Galectin-9 induced by dietary synbiotics is involved in suppression of allergic symptoms in mice and humans

Allergy. 2012 Mar;67(3):343-52. doi: 10.1111/j.1398-9995.2011.02771.x. Epub 2012 Jan 9.


Background: Prebiotic galacto- and fructo-oligosaccharides (scGOS/lcFOS) resembling non-digestible oligosaccharides in human milk reduce the development of atopic disorders. However, the underlying mechanisms are still unclear. Galectins are soluble-type lectins recognizing β-galactoside containing glycans. Galectin-9 has been shown to regulate mast cell degranulation and T-cell differentiation. In this study, the involvement of galectin-9 as a mechanism by which scGOS/lcFOS in combination with Bifidobacterium breve M-16V protects against acute allergic symptoms was investigated.

Methods: Mice were sensitized orally to whey, while being fed with a diet containing scGOS/lcFOS and Bifidobacterium breve M-16V (GF/Bb) or a control diet. Galectin-9 expression was determined by immunohistochemistry in the intestine and measured in the serum by ELISA. T-cell differentiation was investigated in the mesenteric lymph nodes (MLN) as well as in galectin-9-exposed peripheral blood mononuclear cells (PBMC) cultures. Sera of the mice were evaluated for the capacity to suppress mast cell degranulation using a RBL-2H3 degranulation assay. In addition, in a double-blind, placebo-controlled multicenter trial, galectin-9 levels were measured in the sera of 90 infants with atopic dermatitis who received hydrolyzed formulae with or without GF/Bb.

Results: Galectin-9 expression by intestinal epithelial cells and serum galectin-9 levels were increased in mice and humans following dietary intervention with GF/Bb and correlated with reduced acute allergic skin reaction and mast cell degranulation. In addition, GF/Bb enhanced T(h)1- and T(reg)-cell differentiation in MLN and in PBMC cultures exposed to galectin-9.

Conclusions: Dietary supplementation with GF/Bb enhances serum galectin-9 levels, which associates with the prevention of allergic symptoms.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bifidobacterium
  • Cell Degranulation
  • Cell Differentiation
  • Dermatitis, Atopic / immunology
  • Dermatitis, Atopic / prevention & control
  • Dermatitis, Atopic / therapy*
  • Dietary Supplements
  • Double-Blind Method
  • Epithelial Cells / metabolism
  • Galectins / blood
  • Galectins / metabolism*
  • Galectins / therapeutic use
  • Humans
  • Infant Formula / administration & dosage*
  • Infant Formula / chemistry
  • Intestines / cytology
  • Mast Cells / physiology
  • Mice
  • Oligosaccharides / administration & dosage*
  • Oligosaccharides / chemistry
  • Prebiotics
  • Probiotics / administration & dosage*
  • Synbiotics*
  • T-Lymphocytes / immunology
  • Treatment Outcome


  • Galectins
  • Oligosaccharides
  • Prebiotics