Involvement of soluble mediator(s) different from interleukin (IL) 1 in the antigen-induced IL 2 receptor expression and proliferation of L3T4+ (CD4+) T lymphocytes.
Proliferation of T lymphocytes (T cells) requires the interaction of interleukin 2 (IL 2) with the high affinity form of the IL 2 receptor (IL 2R). IL 2 production as well as IL 2R expression are generally induced simultaneously in T cells by the recognition of specific antigen displayed on the surface of syngeneic antigen-presenting cells. The experiments described herein show that the expression of IL 2R has different requirements than the production of IL 2 (and other lymphokines). Stimulation of antigen-specific L3T4+ T cell lines with antigen-pulsed spleen cells (SC) treated with ultraviolet (UV) light results in efficient IL 2 production but only minimal proliferation due to reduced IL 2R expression, as compared to T cells stimulated by antigen and SC without UV light treatment. The reduced IL 2R expression/proliferation correlates with the absence of a soluble mediator(s) termed T cell-stimulating factor (TSF) in the supernatants of T cells stimulated with antigen-pulsed, UV light-irradiated SC. Addition of TSF of these T cells could at least partially restore the proliferative response or enhance IL 2R expression. Because TSF is present in the supernatant of T cells triggered by antigen and SC but is absent when the latter are UV light treated, we suggest that TSF is a product of metabolically active splenic antigen-presenting cells. The macrophage products interleukin 1 alpha + beta as well as some other cytokines show no TSF activity.
D000818:Animals; D000938:Antigen-Presenting Cells / Q000528:radiation effects; D000941:Antigens / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D002455:Cell Division; D005786:Gene Expression Regulation; D007376:Interleukin-2 / Q000096:biosynthesis / Q000502:physiology*; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D011971:Receptors, Immunologic / Q000096:biosynthesis*; D015375:Receptors, Interleukin-2; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D014466:Ultraviolet Rays
D000941:Antigens; D000945:Antigens, Differentiation, T-Lymphocyte; D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2