The Human Milk Oligosaccharides 3-FL, Lacto-N-Neotetraose, and LDFT Attenuate Tumor Necrosis Factor-α Induced Inflammation in Fetal Intestinal Epithelial Cells In Vitro through Shedding or Interacting with Tumor Necrosis Factor Receptor 1

Abstract

Scope: Human milk oligosaccharides (hMOs) can attenuate inflammation by modulating intestinal epithelial cells, but the mechanisms of action are not well-understood. Here, the effects of hMOs on tumor necrosis factor-α (TNF-α) induced inflammatory events in gut epithelial cells are studied.

Methods and results: The modulatory effects of 2'-fucosyllactose, 3-fucosyllactose (3-FL), 6'-sialyllactose, lacto-N-tetraose, lacto-N-neotetraose (LNnT), lactodifucotetraose (LDFT), and lacto-N-triaose (LNT2) on immature (FHs 74 Int) and adult (T84) intestinal epithelial cells with or without TNF-α are determined. Interleukin-8 (IL-8) secretion in FHs 74 Int and T84 are quantified to determine hMO induced attenuation of inflammatory events by ELISA. 3-FL, LNnT, and LDFT significantly attenuate TNF-α induced inflammation in FHs 74 Int, while LNT2 induces IL-8 secretion in T84. In addition, microscale thermophoresis assays and ELISA are used to study the possible mechanisms of interaction between effective hMOs and tumor necrosis factor receptor 1 (TNFR1). 3-FL, LNnT, and LDFT exert TNFR1 ectodomain shedding while LNnT also shows binding affinity to TNFR1 with a Kd of 900 ± 660 nM.

Conclusion: The findings indicate that specific hMO types attenuate TNF-α induced inflammation in fetal gut epithelial cells through TNFR1 in a hMO structure-dependent fashion suggest possibilities to apply hMOs in management of TNF-α dependent diseases.

Keywords: human milk oligosaccharides; inflammation; intestinal epithelial cells; tumor necrosis factor receptors; tumor necrosis factor-α.