Regulation of lymphocyte tumor necrosis factor receptors by IL-2.
Activated lymphocytes are known to express TNF receptors. The precise stimuli involved in induction and regulation of these receptors have not been elucidated. Our findings demonstrate that IL-2, alone and in serum-free conditions, can trigger and regulate TNF receptor expression on normal lymphocytes. Flow cytometric analyses demonstrated that the receptor was rapidly induced on CD4, CD8, and CD16+ cells after IL-2 stimulation. Receptors increased with culture duration, became maximal between days 5 and 9, and were maintained for 18 to 20 days in the presence of IL-2. By using 125I-TNF and FITC-TNF binding, we present evidence that IL-2 concentration determines the magnitude of lymphoid TNF receptor expression--influencing both the percentage of TNF-positive cells within the population and the number of receptors/cell. Collectively, our results are persuasive for consideration of IL-2 as a central mediator in the regulation of lymphocyte TNF receptors.
Owen-Schaub
L B
LB
Department of Tumor Biology, University of Texas M.D. Anderson Cancer Center, Houston 77030.
Crump
W L
WL
Morin
G I
GI
Grimm
E A
EA
D003602:Cytotoxicity, Immunologic; D004306:Dose-Response Relationship, Immunologic; D005434:Flow Cytometry; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D007700:Kinetics; D008213:Lymphocyte Activation; D010641:Phenotype; D011956:Receptors, Cell Surface / Q000096:biosynthesis / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor; D013602:T-Lymphocytes, Cytotoxic / Q000145:classification / Q000276:immunology / Q000378:metabolism*; D013861:Thiocyanates; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
D005452:Fluoresceins; D007376:Interleukin-2; D011956:Receptors, Cell Surface; D018124:Receptors, Tumor Necrosis Factor; D013861:Thiocyanates; D014409:Tumor Necrosis Factor-alpha; D016650:Fluorescein-5-isothiocyanate