Dexamethasone suppresses concanavalin A-induced production of chemotactic lymphokines by releasing a soluble factor from splenic T lymphocytes.
Treatment of guinea-pig spleen cells with glucocorticoids, such as dexamethasone (DEX), reduces concanavalin A (Con A)-induced production of chemotactic lymphokines (CLK), such as eosinophil chemotactic factor and macrophage chemotactic factor. The decreased CLK production is not caused by a direct effect of DEX on the spleen cells producing CLK, because Con A-induced CLK production is suppressed when the cells are cultured together with cell-free culture supernatants of the spleen cells which had been pretreated with DEX. A soluble suppressive factor, termed CLK-SF, with a MW of about 20,000, seems to be responsible for the suppression of both CLK production. CLK-SF is produced from DEX-treated T lymphocytes. CLK-SF probably exerts a critical role in the early stage of CLK production. In contrast, CLK-SF fails to inhibit Con A-induced lymphocyte proliferation, although DEX itself suppresses lymphocyte proliferation. This suggests that DEX suppresses Con A-induced CLK production by a different mechanism from that for lymphocyte proliferation.
D000818:Animals; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000096:biosynthesis*; D002631:Chemotactic Factors, Eosinophil / Q000096:biosynthesis; D003208:Concanavalin A / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology*; D006168:Guinea Pigs; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000096:biosynthesis; D008264:Macrophages; D008938:Mitosis / Q000187:drug effects; D008970:Molecular Weight; D013154:Spleen / Q000276:immunology; D013491:Suppressor Factors, Immunologic; D013601:T-Lymphocytes / Q000276:immunology*; D013997:Time Factors
D002630:Chemotactic Factors; D002631:Chemotactic Factors, Eosinophil; D008222:Lymphokines; D013491:Suppressor Factors, Immunologic; D003208:Concanavalin A; D003907:Dexamethasone