Leukotriene B4 up-regulates IL-6 rather than IL-1 synthesis in human monocytes.
Leukotriene B4 (LTB4) preferentially induced IL-6 mRNA accumulation and IL-6 protein release as assessed by ELISA and the B9 cell bioassay. In contrast, minimal IL-1 mRNA or protein was induced by LTB4 either in the absence or presence of muramyl dipeptide. Supernatants of LTB4-treated monocytes consistently showed enhanced thymocyte costimulatory activity and this was abrogated by 75-80% by anti-IL-1 antibody. Baseline production of IL-1 appeared however to be sufficient for a synergistic stimulation of thymocytes in the presence of IL-6. Our results now help clarify that LTB4 stimulated preferentially IL-6 production and that the observed LTB4-induced augmentation in thymocyte responses to monocyte supernatants is due to augmented IL-6 contents in the presence of baseline minimal IL-1 production.
Poubelle
P E
PE
Unité de Recherche Inflammation et Immunologie-Rhumatologie, Centre de Recherche du CHUL, Boul Laurier, Québec, Canada.
Stankova
J
J
Grassi
J
J
Rola-Pleszczynski
M
M
D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000494:pharmacology; D015152:Blotting, Northern; D002455:Cell Division / Q000187:drug effects; D006801:Humans; D006825:Hybridomas / Q000378:metabolism; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000096:biosynthesis*; D015850:Interleukin-6 / Q000096:biosynthesis*; D007975:Leukotriene B4 / Q000502:physiology*; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects*
D007375:Interleukin-1; D015850:Interleukin-6; D012333:RNA, Messenger; D007975:Leukotriene B4; D000119:Acetylmuramyl-Alanyl-Isoglutamine