Structure, Function and Mechanistic Analysis of LAG3

LAG3的结构、功能及机理分析

基本信息

批准号：
10317043
负责人：
Roy A Mariuzza
金额：
$ 71.2万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-08 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10317043
关键词：
Address Affinity Agonist Amino Acids Autoimmune Autoimmunity Binding Biological Process Biophysics Blocking Antibodies CD3 Antigens CD4 Positive T Lymphocytes CD8-Positive T-Lymphocytes CTLA4 gene Cell physiology Cells Chronic Clinic Clinical Trials Clustered Regularly Interspaced Short Palindromic Repeats Complex Crystallization Data Development Disease Dissection Epitopes Generations Goals Human Immune Immunity Immunotherapeutic agent Immunotherapy Inflammatory Lead Ligands MHC Class II Genes Mediating Modeling Monoclonal Antibodies Mus Mutagenesis Mutant Strains Mice Play Positioning Attribute Reagent Receptor-CD3 Complex, Antigen, T-Cell Research Role Site Structure T-Lymphocyte Testing Therapeutic Therapeutic Monoclonal Antibodies Tissues Treatment Efficacy Viral Cancer Virus Diseases Work antagonist anti-PD-1 cancer therapy comparative effector T cell exhaust in vitro Assay insight mutant novel overexpression prevent programmed cell death protein 1 receptor reconstitution response screening panel targeted treatment tool tumor

项目摘要

LAG3 (CD233) is an inhibitory receptor that plays a critical role in controlling T cell tolerance, preventing autoimmunity and limiting immune-mediated tissue damage. It is highly upregulated on exhausted T cells in tumors and in chronic viral infections, limiting the development of sterilizing immunity. Consequently, LAG3 is now a major immunotherapeutic target for the treatment of cancer and other diseases, with multiple clinical trials ongoing. Despite extensive analysis of LAG3 for over 30 years and multiple LAG3 targeting therapeutics in the clinic, very little is known about the mechanism of action of LAG3 and thus how to develop optimal LAG3- targeting therapeutics, especially agonists. While it is assumed that the primary and perhaps only functionally relevant ligand for LAG3 is MHC class II, there are several observations including our recent preliminary studies that suggest that there are additional biophysical requirements for LAG3 to function. AIM 1: Define and compare LAG3 interaction with its ligands. We will address 3 questions: (A) Which domains and residues mediate LAG3 interaction with its ligands? (B) Can the association of LAG3 with its ligands be disrupted by different anti-LAG3 Abs? (C) What LAG3 residues mediate ligand interaction? AIM 2: Determine crystal structures of LAG3 and of LAG3:Ab and LAG3:MHC class II complexes. We will address the structural basis for the biological function of LAG3 by asking 3 questions: (A) What unique structural features of LAG3 distinguish it from CD4? (B) What is the structure of LAG3:Ab complexes? (C) What is the structure of LAG3:MHC class II complexes? AIM 3: Determine the functional impact of LAG3 interaction with its ligands. We will address 3 questions: (A) Is LAG3 association with its various ligands required for its function? (B) Does LAG3 interaction with its various ligands have a differential impact on its function in tumor models? (C) Is blocking the association of LAG3 with its different ligands have differential therapeutic benefit? This project will have a significant impact on our understanding of the mechanism of action of LAG3, as well as provide further insight into the generation of enhanced therapeutic reagents that block or enhance LAG3 function. Given that we have determined the function of LAG3 on regulatory and effector T cell function, have been studying LAG3 function of ~19 years, have available to us a variety of unique tools to probe its function and have assembled a strong and technically diverse collaborative team, we are in the best position to conduct this research.

LAG3 (CD233) 是一种抑制性受体，在控制 T 细胞耐受性、预防自身免疫和限制免疫介导的组织损伤。它在耗尽的 T 细胞上高度上调肿瘤和慢性病毒感染，限制了杀菌免疫力的发展。因此，LAG3 是现在是治疗癌症和其他疾病的主要免疫治疗靶点，已进行多项临床试验正在进行中。尽管对 LAG3 进行了超过 30 年的广泛分析，并且在多个 LAG3 靶向治疗中临床上，人们对 LAG3 的作用机制以及如何开发最佳的 LAG3 知之甚少。靶向治疗，尤其是激动剂。虽然假设主要的并且可能只是功能性的 LAG3 的相关配体是 MHC II 类，有一些观察结果，包括我们最近的初步研究这表明 LAG3 的功能需要额外的生物物理要求。目标 1：定义并比较 LAG3 与其配体的相互作用。我们将解决 3 个问题：(A) 哪一个结构域和残基介导 LAG3 与其配体的相互作用？ (B) LAG3 能否与其配体结合会被不同的抗 LAG3 抗体破坏吗？ (C) 哪些 LAG3 残基介导配体相互作用？目标 2：确定 LAG3 以及 LAG3:Ab 和 LAG3:MHC II 类复合物的晶体结构。我们将通过提出 3 个问题来解决 LAG3 生物学功能的结构基础：(A) 有什么独特的结构 LAG3的特点与CD4有何区别？ (B) LAG3:Ab 复合物的结构是什么？（三）什么是 LAG3：MHC II 类复合物的结构？目标 3：确定 LAG3 与其配体相互作用的功能影响。我们将解决3个问题： (A) LAG3 与其各种配体的结合是其功能所必需的吗？ (B) LAG3 与其相互作用吗？不同的配体对其在肿瘤模型中的功能有不同的影响吗？ (C) 正在阻止 LAG3 的关联其不同的配体有不同的治疗益处吗？该项目将对我们对 LAG3 作用机制的理解产生重大影响，因为并提供对增强治疗试剂的生成的进一步见解，这些试剂可以阻断或增强LAG3功能。鉴于我们已经确定了 LAG3 对调节和效应器的功能 T细胞功能，已经研究LAG3功能~19年，已经提供给我们多种独特的工具来探索其功能，并组建了一支强大且技术多样化的协作团队，我们最适合开展这项研究。