HISTAMINE INDUCES INTERLEUKIN-8 SECRETION BY ENDOTHELIAL-CELLS

It has been shown that histamine induces early changes on endothelial cells (EC), such as a transient expression of P-selectin and secretion and/or surface expression of early mediators (eg, prostacyclin [PG1(2 )], platelet-activating factor [PAF], and leukotriene B-4 [LTB(4)]). H owever, delayed effects of histamine on EC and particularly on cytokin e production are undefined. In this study, the effect of histamine on interleukin (IL)-8 production by EC was evaluated using an enzyme-link ed immunosorbent assay (ELISA) method and mRNA expression. The results showed that histamine increased the secretion and the mRNA expression of IL-8 by EC. Histamine-induced IL-8 production was (1) dose-depende nt (at a dose greater than or equal to 10(-6) mol/L), (2) potentialize d by costimulation with tumor necrosis factor (TNF)-alpha, (3) inhibit ed by H1 or H2 histamine receptor antagonists, and (4) significantly i ncreased 4 hours after the initial stimulation. These data suggest tha t histamine may be involved in the control of the late inflammatory re action associated to allergic disorders through IL-8 secretion by EC. (C) 1994 by The American Society of Hematology.