Glucocorticosteroid-dependent synergy between interleukin 1 and interleukin 6 for human B lymphocyte differentiation.
In order to analyze the effects of interleukin (IL) 6 on human in vitro Ig production B lymphocytes were activated by Staphylococcus aureus Cowan strain I (SAC) in the presence of low concentrations of IL2 (1 U/ml) and dexamethasone (10(-7) M). Previously we showed that this model of B cell response is completely monocyte dependent. We here demonstrate that, under these experimental conditions, IL6 is able to replace monocytes and stimulate Ig production provided IL1 is also present. Dose-effect curves show that these two monokines act synergistically. This synergy is demonstrable only in the presence of dexamethasone, when B lymphocytes are activated (by SAC) and when T cell help (provided by IL2) is present. It results in the production of both IgM and IgG. Both IL1 and IL6 have to be present during the first 48 h of culture to exert an optimal effect. These results show that IL6 may act on early (as well as on late) stages of normal B lymphocyte differentiation. Moreover, glucocorticosteroids potentiate the synergistic effect of IL1 and IL6 on their B lymphocyte target, an effect comparable to that exerted on hepatocytes.
Emilie
D
D
INSERM U 131, Clamart, France.
Crevon
M C
MC
Auffredou
M T
MT
Galanaud
P
P
D001402:B-Lymphocytes / Q000166:cytology*; D001685:Biological Factors / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis; D007075:Immunoglobulin M / Q000096:biosynthesis; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000494:pharmacology*; D015850:Interleukin-6; D007378:Interleukins / Q000494:pharmacology*; D015846:Monokines
D001685:Biological Factors; D005938:Glucocorticoids; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007375:Interleukin-1; D015850:Interleukin-6; D007378:Interleukins; D015846:Monokines