USE OF PURIFIED MHC CLASS-I (H-2K(B)) MOLECULE AND ITS SYNTHETIC PEPTIDES FOR INHIBITION OF K-B-SPECIFIC T-SUPPRESSORS, AND THEIR INDUCTIONIN-VIVO BY MHC PEPTIDES

Six synthetic peptides of the MHC class I molecule were selected that correspond to individual regions of H-2K(b) domains alpha(1) (peptides 1 and 2) and alpha(2) (peptides 3-6). The K-b-specific T suppressors (Ts) induced in vivo in mice were treated with the peptide set and ass ayed for suppressing proliferation in the triple mixed lymphocyte cult ure. The Ts effector function was abolished by the alpha(2) (but not a lpha(2)) peptide complex and attenuated by each of the alpha(2) peptid es 4-6. The marked enrichment in Ts upon adsorption-elution on macroph ages was decreased by high doses of alpha(1) and alpha(2) peptides as well as by purified K-b on syngeneic and allogeneic monolayers, respec tively. The interaction of Ts receptors with some peptides suggests ef ficient activation of Ts in vivo upon mice immunization with alpha(2) peptides 5+6. The interaction of receptors of each T-cell subclass wit h the epitopes of the MHC class I molecule is under study.