Direct evidence that a class II molecule and a simple globular protein generate multiple determinants.
We have examined the individual contributions of the I-A kappa alpha chain, the I-A kappa beta chain, and the foreign antigen hen egg-white lysozyme (HEL) in the formation of the determinant being recognized by the T cell receptor. As functional probes we have used (a) a panel of 10 HEL-specific T cell hybridomas, (b) a panel of antigen-presenting cells (APC) possessing mutations in either the I-A kappa alpha or I-A kappa beta chains, and (c) proteolytic fragment of HEL and related synthetic peptides. The ability of the I-A kappa beta and I-A kappa alpha mutant cell lines to present antigen to the 10 T cell hybridomas divided these T cells into six distinct groups. These HEL-specific T cells therefore appear to recognize several distinct domains on the I-A kappa molecule. The 10 T cell hybrids were then shown to recognize at least three distinct determinants on the HEL molecule, with 8 of the 10 hybrids recognizing one of two major determinants HEL(46-61) or HEL(34-45). Combining the response patterns to the panel of I-A kappa mutant APC lines with the antigen specificity revealed that the 10 T cell hybrids recognized at least eight unique determinants formed by the I-A kappa alpha chains, I-A kappa beta chains, and HEL peptides. This analysis provides direct evidence that a large number of different determinants or T cell receptor ligands can be generated from a single Ia molecule and a simple globular protein.
P M
PM
Allen
D J
DJ
McKean
B N
BN
Beck
J
J
Sheffield
L H
LH
Glimcher
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D002460:Cell Line; D002645:Chickens; D000939:Epitopes / Q000032:analysis*; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006822:Hybrid Cells; D006825:Hybridomas; D051379:Mice; D009113:Muramidase / Q000276:immunology; D009154:Mutation; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*
D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D011948:Receptors, Antigen, T-Cell; D009113:Muramidase