What does the T-cell receptor recognize when it docks on an MHC-encoded restricting element?
The postulate is analyzed that single V-gene segments encode recognition of the allele-specific determinants (a) required for the restrictive response of the alphabeta TCR to peptide. The consequence of this is that the positively selected V-domain, Valpha or Vbeta, engages an allele-specific determinant (a) on one subunit or domain of the MHC-encoded restricting element. The entrained V-domain docks on an invariant determinant (i) on the complementing subunit or domain. Consequently, each functional V-domain expresses an anti-a site and an anti-i site, and all subunits or domains of MHC-encoded restricting elements express an a- and i-determinant. The evidence, both biological and structural, discussed here strongly supports this postulate which has far reaching consequences.
Cohn
Melvin
M
Conceptual Immunology Group, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, United States. cohn@salk.edu
D000483:Alleles; D003062:Codon; D006649:Histocompatibility Antigens / Q000235:genetics / Q000276:immunology*; D018448:Models, Immunological; D021122:Protein Subunits / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D017452:Receptors, IgG / Q000276:immunology
D003062:Codon; C080568:Fc gamma receptor IIA; D006649:Histocompatibility Antigens; D021122:Protein Subunits; D011948:Receptors, Antigen, T-Cell; D017452:Receptors, IgG