Human Milk Oligosaccharides and Synthetic Galactosyloligosaccharides Contain 3'-, 4-, and 6'-Galactosyllactose and Attenuate Inflammation in Human T84, NCM-460, and H4 Cells and Intestinal Tissue Ex Vivo.
BACKGROUND
The immature intestinal mucosa responds excessively to inflammatory insult, but human milk protects infants from intestinal inflammation. The ability of galactosyllactoses [galactosyloligosaccharides (GOS)], newly found in human milk oligosaccharides (HMOS), to suppress inflammation was not known.


OBJECTIVE
The objective was to test whether GOS can directly attenuate inflammation and to explore the components of immune signaling modulated by GOS.


METHODS
Galactosyllactose composition was measured in sequential human milk samples from days 1 through 21 of lactation and in random colostrum samples from 38 mothers. Immature [human normal fetal intestinal epithelial cell (H4)] and mature [human metastatic colonic epithelial cell (T84) and human normal colon mucosal epithelial cell (NCM-460)] enterocyte cell lines were treated with the pro-inflammatory molecules tumor necrosis factor-α (TNF-α) or interleukin-1β (IL-1β) or infected with Salmonella or Listeria. The inflammatory response was measured as induction of IL-8, monocyte chemoattractant protein 1 (MCP-1), or macrophage inflammatory protein-3α (MIP-3α) protein by ELISA and mRNA by quantitative reverse transcriptase-polymerase chain reaction. The ability of HMOS or synthetic GOS to attenuate this inflammation was tested in vitro and in immature human intestinal tissue ex vivo.


RESULTS
The 3 galactosyllactoses (3'-GL, 4-GL, and 6'-GL) expressed in colostrum rapidly declined over early lactation (P < 0.05). In H4 cells, HMOS attenuated TNF-α- and IL-1β-induced expression of IL-8, MIP-3α, and MCP-1 to 48-51% and pathogen-induced IL-8 and MCP-1 to 26-30% of positive controls (P < 0.001). GOS reduced TNF-α- and IL-1β-induced inflammatory responses to 25-26% and pathogen-induced IL-8 and MCP-1 to 36-39% of positive controls (P < 0.001). GOS and HMOS mitigated nuclear translocation of nuclear transcription factor κB (NF-κB) p65. HMOS quenched the inflammatory response to Salmonella infection by immature human intestinal tissue ex vivo to 26% and by GOS to 50% of infected controls (P < 0.01).


CONCLUSION
Galactosyllactose attenuated NF-κB inflammatory signaling in human intestinal epithelial cells and in human immature intestine. Thus, galactosyllactoses are strong physiologic anti-inflammatory agents in human colostrum and early milk, contributing to innate immune modulation. The potential clinical utility of galactosyllactose warrants investigation.
['Newburg|David S|DS|http://orcid.org/0000-0001-6042-7303', 'Ko|Jae Sung|JS|', 'Leone|Serena|S|', 'Nanthakumar|N Nanda|NN|']
D000818:Animals D000893:Anti-Inflammatory Agents D002460:Cell Line D003106:Colon D003126:Colostrum D016207:Cytokines D005260:Female D006801:Humans D007249:Inflammation D018836:Inflammation Mediators D007413:Intestinal Mucosa D007774:Lactation D007785:Lactose D008087:Listeria D051379:Mice D008895:Milk, Human D009844:Oligosaccharides D011247:Pregnancy D012475:Salmonella D012480:Salmonella Infections D015398:Signal Transduction D014312:Trisaccharides
Human milk oligosaccharides galactosyllactose colostrum enteric infection human intestinal epithelium mucosal immune response