Induction of T cell activation by monoclonal anti-Thy-1 antibodies.
We have analyzed the requirements for T cell activation by monoclonal anti-Thy-1 antibodies (MAb). A large panel of unselected anti-Thy-1 MAb was capable of inducing a strong proliferative response in resting peripheral T cells and a rise in cytoplasmic free calcium ([Ca2+]i) in both peripheral T cells and a T cell hybridoma. Both of these responses required the interaction of a MAb bound to Thy-1 with a second layer of anti-Ig antibody. Induction of T cell proliferation also required an additional signal, which could be provided by PMA. T cell activation in this system was specific for the Thy-1 molecule, independent of the epitope on Thy-1 recognized by a given MAb, with the anti-Ig reagent was also independent of the type of anti-Ig used, as both polyvalent rabbit anti-rat Ig sera and a mouse MAb to rat Ig functioned as effective cross-linkers. All signals provided by the interaction of anti-Thy-1 MAb with anti-Ig preparations could also be reproduced by the simultaneous binding of two MAb recognizing independent epitopes on Thy-1. Although the physiological role of Thy-1 remains unknown, the model system described here should prove to be very useful in further analysis of the steps involved in the polyclonal activation of murine T cells.
Kroczek
R A
RA
Gunter
K C
KC
Seligmann
B
B
Shevach
E M
EM
D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal / Q000502:physiology*; D000938:Antigen-Presenting Cells / Q000276:immunology; D001666:Binding Sites, Antibody; D002118:Calcium / Q000378:metabolism; D003432:Cross-Linking Reagents; D000939:Epitopes / Q000276:immunology; D006825:Hybridomas / Q000276:immunology / Q000378:metabolism; D007518:Isoantibodies / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D003432:Cross-Linking Reagents; D000939:Epitopes; D007518:Isoantibodies; C035678:anti-Thy antibody; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium