Human milk oligosaccharides influence maturation of human intestinal Caco-2Bbe and HT-29 cell lines

Stimulation of gastrointestinal tract maturation is 1 of the many benefits of human milk. Human milk oligosaccharides (HMOs) are abundant in human milk and are reported to promote enterocyte differentiation in vitro. The objective of this study was to assess the impact of 3 predominant HMOs on multiple aspects of enterocyte maturation in vitro. Ranging from crypt-like to differentiated enterocytes, we used the well-characterized intestinal cell lines HT-29 and Caco-2Bbe to model early and late stages of differentiation, respectively. With this model of the crypt-villus axis made up of preconfluent HT-29, preconfluent Caco-2Bbe, and postconfluent Caco-2Bbe cultures, we characterized the impact of lacto-N-neotetraose (LNnT), 2'-fucosyllactose (2'FL), and 6'-sialyllactose on epithelial cell kinetics and function. All 3 HMOs dose-dependently inhibited cell proliferation in undifferentiated HT-29 and Caco-2Bbe cultures (P < 0.05). In contrast to previous reports, only treatment with 2'FL at concentrations similar to human milk increased alkaline phosphatase activity by 31% (P = 0.044) in HT-29 cultures and increased sucrase activity by 54% (P = 0.005) in well-differentiated Caco-2Bbe cultures. LNnT at concentrations similar to that reported for human milk increased transepithelial resistance by 21% (P = 0.002) in well-differentiated Caco-2Bbe cells. In summary, all 3 HMOs reduced cell proliferation in an epithelial cell model of the crypt-villus axis. However, effects on differentiation, digestive function, and epithelial barrier function differed between the HMOs tested. These results suggest differential roles for specific HMOs in maturation of the gastrointestinal tract.