Department of Medical Microbiology and Parasitology, Institutes of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
World J Gastroenterol. 2010 May 14;16(18):2283-90. doi: 10.3748/wjg.v16.i18.2283.
To elucidate the adherence and immunomodulatory properties of a probiotic strain Bifidobacterium lactis (B. lactis) HN019.
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-1beta (IL-1beta), interleukin-8, and tumor necrosis factor-alpha (TNF-alpha) gene expression were assessed while enzyme linked immunosorbent assay was used to detect IL-8 protein secretion.
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. typhimurium-induced pro-inflammatory responses. IL-8 secretion was reduced while IL-1beta and TNF-alpha mRNA expression level remained unchanged at baseline after treated with B. lactis HN019.
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.
阐明益生菌双歧杆菌（B. lactis）HN019 的黏附和免疫调节特性。
通过实时聚合酶链反应检测种特异性基因的拷贝数，对 B. lactis HN019 和鼠伤寒沙门氏菌（S. typhimurium）ATCC 14028 与 INT-407 细胞的黏附进行检测。通过透射电子显微镜进一步进行形态学研究。采用酶联免疫吸附试验检测白细胞介素-1β（IL-1β）、白细胞介素-8（IL-8）和肿瘤坏死因子-α（TNF-α）基因的表达。
S. typhimurium ATCC 14028 与 INT407 肠道上皮细胞的黏附被 B. lactis HN019 显著抑制。B. lactis HN019 可以被内化到 INT-407 细胞中，并在基线和鼠伤寒沙门氏菌诱导的促炎反应中减弱 IL-8 mRNA 水平。B. lactis HN019 处理后，IL-8 分泌减少，而 IL-1β和 TNF-αmRNA 表达水平在基线时保持不变。
B. lactis HN019 不会上调肠道上皮细胞表达的促炎细胞因子，它具有保护肠细胞免受肠道病原体引起的急性炎症反应的潜力。
