Some helminths have been known to have a treatment effect in inflammatory bowel diseases, including Crohn’s disease (CD); however, live parasite therapy can cause unwanted side effects. To develop a safe therapeutic, we investigated the preventive or therapeutic potential of proteins from the third stage larva of A. simplex in a mouse model. We also analyzed the cytokine profile from splenic and mesenteric lymph node lymphocytes to elucidate the underlying immunological mechanism.

CD was induced in mice with DSS, and the effect of an A. simplex larval protein on CD was assessed. A change in body weight and DAI (disease activity index) were observed in mice. The expression levels of cytokines from mesenteric lymph nodes (MLN) compared to splenic lymphocytes were measured with ELISA.

Peritoneal administration of preventive and therapeutic A. simplex larval proteins attenuated DSS-induced CD by a reduction of the DAI and weight loss. A shortening of colon length was more definitely observed in the therapeutic group than in the preventive group. The cytokine expression levels were more obvious in lymphocytes from mesenteric lymph nodes than from splenic lymphocytes.

Taken together, these results suggest that A. simplex proteins can change cytokine profiles and may have a preventive effect in DSS-induced CD mice.