AIM:To explore the pathophysiological significance of delayedtype hypersensitivity(DTH)reaction in mouse gastrointestinaltract induced by an allergen 2,4-dinitrochlorobenzene(DNCB).METHODS:BALB/c mice were randomly divided intocontrol and DTH1-6groups.After sensitized by DNCBsmeared on the abdominal skin,the mice were challengedwith DNCB by gavage or enema.The weight,stool viscosityand hematochezia were observed and accumulated asdisease active index(DAI)score;the gastrointestinalmotility was represented by active charcoal propulsion rate;the colon pathological score was achieved by macropathologyand HE staining of section prepared for microscopy;andthe leukocyte migration inhibitory factor(LMIF)activity wasdetermined by indirect capillary assay of the absorbance(A)of migrated leukocytes.RESULTS:Active charcoal propulsion rates of smallintestine in the DNCB gavages groups were significantlyhigher than that in the control group(P<O.01).The DAIscores and pathological score in DNCB enema groups werealso higher than that in the control group(P<0.05),andthere were significant rises in LMIF activity in DNCB enemagroups as compared with control groups(P<0.01).CONCLUSION:Mouse gastrointestinal DTH reaction couldbe induced by DNCB,which might facilitate the mechanismunderlying the ulcerative colitis.