E. histolytica-derived secretory product (SP)-induced IL-8 production in HMC-1 cells occurs through a protease-activated receptor 2 (PAR2) or ROS-independent mechanism. (A) The effect of anti-PAR2 on SP-stimulated IL-8 production. (n = 4) (B) The effect of SPs on induction of ROS generation at 30 min in HMC-1 cells. (n = 3). All reactions were performed in triplicate measurements of each experiment. Data are presented as the mean ± SEM of at least three independent experiments. The asterisks indicate the result of comparisons with the control (*p < 0.05).