphocyte; Maintenance; Mediating; Memory; Modeling; Morbidity - disease rate; Mus; Natural Immunity; Natural Killer Cells; Newborn Infant; Organ; PDCD1LG1 gene; Patients; Peptides; Phenotype; Physiologic pulse; Population; Recovery; Shapes; Solid; Stem cell transplant; Surface; System; T cell response; T-Cell Proliferation; T-Lymphocyte; Transplant Recipients; Transplantation; Up-Regulation; Viral; Virus; Virus Diseases; cohort; comparative; hematopoietic cell transplantation; in vivo; inhibiting antibody; insight; mortality; mouse model; novel; pathogen; peripheral blood; prevent; reconstitution; response; seropositive

ABSTRACT Human cytomegalovirus (HCMV) is the most common cause of congenital viral infection and an important cause of morbidity and mortality following solid organ and hematopoietic cell transplantation. Understanding how the immune system responds to HCMV is vital to the efforts to achieve efficient eradication of infection. This proposal aims to identify novel relationships between NK cells and T cells during HCMV infection, with the central hypothesis that a strong T cell response to HCMV infection can abrogate the emergence of an NK memory phenotype; reciprocally, a HCMV-activated NK cell can regulate the magnitude of the T-cell response. Using a unique fully autologous in vitro HCMV infection system, regulatory relationships between NK cells and T cells can be investigated and identified. Preliminary studies have generated the novel finding that direct interaction of NK cells with HCMV-infected dendritic cells induces PD-L1 surface expression on NK cells, which directly inhibits antibody-mediated T cell proliferation. To determine the impact of PDL1+ NK cell on HCMV antigen specific T cells, T cell responses to HCMV infection will be stimulated by the use of an artificial antigen-presenting cell pulsed with CMVpp65 peptides. Co-incubation of CMV-activated PDL1+ NK cells and CMV- sensitized T cells will permit elucidation of regulatory effects of one lymphocyte on the other. Additionally, preliminary data from an in vivo murine model has recapitulated findings in the human studies, showing a significant increase in the number of PDL1+ NK cells following MCMV infection of C57BL/6 mice. Using genetically novel murine systems, the in vivo impact of PDL1+ NK cells on MCMV-specific T cell responses and the efficiency of viral clearance will be determined. These murine models will allow for correlation of strength of the NK cell response with CMV-specific T cell responses and will also provide insight to how this relationship is controlled. The understanding of NK and T cell relationships developed in the in vitro and in vivo studies will be applied to the study of expansion and maintenance of adaptive NKG2C+ NK cells in healthy human donors as well as in patients with CMV reactivation following stem cell transplantation. The availability of blood samples from a cohort of hematopoietic cell transplant patients with CMV reactivation provides the unique opportunity to examine the NK and T cell repertoire in the setting of CMV infection. These studies will describe novel mechanisms that will expand existing knowledge on the balance of the adaptive and innate immune systems during viral infection and will provide further insight to mechanisms that can be targeted to prevent reactivation and chronic viral infection.

摘要 人巨细胞病毒（HCMV）是先天性病毒感染的最常见原因， 实体器官和造血细胞移植后发病和死亡重要原因 移植了解免疫系统如何对HCMV作出反应对于这些努力至关重要 以实现有效根除感染。该提案旨在确定新的关系 在HCMV感染过程中NK细胞和T细胞之间的相互作用，中心假设是一个强的T细胞 细胞对HCMV感染的应答可以消除NK记忆表型的出现; 因此，HCMV激活的NK细胞可以调节T细胞应答的幅度。 使用独特的完全自体体外HCMV感染系统，调节关系 NK细胞和T细胞之间的关系可以研究和鉴定。初步研究已经 产生了新的发现，NK细胞与HCMV感染的树突状细胞的直接相互作用， 诱导NK细胞上的PD-L1表面表达，其直接抑制抗体介导的T细胞 增殖为了确定PDL 1 + NK细胞对HCMV抗原特异性T细胞的影响， 对HCMV感染的反应将通过使用人工抗原呈递细胞来刺激 用CMVpp 65肽脉冲。CMV活化的PDL 1 + NK细胞和CMV-1的共孵育 致敏的T细胞将允许阐明一个淋巴细胞对另一个淋巴细胞的调节作用。 此外，来自体内鼠模型的初步数据概括了在实验中的发现。 人类研究，显示在以下情况下，PDL 1 + NK细胞的数量显著增加 C57 BL/6小鼠的MCMV感染。使用基因新颖的鼠系统， PDL 1 + NK细胞对MCMV特异性T细胞应答和病毒清除效率的影响将被评估。 测定这些鼠模型将允许NK细胞应答强度的相关性 与CMV特异性T细胞反应，也将提供洞察这种关系是如何 控制。对NK细胞和T细胞关系的理解是在体外和体内发展起来的。 体内研究将用于研究适应性NKG 2C + NK的扩增和维持， 健康人供体以及干细胞移植后CMV再活化患者中的细胞 移植造血细胞移植队列血液样本的可用性 CMV再激活患者提供了检查NK和T细胞的独特机会， 在CMV感染的情况下，这些研究将描述新的机制， 扩大现有的知识，适应性和先天免疫系统的平衡， 病毒感染，并将提供进一步的洞察机制，可以有针对性地预防 再活化和慢性病毒感染。