The TcR-CD3 complex is required for activation of human lymphocytes with staphylococcal enterotoxin A.
The involvement of the T-cell receptor (TcR)-CD3 complex in activation of human mononuclear cells by staphylococcal enterotoxin A (SEA) was investigated. TcR-CD3 molecular complex expression was modulated with monoclonal anti-CD3 antibodies. The proliferative response of such modulated cells to optimal doses of phytohaemagglutinin and monoclonal anti-CD3 antibodies and to suboptimal doses of SEA was greatly impaired. In concentrations above 1 ng/ml, SEA could also activate the modulated cells to a certain extent, apparently due to reexpression of low levels of the TcR-CD3 molecular complex during incubation. TcR-CD3 modulation decreased the ability of SEA-activated cells to produce interleukin 2 and gamma interferon. Analysis of cloned cells revealed that SEA could only activate CD3+ but not CD3- clones. Both CD4+ and CD8+ clones were activated. The results show that SEA activates human T cells by a mechanism involving the TcR-CD3 molecular complex.
Lando
P A
PA
Pharmacia LEO Therapeutics AB, IDEON-Malmo, Sweden.
Dohlsten
M
M
Kalland
T
T
Sjögren
H O
HO
Carlsson
R
R
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D017252:CD3 Complex; D002455:Cell Division; D002469:Cell Separation; D002999:Clone Cells; D004768:Enterotoxins / Q000494:pharmacology*; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D004768:Enterotoxins; D007376:Interleukin-2; D010835:Phytohemagglutinins; D011948:Receptors, Antigen, T-Cell; C026066:enterotoxin A, Staphylococcal; D007371:Interferon-gamma