Glycan-modifying bacteria-derived soluble factors from Bacteroides thetaiotaomicron and Lactobacillus casei inhibit rotavirus infection in human intestinal cells.

Rotaviruses attach to intestinal cells in a process that requires glycan recognition. Some bacteria from the gut microflora have been shown to modify cell-surface glycans. In this study, human intestinal cultured cells were incubated with bacteria-derived soluble factors and infected with rotavirus. Results show that only bacterial soluble factors that increase cell-surface galactose namely, those of Bacteroides thetaiotaomicron and Lactobacillus casei were able to efficiently block rotavirus infections. Increasing cell-surface galactose using galactosyltransferase resulted in a similar blockage of rotavirus infections. These results indicate that manipulation of cell-surface intestinal glycans by bacterial soluble factors can prevent rotavirus infection in a species-specific manner, and should now be considered a potential therapeutic approach against rotavirus infection.