| Abstract: | When murine T lymphocyte clones were cultured with purified recombinant IL 2, a dose-dependent increase in the production of granulocyte-macrophage colony-stimulating factor (GM-CSF) was observed. Whereas these clones produced both GM-CSF and multi-lineage CSF (multi-CSF) when cultured with concanavalin A, IL 2 induced the production of GM-CSF in the virtual absence of detectable multi-CSF. In addition, IL 2 synergistically enhanced the production of both GM-CSF and multi-CSF by some antigen- or Con-A-stimulated clones. Like Con-A-induced CSF production, GM-CSF production in the presence of IL 2 required protein synthesis but could occur in the absence of proliferation by the clone. Analysis of dose-response curves for stimulation of CSF production by Con A in the presence and absence of IL 2 suggested that Con A and IL 2 activated GM-CSF synthesis by different mechanisms. These results indicate that the coordinate production of two factors by a single T cell clone stimulated with Con A can be dissociated when the clone is stimulated with IL 2. |
