Prestimulation with KGF had no effect on IL-1-induced IL-8 secretion in Caco-2 cells. The Caco-2 cells were cultured for 24 h as in Fig. 1. Then, the supernatants were removed (at −24 h) and 100 ng/ml rhKGF was added to the KGF prestimulation wells, or an equivalent amount of FBS-RPMI was added to all others. After incubation for 24 h, all supernatants were removed and replaced with 10% FBS-RPMI either with or without rhKGF at 100 ng/ml and/or rhIL-1β at 0.5 ng/ml, as indicated (time 0 h). The cells were incubated for an additional 24 h, then, the supernatants were collected for determination of IL-8 levels. Shown are the mean ± SEM of three separate experiments. Bars indicate the significance compared between appropriate conditions.