Treatment of resting T lymphocytes with interferon-alpha/beta augments their proliferative response to activation signals delivered through their surface Ly-6 antigen.
Although the exact significance of Ly-6 antigens is unknown, recent evidence suggests they may provide an important alternative pathway for murine T-cell activation. Thus, Shevach et al. (1986, Fed. Proc. 45, 1131) discovered that cross-linking of Ly-6 antigens on the cell surface acts in concert with phorbol myristate acetate to trigger mitogenesis in T cells. Previously, we reported that surface expression of Ly-6 antigens on T cells is markedly increased following exposure to interferon-alpha/beta (IFN-alpha/beta). The purpose of the present work was to determine the effect of IFN-induced Ly-6 enhancement on Ly-6-mediated T-cell stimulation. Purified T cells were incubated in vitro for 1-27 hr with various doses (10-10(4) units/ml) of IFN-alpha/beta. This was found to result in various degrees of augmentation of the proliferative responses of these T cells to stimulation through their Ly-6 antigen. Surprisingly, while maximal enhancement of Ly-6 expression occurred only after the longest pulses with the highest IFN concentrations, treatment with as little as 100 units IFN/ml for 12 hr was sufficient to induce a dramatic (25-fold) and nearly maximal enhancement of proliferation. This high sensitivity to IFN-alpha/beta of the Ly-6 pathway of T-cell activation led us to speculate that this pathway may play a role in the immunomodulatory activities of IFN-alpha/beta.
D000818:Animals; D000950:Antigens, Ly / Q000276:immunology*; D002455:Cell Division / Q000187:drug effects; D005260:Female; D007370:Interferon Type I / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D000950:Antigens, Ly; D007370:Interferon Type I; D013755:Tetradecanoylphorbol Acetate