The pigeon cytochrome c-specific T cell response of low responder mice. I. Identification of antigenic determinants on fragment 1 to 65.
An examination of the proliferative response to pigeon cytochrome c fragments 1 to 65 and 1 to 80 by T cells from mice that are low responders to the native molecule revealed that some of the strains could respond to antigenic determinants on these fragments. T cell clones derived from B10.A(3R) and B10.A(4R) mice were used to characterize the antigenic determinants on fragment 1 to 65. All of the clones recognized syngeneic A beta:A alpha Ia molecules as their restriction element. Three B10.A(3R) clones and six B10.A(4R) clones recognized fragment 39 to 65. Another four B10.A(4R) clones responded to fragment 1 to 38. By stimulating with a series of cytochrome c fragments from different species, as well as a synthetic peptide, it was possible to localize the antigenic determinant(s) recognized by the B10.A(3R) clones to residues 45 to 58. Each clone showed a unique pattern of responsiveness to the various fragments, suggesting a diversity of T cell receptors specific for the same peptide. One B10.A(3R) clone could be stimulated by many of the 1 to 65 fragments in association with allogeneic B10.SM presenting cells and by tuna fragment 1 to 65 in association with B10.M presenting cells, although the rank order of potency for several of the fragments was different than that observed with syngeneic antigen-presenting cells. In addition, the clone was poorly reactive to a synthetic peptide containing a conservative substitution, serine for threonine, at position 49. The implications of these results for subsite dissection (agretope and epitope) of the antigenic determinant recognized by this clone are discussed.
G
G
Suzuki
R H
RH
Schwartz
D000595:Amino Acid Sequence; D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D002417:Cattle; D002460:Cell Line; D002999:Clone Cells / Q000276:immunology; D010856:Columbidae; D003429:Cross Reactions; D003574:Cytochrome c Group / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D000939:Epitopes / Q000032:analysis*; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D010446:Peptide Fragments / Q000276:immunology*; D011817:Rabbits; D013045:Species Specificity; D013601:T-Lymphocytes / Q000276:immunology*
D003574:Cytochrome c Group; D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D010446:Peptide Fragments