Role of Ly-6 in lymphocyte activation. II. Induction of T cell activation by monoclonal anti-Ly-6 antibodies.
The Ly-6 locus controls the expression and/or encodes for alloantigenic specificities found primarily on subpopulations of murine T and B lymphocytes. We have recently identified and characterized a new rat mAb, D7, that recognizes a nonpolymorphic Ly-6 specificity. After crosslinking by anti-Ig reagents or by Fc receptor-bearing accessory cells, mAb D7 could induce IL-2 production from T cell hybridomas, and in the presence of PMA could trigger a vigorous proliferative response in resting peripheral T cells. The addition of mAb D7 to cultures of antigen- and alloantigen-, but not mitogen-stimulated T cells resulted in a marked augmentation of the proliferative response. A number of other well-characterized mAbs to Ly-6 locus products could also stimulate a T cell proliferative response after crosslinking by anti-Ig and in the presence of PMA. These results strongly suggest that Ly-6 molecules may play a critical role in the T cell activation cascade, either as receptors for an unidentified soluble or cell-associated ligand or as transducing molecules that modulate signals initiated by antigen stimulation of the T3-Ti complex.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000938:Antigen-Presenting Cells / Q000502:physiology; D000950:Antigens, Ly / Q000276:immunology*; D002118:Calcium / Q000378:metabolism; D006825:Hybridomas / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D008934:Mitogens / Q000494:pharmacology; D011961:Receptors, Fc / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D007376:Interleukin-2; D008934:Mitogens; D011961:Receptors, Fc; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium