Interleukin-10 generation in atopic children following oral Lactobacillus rhamnosus GG

Background Oral Lactobacillus rhamnosus GG ingestion for 5 days to 4 weeks has been shown to alleviate clinical symptoms of gastrointestinal inflammation and atopic dermatitis. Objective To determine whether oral Lactobacillus rhamnosus GG may act by generating immunosuppressive mediator in atopic children. Methods Lactobacillus rhamnosus GG (ATCC 53103) at a daily dose of 2 x 10(10) cfu was added for 4 weeks to the diets of nine children (mean age, 21 months) with atopic dermatitis. Blood and faecal samples were collected before supplementation and at early (2 weeks) and late stage (4 and 8 weeks from the beginning). The concentrations of interleukin-6 (IL-6), IL-10, IL-12, tumour necrosis factor-alpha (TNF alpha) and interferon-gamma (IFN gamma) in sera, as well as the production of IL-2, IL-4, IL-10 and IFN gamma in mitogen-induced peripheral blood mononuclear cells, were assessed. Secretory IgA and TNF alpha were also determined in faeces. Results The serum IL-10 concentration differed significantly between before, early and late samples (P < 0.001) due to the elevation of serum IL-10 in the later phase of oral Lactobacillus rhamnosus GG ingestion. The enhancement of IL-10 production in mitogen-induced cultures preceded the rise in serum IL-10. Conclusion The enhanced IL-10 generation in vivo substantiates the anti-inflammatory properties of specific probiotic bacteria strains, and provides an additional reason for considering such treatments for patients with intestinal inflammation.