Will worms really cure Crohn's disease?

Abstract

In conclusion, helminth infection provides us with an excellent model of a successful parasite which is able to manipulate its environment within the host to its advantage. Summers and colleagues have now taken that further by using helminths to gain an advantage for the host. It is too early to determine whether this form of treatment will be safe and effective for larger numbers of patients with IBD-further controlled randomised studies will be required to answer this. However, what these important and innovative studies demonstrate is the need for a greater understanding of the helminth-host relationship. This is slowly being addressed but almost exclusively in animal models. Of special interest will be identification of antigens or epitopes responsible for the generation of a tolerant environment, and recent work indicates that one candidate is the schistosome oligosaccharide lacto-N-neotetraose. This molecule, which is also present in human milk, stimulates the expansion of a Gr1 + cell population, which creates a Th2 biased immune environment by increased production of IL-10 and TGF-β, and by directing naïve CD4+ T cells down the Th2 path. Molecules such as this may represent potentially novel therapeutic agents for chronic inflammatory disorders such as IBD, and thus bypass the need for helminth inoculation and infection.