CD4+ class I-restricted T cells specific for HIV gp160 315-329.
Mature, circulating, alpha beta T cells express either CD4 or CD8. In the majority of cases, CD4+ T cells recognize Ag in association with class II MHC molecules, while CD8+ T cells recognize Ag in association with class I MHC molecules. In this report we describe CD4+ class I-restricted T cell hybridomas and normal clones specific for the peptide 315-329 of HIV gp160 strain IIIb in association with H-2Dd. Two models were formulated to explain how CD4+ class I-restricted T cells could arise. First, they could represent aberrant selection of CD4+ cells on class I MHC molecules in the thymus. Alternatively, they could have been selected normally on class II; in this case the cells would display cross-reactive recognition of 315-329 in association with H-2Dd and an unknown Ag in association with class II. To distinguish these models, a second specificity was determined for the T cell clones. The normal clones recognized the class I molecule H-2Kk as alloantigen and thus were presumably positively selected in the thymus on class I MHC. CD4 was shown to be functional in these cells in that anti-CD4 mAb inhibited their proliferation: however, both Ag- and Con A-induced responses were inhibited, suggesting that a negative signal was delivered by the anti-CD4 mAb.
Moore
R L
RL
Department of Microbiology and Immunology, University of Maryland at Baltimore 21201.
Fox
B S
BS
D000818:Animals; D015704:CD4 Antigens / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002999:Clone Cells / Q000276:immunology; D015686:Gene Products, env / Q000276:immunology*; D006183:H-2 Antigens; D019302:HIV Envelope Protein gp160; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D006825:Hybridomas / Q000276:immunology; D007519:Isoantigens; D008213:Lymphocyte Activation; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D010446:Peptide Fragments / Q000276:immunology*; D011498:Protein Precursors / Q000276:immunology*
D015704:CD4 Antigens; D015686:Gene Products, env; D006183:H-2 Antigens; D019302:HIV Envelope Protein gp160; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D007519:Isoantigens; D010446:Peptide Fragments; D011498:Protein Precursors