Human recombinant IL-4 induces activated B lymphocytes to produce IgG and IgM.
In this report, we describe a novel biologic activity of IL-4 namely, its ability to induce activated human B cells to produce IgM. Staphylococcus aureus Cowan I-activated blasts prepared from high density tonsil B cells were found to secrete IgG and IgM, but no IgE, when cultured in the presence of rIL-4. The differentiating activity of rIL-4 was totally blocked by a neutralizing anti-IL-4 antiserum, therefore demonstrating that the IgG/IgM-inducing activity of rIL-4 was an intrinsic property of IL-4. rIL-4 was only minimally inducing Ig production of blasts prepared from low density B cells, whereas it induced B cell blasts prepared from high density B cells to secrete a high amount of Ig. Delayed additions of the neutralizing anti-IL-4 antiserum demonstrated that a 48-h contact between IL-4 and B cell blasts was required for optimal Ig production. The IL-4-mediated IgG and IgM production was neither suppressed by IFN-gamma nor by anti-CD23 mAb 25, whereas these agents have been shown earlier to inhibit IgE production of enriched B cells cultured in the presence of IL-4. These data indicate that the IgG/IgM-inducing activity of IL-4 is not regulated like the IL-4-induced IgE production by enriched B cells.
Defrance
T
T
UNICET, Laboratory for Immunological Research, Dardilly, France.
Vanbervliet
B
B
Pène
J
J
Banchereau
J
J
D000911:Antibodies, Monoclonal / Q000502:physiology; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D001667:Binding, Competitive; D006801:Humans; D007106:Immune Sera / Q000494:pharmacology; D007074:Immunoglobulin G / Q000096:biosynthesis*; D007075:Immunoglobulin M / Q000096:biosynthesis*; D007371:Interferon-gamma / Q000494:pharmacology; D015847:Interleukin-4; D007378:Interleukins / Q000276:immunology / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D009500:Neutralization Tests; D011961:Receptors, Fc / Q000276:immunology; D017455:Receptors, IgE; D011994:Recombinant Proteins / Q000494:pharmacology; D013209:Staphylococcal Vaccines
D000911:Antibodies, Monoclonal; D000944:Antigens, Differentiation, B-Lymphocyte; D007106:Immune Sera; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007378:Interleukins; D011961:Receptors, Fc; D017455:Receptors, IgE; D011994:Recombinant Proteins; D013209:Staphylococcal Vaccines; D015847:Interleukin-4; D007371:Interferon-gamma