This study evaluates the effects of intrapleural (i.pl.) injection of interleukin (IL-6) and IL-10 and their specific antibodies on the early (4 h) and late (48 h) inflammatory responses caused by carrageenan (Cg) injected into the mouse pleural cavity. The i.pl. injection of IL-6, 5 min prior to Cg, reduced in a dose-dependent and significant manner, the exudation and total and differential leukocyte migration according to assessment in both the early (4 h) and the late (48 h) phases of Cg inflammatory response (P<0.01). Intrapleural injection of IL-10, 5 min prior to i.pl. injection of Cg, resulted in a significant inhibition of the early phase (4 h) (P<0.01), but had no significant effect in relation to the late (48 h) phase of Cg response. The antibodies anti-IL-6 (given i.pl. 30 min prior to Cg) caused a significant decrease in both total and differential leukocyte influx, but significantly increased exudation according to assessment 4 h after pleurisy induction by Cg (P<0.01). In contrast, anti-IL-10 antibody caused graded and marked increase of both total and differential leukocyte influx and also increased fluid leakage as assessed 4 h after Cg injection (P<0.01). In the late phase (48 h) these antibodies increased the inflammatory parameters (anti-IL-6) studied or had no effect (anti-IL-10). Taken together, the current results confirm and extend previous data from the literature by showing that IL-6 and IL-10 regulate several signs of inflammatory response, here characterized by marked inhibition of polymorphonuclear cell influx and blockage of fluid leakage to the site of Cg-induced pleurisy in the mouse.
Copyright 2002 Elsevier Science Ltd.