Effects of eleven cytokines and of IL-1 and tumor necrosis factor inhibitors in a human B cell assay.
The effects of different recombinant human cytokines and cytokine inhibitors were compared in a culture system in which cell contact with mutant EL-4 thymoma cells of murine origin efficiently stimulates human B cell proliferation and Ig secretion in conjunction with human T cell supernatant. IL-1 alpha, IL-1 beta, TNF-alpha, and IL-2 co-stimulated B cell proliferation and IgM, IgG, and IgA secretion, whereas IL-3, IL-4, IL-5, IL-6, IFN-gamma, or GM-CSF had weak or no activity in this regard. In contrast, TGF-beta 1 was strongly inhibitory. A very strict hierarchy of cytokine interactions was found in that IL-1 was necessary to induce TNF-alpha responsiveness, and TNF-alpha the IL-2 responsiveness, of the B cells. Most likely the small number of starting B cells in the present assay (300 FACS-separated B cells/200 microliters) minimized the effects of autocrine B cell factors. IL-4 together with IL-1 induced IgE secretion, and the IgE secretion was further increased by TNF-alpha. IFN-gamma had no modulatory effect on the IL-4 dependent IgE response in this system. Pretreatment of B cells with IL-1R antagonist (IL-1ra, which binds to IL-1R) or addition of soluble TNF receptor type 1 (sTNF-R55, which binds to TNF) completely inhibited the IL-1 or TNF-alpha effects, respectively. This occurred in a specific manner; the inhibition was reversed by a large excess of cytokine. IL-1ra also inhibited a B cell response induced by PMA-preactivated EL-4 cells alone. Because B cells responding to such preactivated EL-4 cells did not acquire TNF-alpha responsiveness, no IL-1 was apparently involved under this assay condition. It appears, therefore, 1) that IL-1ra can act on B cells and 2) that this antagonist may not only block IL-1R, but may provide a direct or indirect inhibitory signal interfering even with IL-1-independent B cell activation.
Tucci
A
A
Division of Haematology, Hôpital Cantonal Universitaire, Geneva, Switzerland.
James
H
H
Chicheportiche
R
R
Bonnefoy
J Y
JY
Dayer
J M
JM
Zubler
R H
RH
D001402:B-Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D002450:Cell Communication; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D007070:Immunoglobulin A / Q000096:biosynthesis; D007073:Immunoglobulin E / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D007378:Interleukins / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic / Q000037:antagonists & inhibitors*; D017472:Receptors, Interleukin-1; D018124:Receptors, Tumor Necrosis Factor; D013945:Thymoma / Q000188:drug therapy / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D016207:Cytokines; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007378:Interleukins; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D007073:Immunoglobulin E; D016178:Granulocyte-Macrophage Colony-Stimulating Factor