title: Differential effects of lactobacilli on activation and maturation of mouse dendritic cells.
abstract: Lactic acid bacteria (LAB) are of interest because of their potential to modulate immune responses. The effects of LAB range from regulation to stimulation of the immune system. A series of studies were performed in vitro to study the effects of six lactic acid bacteria (LAB), Lactobacillus helveticus LH-2, Lactobacillus acidophilus La-5, La-115, La-116 and La-14, and Lactobacillus salivarius, on maturation and activation of mouse dendritic cells. Production of tumour necrosis factor (TNF)-?, interleukin (IL)-6 and IL-10 by dendritic cells (DCs) was determined after treating cells with live LAB. The expression of DC maturation markers, CD80 and CD40, was also measured using flow cytometry after stimulation with LAB. In addition, the expression of Toll-like receptors (TLRs) 2, 4 and 9 by DCs stimulated with LAB was measured. Our results revealed that LAB act differentially on pro-inflammatory and anti-inflammatory cytokine production and induction of co-stimulatory molecules by DCs. Specifically, L. salivarius was found to be the most effective LAB to induce pro-inflammatory cytokine production and expression of co-stimulatory molecules. Moreover, La-14, La-116 and La-5 induced moderate maturation and activation of DCs. On the other hand, LH-2 and La-115 were the least effective lactobacilli to induce DC responses. The present study also revealed that L. salivarius was able to induce the expression of TLR2, 4 and 9 by DCs. In conclusion, various strains and species of LAB can differentially regulate DC activation and maturation, providing further evidence that these bacteria may have the ability to influence and steer immune responses in vivo.
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, 419 Gordon Street, Guelph, Ontario, N1G 2W1 Canada.
authors.forename: I
authors.initials: I
authors.lastname: Elawadli
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, 419 Gordon Street, Guelph, Ontario, N1G 2W1 Canada.
authors.forename: J T
authors.initials: JT
authors.lastname: Brisbin
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, 419 Gordon Street, Guelph, Ontario, N1G 2W1 Canada.
authors.forename: B A
authors.initials: BA
authors.lastname: Mallard
authors.affiliation: Department of Food Science, Ontario Agricultural College, University of Guelph, 43 McGilvray Street, Guelph, Ontario, N1G 2W1 Canada.
authors.forename: M W
authors.initials: MW
authors.lastname: Griffiths
authors.affiliation: Department of Food Science, Ontario Agricultural College, University of Guelph, 43 McGilvray Street, Guelph, Ontario, N1G 2W1 Canada.
authors.forename: M
authors.initials: M
authors.lastname: Corredig
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, 419 Gordon Street, Guelph, Ontario, N1G 2W1 Canada.
authors.forename: S
authors.initials: S
authors.lastname: Sharif
mesh_terms: D000818:Animals; D018122:B7-1 Antigen / Q000096:biosynthesis; D019013:CD40 Antigens / Q000096:biosynthesis; D002460:Cell Line; D003713:Dendritic Cells / Q000276:immunology*; D056747:Immunomodulation; D007249:Inflammation / Q000188:drug therapy* / Q000276:immunology; D016753:Interleukin-10 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D007779:Lactobacillus acidophilus / Q000145:classification / Q000276:immunology*; D052198:Lactobacillus helveticus / Q000145:classification / Q000276:immunology*; D008070:Lipopolysaccharides; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D019936:Probiotics / Q000494:pharmacology*; D051195:Toll-Like Receptor 2 / Q000096:biosynthesis; D051197:Toll-Like Receptor 4 / Q000096:biosynthesis; D051217:Toll-Like Receptor 9 / Q000096:biosynthesis; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D018122:B7-1 Antigen; D019013:CD40 Antigens; D015850:Interleukin-6; D008070:Lipopolysaccharides; C493486:Tlr2 protein, mouse; C493487:Tlr4 protein, mouse; C495370:Tlr9 protein, mouse; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051217:Toll-Like Receptor 9; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10
keywords: Lactobacillus; dendritic cells; immune modulation; immune system; lactic acid bacteria