【摘要】 目的以干酪乳杆菌(Lactobacillus casei,L.casei)胞外多糖(exopolysaccharides,EPS)为研究对象,研究其在体外对Balb/c小鼠小肠上皮细胞(small intestinal epithelial cell,IECs)增殖及其分泌IL-8、IL-10和TGF-β的影响。方法利用嗜热菌蛋白酶消化联合差速贴壁以及免疫细胞化学鉴定的方法对Balb/c小鼠IECs进行分离和鉴定,获得实验用的IECs。用不同质量浓度的L.casei EPS与IECs共培养,分别观察0.5、1、2 h和4 h后IECs的增殖情况。当用不同质量浓度的L.casei EPS处理IECs 2 h后,采用双抗体夹心ELISA法检测细胞培养上清液中细胞因子IL-8、IL-10和TGF-β的质量浓度。结果嗜热菌蛋白酶消化联合差速贴壁的方法能够获得纯度高与活性好的IECs;L.casei EPS能够促进IECs的增殖,显著上调上清液中IL-8、IL-10和TGF-β的分泌水平(P<0.05),EPS质量浓度在0~150μg/ml范围内呈剂量依赖关系,并且在150μg/ml的质量浓度时达到最大值。结论 L.casei EPS能够促进IECs的增殖及IL-8、IL-10和TGF-β的分泌水平。更多还原

【Abstract】 This study aimed to explore the impact of exopolysaccharide(EPS) from Lactobacillus casei(L.casei) on cell proliferation and cytokines IL-8,IL-10 and TGF-β secretion in small intestinal epithelial cells(IECs) from Balb/c mice.Murine IECs were isolated and identified by thermolysin digestion combined with differential adherence and immunocytochemistry method,respectively.Different concentrations of L.casei EPS were added to IECs culture supernatant on day 6 and cultured for 0.5 h,1 h,2 h and 4 h,then the proliferation of IECs were determined by WST-1 method.Furthermore,the content of IL-8,IL-10 and TGF-β in the supernatant co-cultured for 2 h were determined by ELISA.We found EPS could promote the proliferation of IECs,and up-regulate the production of IL-8,IL-10 and TGF-β in the supernatant significantly(P<0.05),and the up-regulation demonstrated a clear dose-dependent relationship with EPS in the range of 0-150 μg/ml.We concluded that EPS could promote the proliferation of IECs,meanwhile,could increase the content of IL-8,IL-10 and TGF-β in vitro.更多还原