title: The molecular basis of alloreactivity in antigen-specific, major histocompatibility complex-restricted T cell clones.
abstract: We have studied the relationship between major histocompatibility complex (MHC)-restricted antigen recognition and alloreactivity by examining T cell receptor (TCR) alpha and beta gene expression in cytochrome c-specific, Ek alpha:Ek beta (Ek)-restricted helper T cell clones derived from B10.A mice. The clones could be segregated on the basis of four distinct alloreactivity patterns. Clones cross-reactive for three different allogeneic la molecules (As alpha:As beta [As], Ab alpha:Ab beta [Ab], Ek alpha: Eb beta [Eb]) expressed the same V alpha and V beta gene segments, generating the distinct alloreactive specificities via unique V alpha-J alpha and V beta-D beta-J beta joining events. Ek alpha:Es beta (Es)-alloreactive B10.A clones expressed the same V alpha, J alpha, and V beta segments as an Es-restricted, Ek-alloreactive, cytochrome c-specific, H-2-congenic B10.S(9R) clone. This homology between TCRs mediating allorecognition of la molecules and recognition of the same la molecules as restriction elements associated with nominal antigen suggests that MHC-restricted recognition and allorecognition represent differences in the affinity of the TCR-MHC molecule interaction.
mesh_terms: D000818:Animals; D002999:Clone Cells / Q000276:immunology; D010856:Columbidae / Q000276:immunology; D003574:Cytochrome c Group / Q000276:immunology; D004247:DNA / Q000235:genetics; D004274:DNA, Recombinant; D000939:Epitopes / Q000276:immunology*; D005260:Female; D005803:Genes, Immunoglobulin; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007519:Isoantigens / Q000276:immunology*; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex; D008297:Male; D051379:Mice; D009036:Moths / Q000276:immunology; D009693:Nucleic Acid Hybridization; D011948:Receptors, Antigen, T-Cell / Q000235:genetics* / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D003574:Cytochrome c Group; D004274:DNA, Recombinant; D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D007519:Isoantigens; D011948:Receptors, Antigen, T-Cell; D004247:DNA