CXCL8 and colitis: To determine which specific cytokines respond to TNBS-induced injury in the zebrafish intestine, we measured mRNA expression of the pro-inflammatory cytokines, IL-1beta, IL-8, TNFalpha and the anti-inflammatory cytokine IL-10, as has been reported in mice with TNBS-induced colitis [12] and in zebrafish with chemical enterocolitis [14,18].