TITLE:
Human Milk Oligosaccharides Enhance Innate Immunity to Respiratory Syncytial Virus and Influenza in Vitro
AUTHORS:
Geralyn Duska-McEwen, Albert P. Senft, Teah L. Ruetschilling, Edward G. Barrett, Rachael H. Buck
KEYWORDS:
Human Milk Oligosaccharides, Respiratory Syncytial Virus, Influenza Virus, Inflammation, Innate Immunity
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.5 No.14,
August
15,
2014
ABSTRACT: Human
milk oligosaccharides (HMO) contribute to innate immunity by enhancing growth
of beneficial bacteria, epithelial cell maturation and mucosal barrier
integrity. They have immunomodulatory effects and can block pathogen binding
to host cell surface glycans or receptors. We investigated the effects of
2’-fucosyllactose (2’FL), 6’-sialyllactose (6’SL), 3’-sialyllactose (3’SL) and
lacto-N-neoTetraose (LNnT) on human respiratory epithelial cell lines or
peripheral blood mononuclear cells (PBMCs) following respiratory viral
infectionin vitro. Expression of
cytokines and viral load were monitored in infected cells. These biomarkers of
innate immunity were selected since viral load and cytokine levels (IP-10,
MIP-1α, IL-6, IL-8, TNF-α) have been correlated with disease
severity in respiratory syncytial virus (RSV) and influenza (IAV) virus infectionin vivo. 2’FL significantly decreased
RSV viral load and cytokines associated with disease severity (IL-6, IL-8,
MIP-1α) and inflammation (TNF-α, MCP-1) in airway epithelial cells.
LNnT and 6’SL significantly decreased IAV viral load in airway epithelial
cells. 6’SL dose-dependently down-regulated IP-10 and TNF-α in RSV infected PBMCs. HMO at or below levels found in breast
milk enhance innate immunity to respiratory viruses in vitro and may interact directly with cells to modulate biomarkers
of innate immunity.