The role of the blood group-related glycosyltransferases FUT2 and B4GALNT2 in susceptibility to infectious disease.

The glycosylation profile of the gastrointestinal tract is an important factor mediating host-microbe interactions. Variation in these glycan structures is often mediated by blood group-related glycosyltransferases, and can lead to wide-ranging differences in susceptibility to both infectious- as well as chronic disease. In this review, we focus on the interplay between host glycosylation, the intestinal microbiota and susceptibility to gastrointestinal pathogens based on studies of two exemplary blood group-related glycosyltransferases that are conserved between mice and humans, namely FUT2 and B4GALNT2. We highlight that differences in susceptibility can arise due to both changes in direct interactions, such as bacterial adhesion, as well as indirect effects mediated by the intestinal microbiota. Although a large body of experimental work exists for direct interactions between host and pathogen, determining the more complex and variable mechanisms underlying three-way interactions involving the intestinal microbiota will be the subject of much-needed future research.