Concanavalin A-induced interferon gamma production by murine spleen cells and T cell lines. Lack of correlation with Lyt 1,2 phenotype

Concanavalin A(Con A)-induced interferon-gamma (IFN gamma) production by resting or preactivated murine spleen cells negatively selected with monoclonal antibodies specific for Lyt 1,2 antigens plus complement (C) and by interleukin 2(IL-2)-dependent T cell lines of different Lyt phenotype was studied. The data show that most of the IFN-gamma produced upon stimulation of resting spleen cells was a product of Lyt 1+2+ cells. Lyt 1-2+ cells were negative for IFN gamma production. When spleen cells that had been preactivated for 3 days with Con A were restimulated with Con A, Lyt 1+2+, Lyt 1+2- as well as Lyt 1-2+ cells produced IFN gamma in a relationship of approximately 5:3:1. In both cases the picture remained unaltered independently when the supernatants were harvested after 1, 3 or 5 days. Furthermore, two IL-2 dependent T cell lines were studied in regard to Con A-induced IFN gamma production. Line 1.3 was Thy 1+, Lyt 1-2+, whereas line 20.9. was Thy 1+, Lyt 1+2-. Both lines produced initially high titers of IFN gamma upon stimulation with Con A. After prolonged passage in vitro, however, they progressively lost the capacity to produce IFN gamma.