title: Identification of strong interleukin-10 inducing lactic acid bacteria which down-regulate T helper type 2 cytokines.
abstract: BACKGROUND
  Decreased exposure to microbial stimuli has been proposed to be involved in the increased prevalence of atopic disease. Such a relationship was indicated by enhanced presence of typical probiotic bacteria in the intestinal flora correlating with reduced prevalence of atopic disease. Recent clinical trials suggested that probiotic bacteria may decrease and prevent allergic symptoms, but which (different) species or strains may contribute is poorly understood.
  
  
  OBJECTIVE
  We sought to select probiotic bacteria by their ability to modulate in vitro production of cytokines by peripheral blood mononuclear cells (PBMCs), to make a rational choice from available strains.
  
  
  METHODS
  PBMCs, purified monocytes, and lymphocytes from healthy donors were co-cultured with 13 different strains of probiotic bacteria. The effect of lactic acid bacteria (LAB) on different cell populations and effects on cytokine production induced by the polyclonal T cell stimulator phytohaemagglutinin (PHA) was evaluated by measuring T helper type 1, T helper type 2 (Th2), and regulatory cell cytokines in culture supernatants by multiplex assay.
  
  
  RESULTS
  PBMCs cultured with different strains produced large amounts of IL-10 and low levels of IL-12p70, IL-5, and IL-13. In PHA-stimulated PBMC cultures, the tested strains decreased the production of Th2 cytokines. Neutralizing IL-10 production resulted in partial to full restoration of Th2 cytokine production and concurred with an increase in pro-inflammatory cytokines such as IL-12p70 and TNF-alpha. Within the PBMCs, the CD14(+) cell fraction was the main source of IL-10 production upon interaction with LAB.
  
  
  CONCLUSIONS
  Our results indicate that certain strains of lactobacilli and bifidobacteria modulate the production of cytokines by monocytes and lymphocytes, and may divert the immune system in a regulatory or tolerant mode. These specific strains may be favorable to use in prevention or treatment of atopic disease.
authors.affiliation: Department of Pediatrics, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: L E M
authors.initials: LE
authors.lastname: Niers
authors.forename: H M
authors.initials: HM
authors.lastname: Timmerman
authors.forename: G T
authors.initials: GT
authors.lastname: Rijkers
authors.forename: G M
authors.initials: GM
authors.lastname: van Bleek
authors.forename: N O P
authors.initials: NO
authors.lastname: van Uden
authors.forename: E F
authors.initials: EF
authors.lastname: Knol
authors.forename: M L
authors.initials: ML
authors.lastname: Kapsenberg
authors.forename: J L L
authors.initials: JL
authors.lastname: Kimpen
authors.forename: M O
authors.initials: MO
authors.lastname: Hoekstra
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000276:immunology; D001644:Bifidobacterium / Q000276:immunology*; D002478:Cells, Cultured; D016207:Cytokines / Q000276:immunology*; D015536:Down-Regulation / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology; D016753:Interleukin-10 / Q000276:immunology*; D007378:Interleukins / Q000276:immunology; D007778:Lactobacillus / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000276:immunology; D009000:Monocytes / Q000276:immunology; D010835:Phytohemagglutinins / Q000276:immunology; D019936:Probiotics; D018418:Th2 Cells / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
chemical_list: D015703:Antigens, CD; D016207:Cytokines; D007378:Interleukins; D010835:Phytohemagglutinins; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007371:Interferon-gamma