由HLA-DQ8呈现的T细胞对本地和拼接自身抗原的交叉反应的结构基础
Mai T Tran1, Jia Jia Lim1, Tiing Jen Loh1
1Infection and Immunity Program & Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
The Journal of biological chemistry
|July 29, 2024
概括
1型糖尿病中的T细胞受体对混合胰岛素 (HIP) 和本源胰岛素表位物进行交叉反应. 结构和突变研究揭示了驱动这种交叉反应性的关键残留物,为自身免疫性疾病机制提供了洞察力.
科学领域:
- 免疫学 免疫学 免疫学
- 分子生物学分子生物学
- 内分泌学 在内分泌学.
背景情况:
- 1型糖尿病 (T1D) 是一种由T细胞介导的自身免疫性疾病,具有强烈的HLA关联.
- 由HLA-DQ8呈现的自我,就像亲胰岛素C (PI40-54),都与T1D的发病有关.
- 来自T1D患者的CD4+T细胞克隆与混合胰岛素 (HIP) 发生交叉反应.
研究的目的:
- 研究T细胞受体 (TCR) 的交叉反应性,从T1D患者到本源胰岛素表位和HIP.
- 阐明TCR识别和交叉反应的基础分子机制.
- 为了在表位内确定决定TCR特异性的关键残留物.
主要方法:
- 从T1D患者中分离和表征CD4+T细胞克隆.
- 使用TCR--HLA-DQ8复合物的X射线晶体学进行结构分析.
- 氨酸扫描突变发生,以确定 TCR 结合的表位素残留的重要性.
主要成果:
- 在7个T细胞系中,有5个对多个HIP反应,对PI40-54.4呈现交叉反应性.
- 晶体结构揭示了PI40-54和HIPs的独特TCR结合机制.
- 在表位体中的P2,P7和P8残留物被确定为TCR特异性的关键.
结论:
- 建立了TCR对本源胰岛素和由HLA-DQ8呈现的HIP表位体的交叉反应的分子基础.
- 了解这些相互作用为T1D病原体提供了洞察力.
- 针对特定的表位残留物可以为T1D提供治疗策略.
相关概念视频
Antigens Involved in Adaptive Immunity
479
An antigen is any substance the immune system identifies as foreign and potentially harmful to the body, prompting an immune response. Antigens have two functional properties: immunogenicity and reactivity. Immunogenicity is the ability of an antigen to stimulate a specific immune response. At the same time, reactivity describes the antigen's ability to react with the cells and antibodies produced in response to it.
Complete Antigens
Complete antigens possess both immunogenicity and...
Complete Antigens
Complete antigens possess both immunogenicity and...
479
T Cell Activation and Clonal Selection
693
T cells are integral to our adaptive immune system, recognizing and effectively responding to foreign antigens. T cell activation and clonal selection are pivotal in orchestrating this immune response. This article elucidates these mechanisms, detailing the roles of cluster of differentiation (CD) markers, major histocompatibility complex (MHC) molecules, costimulatory signals, and the process of clonal selection.
Naive T cells that have not yet encountered an antigen express two primary CD...
Naive T cells that have not yet encountered an antigen express two primary CD...
693
Cross-reactivity
31.0K
Overview
31.0K
Diversity of Antigen Receptors
554
Antigen receptors are essential components of the immune system crucial in defending the body against foreign invaders. These receptors are present on the surface of B and T cells, enabling them to recognize antigens and mount an appropriate immune response.
Before encountering any antigen, lymphocytes express these receptors. On B cells, the antigen receptor is a membrane-bound antibody molecule called BCR; on T cells, it is a T cell receptor or TCR. B and T cell receptors are composed of two...
Before encountering any antigen, lymphocytes express these receptors. On B cells, the antigen receptor is a membrane-bound antibody molecule called BCR; on T cells, it is a T cell receptor or TCR. B and T cell receptors are composed of two...
554
Antigen Processing Pathways
973
MHC molecules are key players in the immune response, enabling T cells to recognize and respond to specific antigens. They are present on the surface of all nucleated cells in the body and are instrumental in presenting antigens to T cells and activating them. T cells recognize the MHC-antigen complex and initiate an immune response. MHC class I and MHC class II are two main types of MHC molecules, each associated with a distinct antigen processing pathway.
MHC Class I: Presenting Endogenous...
MHC Class I: Presenting Endogenous...
973
Cell-mediated Immune Responses
68.0K
Overview
68.0K


