# A unique blend of five human milk oligosaccharides supports recovery of infant microbiome composition and function after ex vivo antibiotic use

## TL;DR

A mix of five human milk sugars helps restore a baby's gut microbes and fights harmful bacteria after antibiotic use.

## Contribution

Demonstrates that a specific blend of five HMOs can restore microbiome function and inhibit pathogens after antibiotic exposure.

## Key findings

- The HMO blend supports beneficial gut microbes in an ex vivo infant gut model.
- The HMO blend reduces pathogen adhesion to intestinal cells in vitro.
- The HMOs act through multiple mechanisms to shape microbiota and prevent microbial pathogenesis.

## Abstract

Human milk oligosaccharides (HMOs) are the third most abundant solid component of human breast milk, with well-established prebiotic and immunomodulatory functions. HMOs serve as selective substrates to support the growth of beneficial microbes in the developing gastrointestinal tract. At the same time individual HMOs have been shown to also exert selection against pathogens via direct anti-adhesive mechanisms. A longstanding hypothesis has held that HMOs act in concert and with other bioactive components of milk, and that this complex matrix of milk components collectively accounts for both the benefits to microbiome development and reduced risk of infectious disease associated with breastfeeding. The prebiotic activity of a diverse blend of fucosylated, acetylated, and sialylated HMOs was examined using microbiota cultured in an ex vivo model of the infant gastrointestinal tract before, during and after the supplementation of common childhood antibiotics. The anti-adhesive activity of this blend against infant-prevalent bacterial pathogens was tested using in vitro cultured intestinal epithelial cells. Taken together, this data suggests that a blend of 5 specific HMOs acts through multiple selection mechanisms to shape the development of the microbiota and interrupt opportunistic microbial pathogenesis.