title: Activation of murine T cells by streptococcal pyrogenic exotoxin type A. Requirement for MHC class II molecules on accessory cells and identification of V beta elements in T cell receptor of toxin-reactive T cells.
abstract: We investigated the mechanisms of murine T cell activation by streptococcal pyrogenic exotoxin type A (SPE A), focusing on the role of MHC class II molecules on accessory cells (AC) and V beta usage in alpha beta TCR of SPE A-reactive T cells in comparison with staphylococcal enterotoxin B-reactive T cells. L cells transfected with I-Ab genes functioned as effective AC for SPE A-induced responses by C57BL/6 T cells, proliferation, and IL-2 production, but control L cells were not effective AC. Anti-I-Ab mAb inhibited the SPE A-induced responses. Staphylococcal enterotoxin B-induced C57BL/6 T cell blasts were composed of cells bearing V beta 3, members of the V beta 8 family, and V beta 11. Most of the SPE A-induced T cell blasts (about 80%) bore V beta 8.2. mAb reactive to V beta 8.2 markedly inhibited SPE A-induced T cell responses. Apparently, SPE A activates mainly T cells bearing V beta 8.2 in physical association with MHC class II molecules expressed on AC. We also discuss the pathogenic activities of SPE A in relation to toxic shock syndrome.
authors.affiliation: Department of Microbiology, Tokyo Women's Medical College, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Imanishi
authors.forename: H
authors.initials: H
authors.lastname: Igarashi
authors.forename: T
authors.initials: T
authors.lastname: Uchiyama
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology*; D001426:Bacterial Proteins; D001427:Bacterial Toxins / Q000494:pharmacology*; D004768:Enterotoxins / Q000494:pharmacology; D005098:Exotoxins / Q000494:pharmacology*; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000502:physiology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D008297:Male; D008565:Membrane Proteins; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D011948:Receptors, Antigen, T-Cell / Q000032:analysis*; D013297:Streptococcus pyogenes / Q000378:metabolism*; D018089:Superantigens; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004768:Enterotoxins; D005098:Exotoxins; D000949:Histocompatibility Antigens Class II; D008565:Membrane Proteins; D011948:Receptors, Antigen, T-Cell; C117980:SpeA protein, Streptococcus pyogenes; D018089:Superantigens; C030107:enterotoxin F, Staphylococcal; C027951:erythrogenic toxin