Affinity threshold for thymic selection through a T-cell receptor-co-receptor zipper.
The affinity of the T-cell receptor (TCR) for self antigen is the basis for the selection of a useful (MHC-restricted) and safe (self-tolerant) T-cell repertoire. However, it has been difficult to understand how thymocytes measure ligand affinity and translate this signal into a cellular response. In this Opinion article, we propose a new model that describes how the TCR discriminates between low- and high-affinity ligands, which is based on the duration of TCR-ligand interactions and a 'zipper' mechanism that mediates the interaction of the TCR and co-receptor molecules to initiate negative-selection signalling.
Palmer
Ed
E
Department of Nephrology and Biomedicine, Laboratory of Transplantation Immunology, University Hospital Basel, Basel, Switzerland. ed.palmer@unibas.ch
Naeher
Dieter
D
D000818:Animals; D001324:Autoantigens / Q000276:immunology / Q000378:metabolism; D006801:Humans; D038041:Lymphopoiesis; D008285:Major Histocompatibility Complex / Q000502:physiology; D051379:Mice; D011948:Receptors, Antigen, T-Cell / Q000276:immunology* / Q000378:metabolism; D037182:T-Cell Antigen Receptor Specificity; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D013950:Thymus Gland / Q000276:immunology*
D001324:Autoantigens; D011948:Receptors, Antigen, T-Cell