Intimate gut interactions: helminths and the microbiota

Abstract

Changing exposure to intestinal helminths, or alterations in our intestinal microbiome, have been independently proposed to underlie the increasing incidence of chronic inflammatory diseases including allergy, autoimmunity and inflammatory bowel disease (IBD) observed in developed nations. A recent study in Science links these findings by showing that intestinal helminth infection can prevent the outgrowth of a common intestinal bacterium that causes IBD in genetically susceptible mice.

Figure 1

(A) Nod2^−/− mice exhibit low goblet cell numbers and an outgrowth of the intestinal bacterium Bacteriodes vulgatus, and develop intestinal inflammation. (B) Infection of Nod2^−/− mice with an intestinal helminth (Trichuris muris or Heligmosomoides polygyrus) elicits host type 2 immunity, leading to increased goblet cell numbers, mucous production and an expansion of intestinal bacteria belonging to the Clostridiales family. The outgrowth of Clostridiales species in turn suppresses the growth of Bacteriodes vulgatus and prevents intestinal inflammation.