title: Effect of cell-surface components and metabolites of lactic acid bacteria and probiotic organisms on cytokine production and induction of CD25 expression in human peripheral mononuclear cells.
abstract: In the current study, the relative contribution of cell-surface components (CSC) and cell-free supernatants (CFS) in the immuno-modulatory properties of 17 strains of probiotic and lactic acid bacteria (LAB) was assessed. The production of pro- and antiinflammatory cytokines including IL-2, IL-4, IL-10, IL-12 p70, IFN-γ, tumor necrosis factor-α (TNF-α), and transforming growth factor-β was measured at different time points after stimulation of buffy coat derived-peripheral blood mononuclear cells (PBMC) from healthy donors with CSC and CFS of probiotic and LAB. Results showed that CSC of probiotic and LAB strains induced production of T helper 1 and 2 type cytokines. Transforming growth factor-β was stimulated at highest concentrations, followed by IL-10 and TNF-α. The CFS of all tested bacterial strains induced PBMC for significantly high levels of IL-10 secretion compared with unstimulated cells, but the values were less than lipopolysaccharide-stimulated cells. Cytokines due to CFS stimulation showed declined concentration for IL-2, TNF-α, and IL-4, and complete disappearance of IL-12, IFN-γ, and transforming growth factor-β in the cultured medium at 96 h of incubation. Results of cytokine data demonstrate proinflammatory TNF-α immune responses are mainly directed through cell-surface structures of probiotic and LAB, but antiinflammatory immune responses are mediated both by metabolites and cell-surfaces of these bacteria. The induction of CD4(+)CD25(+) regulatory T cells after stimulation of PBMC with CSC and CFS of probiotic and LAB showed regulatory T cell activity appeared to be influenced both by the CSC and metabolites, but was principally triggered by cell surfaces of probiotic and LAB strains.
authors.affiliation: Advanced Food Systems Research Unit, College of Health and Biomedicine, Victoria University, Werribee Campus, PO Box 14428, Melbourne 8001, Australia.
authors.forename: R
authors.initials: R
authors.lastname: Ashraf
authors.affiliation: Advanced Food Systems Research Unit, College of Health and Biomedicine, Victoria University, Werribee Campus, PO Box 14428, Melbourne 8001, Australia.
authors.forename: T
authors.initials: T
authors.lastname: Vasiljevic
authors.affiliation: School of Exercise and Nutrition Sciences, Faculty of Health, Gut Health SRC Molecular and Medical Research, Deakin University, Burwood, Victoria 3125, Australia.
authors.forename: S C
authors.initials: SC
authors.lastname: Smith
authors.affiliation: Advanced Food Systems Research Unit, College of Health and Biomedicine, Victoria University, Werribee Campus, PO Box 14428, Melbourne 8001, Australia. Electronic address: Osaana.Donkor@vu.edu.au.
authors.forename: O N
authors.initials: ON
authors.lastname: Donkor
mesh_terms: D001644:Bifidobacterium / Q000378:metabolism*; D016207:Cytokines / Q000096:biosynthesis*; D006801:Humans; D007778:Lactobacillus / Q000378:metabolism*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D019936:Probiotics / Q000737:chemistry*; D048249:Streptococcus thermophilus / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism*
chemical_list: D016207:Cytokines
keywords: cell-free culture supernatant; cell-surface component; probiotic bacteria; regulatory T-cell