Coordinate expression of src family protooncogenes in T cell activation and its modulation by cyclosporine

Activation of T lymphocytes induces transcription of several important genes which encode lymphokines and lymphokine receptors as well as "proliferation complementary" protooncogenes like c-myc or c-fos. Recently, the expression of lck gene, one of the src family gene, has also been shown to be modulated during T cell activation. We, therefore, assessed the question of whether other src family genes are expressed during the activation of T cells and of whether cyclosporine, a potent immunosuppressive drug, affects expression of these genes. We examined the expression of four different src family genes (lck, c-src, fyn, and c-fgr) in addition to the expression of IL-2, c-fos, c-myc, and actin genes in murine T cells which were activated with PMA plus ionomycin or PMA plus anti-CD3 mAb. We found that T cell activation was associated with the up-regulation of these src family genes and that the expression of these genes was specifically blocked in the presence of cyclosporine indicating that these activation-related genes were coordinately regulated.