AIM:To elucidate the adherence and immunomodulatory properties of a probiotic strain Bifidobacterium lactis(B.lactis) HN019.METHODS:Adhesion assays of B.lactis HN019 and Salmonella typhimurium(S.typhimurium) ATCC 1402...AIM:To elucidate the adherence and immunomodulatory properties of a probiotic strain Bifidobacterium lactis(B.lactis) HN019.METHODS:Adhesion assays of B.lactis HN019 and Salmonella typhimurium(S.typhimurium) ATCC 14028 to INT-407 cells were carried out by detecting copies of species-specific genes with real-time polymerase chain reaction.Morphological study was further conducted by transmission electron microscopy.Interleukin-1β(IL-1β),interleukin-8,and tumor necrosis factor-α(TNF-α) gene expression were assessed while enzyme linked immunosorbent assay was used to detect IL-8 protein secretion.RESULTS:The attachment of S.typhimurium ATCC 14028 to INT407 intestinal epithelial cells was inhibited significantly by B.lactis HN019.B.lactis HN019 could be internalized into the INT-407 cells and attenuated IL-8 mRNA level at both baseline and S.typhimuriuminduced pro-inflammatory responses.IL-8 secretion was reduced while IL-1β and TNF-α mRNA expression level remained unchanged at baseline after treated with B.lactis HN019.CONCLUSION:B.lactis HN019 does not up-regulate the intestinal epithelium expressed pro-inflammatory cytokine,it showed the potential to protect enterocytes from an acute inflammatory response induced by enteropathogen.展开更多
基金Supported by (in part) The National Key Program for Infe ctious Diseases of China,No 2008ZX10004-002,No 2008ZX1 0004-009,and No 2009ZX10004-712Program of Shanghai Subject Chief Scientist,No 09XD1402700
文摘AIM:To elucidate the adherence and immunomodulatory properties of a probiotic strain Bifidobacterium lactis(B.lactis) HN019.METHODS:Adhesion assays of B.lactis HN019 and Salmonella typhimurium(S.typhimurium) ATCC 14028 to INT-407 cells were carried out by detecting copies of species-specific genes with real-time polymerase chain reaction.Morphological study was further conducted by transmission electron microscopy.Interleukin-1β(IL-1β),interleukin-8,and tumor necrosis factor-α(TNF-α) gene expression were assessed while enzyme linked immunosorbent assay was used to detect IL-8 protein secretion.RESULTS:The attachment of S.typhimurium ATCC 14028 to INT407 intestinal epithelial cells was inhibited significantly by B.lactis HN019.B.lactis HN019 could be internalized into the INT-407 cells and attenuated IL-8 mRNA level at both baseline and S.typhimuriuminduced pro-inflammatory responses.IL-8 secretion was reduced while IL-1β and TNF-α mRNA expression level remained unchanged at baseline after treated with B.lactis HN019.CONCLUSION:B.lactis HN019 does not up-regulate the intestinal epithelium expressed pro-inflammatory cytokine,it showed the potential to protect enterocytes from an acute inflammatory response induced by enteropathogen.