Il10−/− (n = 17), Il10−/− × Gpr4−/− (n = 13), Il10−/− × Ogr1−/− (n = 10), and Il10−/− × Gpr4−/− × Ogr1−/− (n = 10) developed colitis after approximately 190 days. Here, GPR4 is linked to colitis.