title: Interleukins and immunosuppressive factors: a regulatory system?
abstract: On exogenous stimulus immunocompetent leucocytes produce antigen-specific factors, which essentially determine the magnitude and duration of T-lymphocyte dependent immunoreactions. Interleukin 1 (IL-1, monokin) and interleukin 2 (IL-2, lymphokine) form a bimodal amplification system which may operate in vivo at the level of peripheral lymphoid organs, which interleukin 3 (IL 3, lymphokine) may function as a positive feed-back signal at the level of multipotential stem cells. The physiological IL-2 has wider importance, since the permanent expression of Il-2 gene due to the insertion of the viral promoter sequence (HTLV in human) led to uncontrolled proliferation of T-cells and to the development of lymphomas and leukemias of mature T-cell phenotype. On the afferent arc of immunoreactions endogenous factors mediate T-cell proliferation inhibitory effect probably via interaction with the interleukin system. Some practical aspects of these two antagonistic group of factors are presented and discussed.
mesh_terms: D000818:Animals; D002460:Cell Line; D003208:Concanavalin A / Q000494:pharmacology; D004274:DNA, Recombinant; D017977:Deltaretrovirus; D006801:Humans; D007108:Immune Tolerance; D007375:Interleukin-1 / Q000276:immunology*; D007376:Interleukin-2 / Q000235:genetics / Q000276:immunology*; D007377:Interleukin-3; D007938:Leukemia / Q000276:immunology; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000276:immunology*; D008223:Lymphoma / Q000276:immunology; D008264:Macrophages / Q000276:immunology; D051379:Mice; D009369:Neoplasms / Q000276:immunology; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D004274:DNA, Recombinant; D007375:Interleukin-1; D007376:Interleukin-2; D007377:Interleukin-3; D008222:Lymphokines; D010835:Phytohemagglutinins; D003208:Concanavalin A