AIM: To evaluate the in vitro immunomodulation capacity of various non-pathogenic yeast strains and to investigate the ability of some of these food grade yeasts to prevent experimental colitis in mice.METHODS: In vit...AIM: To evaluate the in vitro immunomodulation capacity of various non-pathogenic yeast strains and to investigate the ability of some of these food grade yeasts to prevent experimental colitis in mice.METHODS: In vitro immunomodulation was assessed by measuring cytokines [interleukin (IL)-12p70,IL-10,tumor necrosis factor and interferon γ] released by human peripheral blood mononuclear cells after 24 h stimulation with 6 live yeast strains (Saccharomyces ssp.) and with bacterial reference strains.A murine model of acute 2-4-6-trinitrobenzene sulfonic acid (TNBS)-colitis was next used to evaluate the distinct prophylactic protective capacities of three yeast strains compared with the performance of prednisolone treatment.RESULTS: The six yeast strains all showed similar non-discriminating anti-inflammatory potential when tested on immunocompetent cells in vitro .However,although they exhibited similar colonization patterns in vivo ,some yeast strains showed significant anti-inflammatory activities in the TNBS-induced colitis model,whereas others had weaker or no preventive effect at all,as evidenced by colitis markers (body-weight loss,macroscopic and histological scores,myeloperoxidase activities and blood inflammatory markers).CONCLUSION: A careful selection of strains is required among the biodiversity of yeasts for specific clinical studies,including applications in inflammatory bowel disease and other therapeutic uses.展开更多
AIM: To investigate the correlation between in vitro and in vivo immunomodulation potential of the probiotic strain and its ability to prevent experimental colitis in mice. METHODS: In vitro immunomodulation was ass...AIM: To investigate the correlation between in vitro and in vivo immunomodulation potential of the probiotic strain and its ability to prevent experimental colitis in mice. METHODS: In vitro immunomodulation was assessed by measuring interleukJn (IL)-12p70, IL-10, tumor necrosis factor alpha (TNFα) and interferon 7 (IFNγ) release by human peripheral blood mononuclear cells (PBMCs) after 24 h stimulation with 13 live bacterial strains. A murine model of acute TNBS-colitis was next used to evaluate the prophylactic protective capacity of the same set of strains. RESULTS: A strain-specific in vivo protection was observed. The strains displaying an in vitro potential to induce higher levels of the anti-inflammatory cytokine IL-10 and lower levels of the inflammatory cytokine IL-12, offered the best protection in the in vivo colitis model. In contrast, strains leading to a low IL-10/IU12 cytokine ratio could not significantly attenuate colitis symptoms, CONCLUSION:These results show that we could predict the in vivo protective capacity of the studied lactic acid bacteria (LAB) based on the cytokine profile we established in vitro. The PBHC-based assay we used may thus serve as a useful primary indicator to narrow down the number of candidate strains to be tested in murine models for their anti-inflammatory potential.展开更多
文摘AIM: To evaluate the in vitro immunomodulation capacity of various non-pathogenic yeast strains and to investigate the ability of some of these food grade yeasts to prevent experimental colitis in mice.METHODS: In vitro immunomodulation was assessed by measuring cytokines [interleukin (IL)-12p70,IL-10,tumor necrosis factor and interferon γ] released by human peripheral blood mononuclear cells after 24 h stimulation with 6 live yeast strains (Saccharomyces ssp.) and with bacterial reference strains.A murine model of acute 2-4-6-trinitrobenzene sulfonic acid (TNBS)-colitis was next used to evaluate the distinct prophylactic protective capacities of three yeast strains compared with the performance of prednisolone treatment.RESULTS: The six yeast strains all showed similar non-discriminating anti-inflammatory potential when tested on immunocompetent cells in vitro .However,although they exhibited similar colonization patterns in vivo ,some yeast strains showed significant anti-inflammatory activities in the TNBS-induced colitis model,whereas others had weaker or no preventive effect at all,as evidenced by colitis markers (body-weight loss,macroscopic and histological scores,myeloperoxidase activities and blood inflammatory markers).CONCLUSION: A careful selection of strains is required among the biodiversity of yeasts for specific clinical studies,including applications in inflammatory bowel disease and other therapeutic uses.
基金Supported by the EU granted QLK1-2000-00146 DEPROHEALTH research program, Institut Pasteur de Lille funding and funds from DANISCO France
文摘AIM: To investigate the correlation between in vitro and in vivo immunomodulation potential of the probiotic strain and its ability to prevent experimental colitis in mice. METHODS: In vitro immunomodulation was assessed by measuring interleukJn (IL)-12p70, IL-10, tumor necrosis factor alpha (TNFα) and interferon 7 (IFNγ) release by human peripheral blood mononuclear cells (PBMCs) after 24 h stimulation with 13 live bacterial strains. A murine model of acute TNBS-colitis was next used to evaluate the prophylactic protective capacity of the same set of strains. RESULTS: A strain-specific in vivo protection was observed. The strains displaying an in vitro potential to induce higher levels of the anti-inflammatory cytokine IL-10 and lower levels of the inflammatory cytokine IL-12, offered the best protection in the in vivo colitis model. In contrast, strains leading to a low IL-10/IU12 cytokine ratio could not significantly attenuate colitis symptoms, CONCLUSION:These results show that we could predict the in vivo protective capacity of the studied lactic acid bacteria (LAB) based on the cytokine profile we established in vitro. The PBHC-based assay we used may thus serve as a useful primary indicator to narrow down the number of candidate strains to be tested in murine models for their anti-inflammatory potential.