Treating Disease with Worms

+ See all authors and affiliations

Science  07 Jan 2005:
Vol. 307, Issue 5706, pp. 18
DOI: 10.1126/science.307.5706.18b

Crohn's disease is a debilitating inflammatory condition of the intestine. Although the etiology is unclear, the disease is thought to result from inappropriate activation of the immune system against the bacterial flora of the gut. In developing countries, where infection with parasitic intestinal helminths is widespread, Crohn's disease is rare, leading to the notion that the allergic-like state generated by parasitic worms counteracts proinflammatory influences.

To test this, Summers et al. fed Crohn's patients eggs of the common pig helminth Trichuris suis, which can colonize the human intestine for short periods without pathology. A marked improvement was seen in most of the patients, and these clinical results are paralleled by the observations of Elliott et al., who found that giving the helminth Heligmosomoides polygyrus to mice that were afflicted with a Crohn's-like condition reversed inflammation. In protected animals, there was a redress of the imbalance toward proinflammatory cytokines, and these early results suggest that unconventional therapy of this type might be effective in treating a range of chronic inflammatory diseases that extend beyond the gut. — SJS

Gut 54, 87 (2005); Eur. J. Immunol. 34, 2690 (2004).

Navigate This Article