title: CD8 controls T cell cross-reactivity.
abstract: Estimates of human αβ TCR diversity suggest that there are <10(8) different Ag receptors in the naive T cell pool, a number that is dwarfed by the potential number of different antigenic peptide-MHC (pMHC) molecules that could be encountered. Consequently, an extremely high degree of cross-reactivity is essential for effective T cell immunity. Ag recognition by T cells is unique in that it involves a coreceptor that binds at a site distinct from the TCR to facilitate productive engagement of the pMHC. In this study, we show that the CD8 coreceptor controls T cell cross-reactivity for pMHCI Ags, thereby ensuring that the peripheral T cell repertoire is optimally poised to negotiate the competing demands of responsiveness in the face of danger and quiescence in the presence of self.
authors.affiliation: Department of Infection, Immunity and Biochemistry, Cardiff University School of Medicine, Cardiff, UK. wooldridgel@cardiff.ac.uk
authors.forename: Linda
authors.initials: L
authors.lastname: Wooldridge
authors.forename: Bruno
authors.initials: B
authors.lastname: Laugel
authors.forename: Julia
authors.initials: J
authors.lastname: Ekeruche
authors.forename: Mathew
authors.initials: M
authors.lastname: Clement
authors.forename: Hugo A
authors.initials: HA
authors.lastname: van den Berg
authors.forename: David A
authors.initials: DA
authors.lastname: Price
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Sewell
mesh_terms: D017951:Antigen Presentation; D016827:CD8 Antigens / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D002469:Cell Separation; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D011948:Receptors, Antigen, T-Cell / Q000276:immunology
chemical_list: D016827:CD8 Antigens; D015395:Histocompatibility Antigens Class I; D011948:Receptors, Antigen, T-Cell