Worms and The Treatment of IBD

This particle article was my favorite of the Inflammatory Bowel Disease (IBD) lists because throughout the years, the usage of parasitic worms in either weight loss and prevention and/or suppression of a disease has been circulating the news. This review article will focus on a specific parasitic worm, known as Helminth, and how its derived molecules and assist in the treatment of IBD.

The two major diseases that are associated with IBD is Crohn's disease and Ulcerative colitis. Crohn's disease would affect the intestines but may also occur anywhere from the mouth to the anus and can cause a malabsorption of nutrients while ulcerative colitis affects the lining of the large intestine and rectum causing inflammation. One major point to take away from this article would be that genetic factors and environmental factos both contribute to the damaging muscosal immune response which would open the door for the introduction of the Hygiene Hypothesis. The Hygiene Hypothesis for IBD suggests that the lack of exposure to infectious agents, such as helminth, as a result of improved living standards and medical conditions which modulates the development of the immune system and increase the risk of immune disease. The major cause in low-incidence areas are a change in the lifestyle and one way to view this change would be looking at the socioeconomic level. IBD is seen more in patients that have a higher socioeconomic status due to their beter sanitation conditions. The second factor that supports the hygiene hypothesis would be the inverse relationship between infant mortality rates and the incidence of IBD. 

Gastrointestinal inflammation during Crohn's disease is Th1 mediated. The second type are the Th2 cells that enhance the elimination of the parasitic helminth infections and supports allergic responses. According to the article, the host brings about a strong Th2 immune response to provide protection against the worm colonization. The last would be the Th17 cells which are critical for the development of inflammation while the Treg cells help in the prevention of autoimmune diseases including the inhibition of IBD. On a side note, worms can be used to down-regulate the immune response! Surprisingly, Helminth colonize more than a third of the worlds population which is why using a geographical distribution to demonstrate the prevalence of Helminth is beneficial. This parasitic worm is common in developing countries and there is an inverse relationship between frequency of the worm colonization and the prevalence of IBD. 

Since there is no such thing as a perfect medication, as far as I know of that does not have any side-effects, the treatment of patients with living Helminths had some drawbacks. Some of those drawbacks was that the parasite did not stay were it was suppose to be. Here is an example: a Crohn's disease patient was given five oral doses of Trichuris suis which caused an infection in the ileocecal regions and found a sexually mature male worm within the cecum. This can also result in diarrhea and abdominal cramps. Luckily, Helminth-derived immunomodulatory molecules can contribute to the anti-colitis effect without the helminth infection. To summarize this article up, helminth-derived molecules hope to be effective in the treatment of the IBD without having to worry about having the parasite living inside the individual. 

References:
1. Ruyssers, Nathalie, De Winter, Benedicte, De Man, Joris G., Loukas, Alex, Herman, Arnold G., Pelckmans, Paul A., and Moreels, Tom G.. "Worms and the Treatment of Inflammatory Bowel Disease: Are Molecules the Answer?." 2008 March 5. Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology, University of Antwerp, Division of Infectious Diseases, Queensland Institute of Medical reseach, Laboratory of Pharmacology, University of Antwerp, and Division of Gastroenterology and Hepatology, University of Antwerp.