Mechanisms Regulating Human NK Cell Cytotoxicity

人类 NK 细胞细胞毒性的调节机制

基本信息

批准号：
9919370
负责人：
DANIEL D BILLADEAU
金额：
$ 39.75万
依托单位：
MAYO CLINIC ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-05-17 至 2022-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9919370
关键词：
Actins Adhesions Affect B-Lymphocytes Binding CDC42 gene Cell Adhesion Cell Polarity Cell membrane Cell physiology Cell-Cell Adhesion Cell-Mediated Cytolysis Cells Cellular Stress Complex Cutaneous Cytokinesis Cytolysis Cytoplasmic Granules Cytoskeleton DOCK1 protein Data Defect Detection Development Dynein ATPase Effector Cell Event Exocytosis F-Actin Family Family member Filament GTP Binding Generations Genes Guanine Nucleotide Exchange Factors Guanosine Triphosphate Hematopoietic Herpesviridae Human Human Cloning Immune Immune system Immunologic Deficiency Syndromes Impairment Incidence Integrins Job&apos s Syndrome Lead Lymphocyte Subset Lytic Mediating Membrane Microtubule-Organizing Center Microtubules Molecular Molecular Abnormality Motor Mus Natural Killer Cells Nonmuscle Myosin Type IIA Outcome Paper Papillomavirus Infections Pathway interactions Patients Process Proteins Proteomics Publishing Recurrence Regulation Role Signaling Molecule Suggestion Synapses Syndrome T-Lymphocyte Talin Testing Tubulin Virus Virus Diseases base cancer cell cell killing chemokine congenital immunodeficiency cytokine cytotoxic cytotoxicity depolymerization experimental study immunological synapse insight loss of function mutation member novel polarized cell receptor recruit recurrent infection

项目摘要

NK cells are a subpopulation of lymphocytes whose unique receptors facilitate the detection of infected, transformed, or `stressed' cells. This immune recognition subsequently leads to the development of NK cell- mediated cytotoxicity or the generation of cytokines and chemokines that activate other components of the immune system. Patients with hyper-IgE syndrome (HIES) have immune dysregulation and can be affected by recalcitrant cutaneous herpes virus and papillomavirus infections. A major genetic abnormality found in these patients is deletion or loss-of-function mutations in the gene encoding Dedicator of Cytokinesis 8 (DOCK8), a guanine nucleotide exchange factor (GEF) for Cdc42. The high incidence of recurrent cutaneous viral infections in DOCK8-deficient patients is suggestive of defects in natural killer (NK) cell function. In fact, others and we have recently shown that NK cells deficient in DOCK8 have reduced lytic function, decreased adhesion, F-actin accumulation at the cytotoxic synapse and an inability to polarize lytic granules toward the target cell. However, how DOCK8 can regulate so many critical steps in the development of NK cell killing is not known. It is our central hypothesis that the DOCK8-interactome coordinates the regulation of the actin and microtubule cytoskeletons to facilitate NK cell polarization and effect NK cellular cytotoxicity. Based on the preliminary data included in this proposal, we hypothesize that: (a) DOCK8 activation of CDC42 is critical to the development of NK cell killing; (b) DOCK8 interaction with WASP is critical for its localization and F-actin generation at the NKIS; (c) talin recruitment by DOCK8 mediates NK cell – target adhesion; (d) HkRP3, a hematopoietically expressed protein that interacts with DOCK8 is involved in MTOC polarization and lytic granule clustering and affects lytic granule clustering through its interactions with tubulin and the dynein motor complex; (e) septins are DOCK8 interacting proteins that regulate NK cell killing; (f) BORG stabilization of septin filaments is impaired by active Cdc42 in order to regulate NK cell killing. In order to test these hypotheses we will: (1) Determine the mechanism by which DOCK8 regulates F-actin dynamics and cell adhesion; (2) Define the mechanism by which HkRP3 regulates lytic granule convergence and MTOC polarization; (3) Determine the role of septins in the regulation of the NK cell cytotoxicity. The outcome of the proposed experiments will provide an experimental basis for understanding the molecular events that are involved in the regulation of NK cell effector functions, and will, in a broader context, advance our understanding of fundamental processes in cellular activation leading to F-actin regulation, MTOC polarization and granule exocytosis. Moreover, the information obtained through these studies will likely instruct how DOCK8 is functioning in other immune cells.

NK 细胞是淋巴细胞的一个亚群，其独特的受体有助于检测受感染的、这种免疫识别随后导致 NK 细胞的发育。介导的细胞毒性或激活细胞其他成分的细胞因子和趋化因子的产生高 IgE 综合征 (HIES) 患者存在免疫失调，并可能受到以下因素的影响。顽固性皮肤疱疹病毒和乳头瘤病毒感染是在这些疾病中发现的主要遗传异常。患者的细胞分裂奉献者 8 (DOCK8) 编码基因缺失或功能丧失突变， Cdc42 的鸟嘌呤核苷酸交换因子 (GEF) 复发性皮肤病毒的发生率很高。 DOCK8 缺陷患者的感染表明自然杀伤 (NK) 细胞功能存在缺陷。我们最近发现，缺乏 DOCK8 的 NK 细胞会降低溶解功能，降低粘附、F-肌动蛋白在细胞毒性突触处积聚以及无法将裂解颗粒极化至然而，DOCK8 如何调节 NK 细胞杀伤过程中的许多关键步骤？我们的中心假设是 DOCK8 相互作用组协调肌动蛋白的调节。和微管细胞骨架，促进 NK 细胞极化并影响 NK 细胞的细胞毒性。根据该提案中包含的初步数据，我们追求：（a）CDC42 的 DOCK8 激活 (b) DOCK8 与 WASP 的交互对其本地化至关重要 NKIS 中的 F-肌动蛋白生成；(c) DOCK8 的 talin 募集介导 NK 细胞 - 靶标粘附； HkRP3 是一种造血表达蛋白，与 DOCK8 相互作用，参与 MTOC 极化和裂解颗粒聚集并通过其与微管蛋白和动力蛋白的相互作用影响裂解颗粒聚集运动相互作用复合物；(e) septin 是调节 NK 细胞杀伤的 DOCK8 蛋白；(f) BORG 稳定化；活性 Cdc42 会损害 septin 丝，以调节 NK 细胞杀伤。假设我们将：（1）确定 DOCK8 调节 F-肌动蛋白动力学和细胞的机制 (2)明确HkRP3调节溶解颗粒聚集和MTOC的机制极化；(3)确定septins在调节NK细胞细胞毒性中的作用。所提出的实验将为理解分子事件提供实验基础参与 NK 细胞效应功能的调节，并将在更广泛的背景下推进我们的研究了解导致 F-肌动蛋白调节、MTOC 极化的细胞激活的基本过程此外，通过这些研究获得的信息可能会指导如何进行。 DOCK8 在其他免疫细胞中发挥作用。