Piepenbrink Kurt H, Gloor Brian E, Armstrong Kathryn M, Baker Brian M
Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, USA.
Methods Enzymol. 2009;466:359-81. doi: 10.1016/S0076-6879(09)66015-8. Epub 2009 Nov 13.
αβ T cell receptors (TCRs) recognize peptide antigens bound and presented by class I or class II major histocompatibility complex (MHC) proteins. Recognition of a peptide/MHC complex is required for initiation and propagation of a cellular immune response, as well as the development and maintenance of the T cell repertoire. Here, we discuss methods to quantify the affinities and thermodynamics of interactions between soluble ectodomains of TCRs and their peptide/MHC ligands, focusing on titration calorimetry, surface plasmon resonance, and fluorescence anisotropy. As TCRs typically bind ligand with weak-to-moderate affinities, we focus the discussion on means to enhance the accuracy and precision of low-affinity measurements. In addition to further elucidating the biology of the T cell mediated immune response, more reliable low-affinity measurements will aid with more probing studies with mutants or altered peptides that can help illuminate the physical underpinnings of how TCRs achieve their remarkable recognition properties.
αβ T细胞受体（TCRs）识别由I类或II类主要组织相容性复合体（MHC）蛋白结合并呈递的肽抗原。识别肽/MHC复合物对于细胞免疫反应的启动和传播以及T细胞库的发育和维持是必需的。在这里，我们讨论定量TCRs可溶性胞外域与其肽/MHC配体之间相互作用的亲和力和热力学的方法，重点是滴定热分析法、表面等离子体共振和荧光各向异性。由于TCRs通常以弱至中等亲和力结合配体，我们将讨论重点放在提高低亲和力测量的准确性和精确性的方法上。除了进一步阐明T细胞介导的免疫反应的生物学机制外，更可靠的低亲和力测量将有助于对突变体或改变的肽进行更深入的研究，这有助于阐明TCRs如何实现其卓越识别特性的物理基础。
