The Role of Human Milk Oligosaccharides (hmos) in the Establishment and Proliferation of Bifidobacterium Infantis in the Infant Gut

The molecular basis by which human breast milk supports the development of a protective intestinal microbiome in infants is unknown. Human milk oligosaccharides (HMOs) are quantitatively the third largest and most diverse component of breast milk. HMOs are believed to provide protection against pathogens and prebiotic enrichment of beneficial commensals such as bifidobacteria. Bifidobacterium infantis ATCC 15697, an isolate from the infant gut, preferentially consumes four milk oligosaccharides representing nearly 70% of all HMOs present in milk. The purpose of this study was to understand the role of HMOs in establishing and promoting a Bifidobacteria‐rich gut microflora in infants. When B. infantis is pre‐grown on HMOs versus lactose, there is a two‐fold increase in its binding ability to Caco2 cells. To further understand this interaction we have measured the global changes in gene expression of Caco2 cells in the presence of HMOs and B. infantis. This approach will serve as model for understanding how nutrients in a diet (HMOs) influence the interactions between gut microbiota and epithelial cells to effect human health. Research support provided by the California Dairy Research Foundation and UC Discovery Grants.