枯草芽孢杆菌拮抗病原菌黏附和入侵Caco-2细胞的研究

Effects of Bacillus subtilis against pathogenic bacteria adhesion and invasion on Caco-2 cells

为探讨枯草芽孢杆菌及其培养上清液对产肠毒素大肠杆菌和鼠伤寒沙门氏菌的抗黏附作用,本试验将产肠毒素大肠杆菌K88或鼠伤寒沙门氏菌SL1344与枯草芽孢杆菌及其培养上清液先后加到Caco-2细胞上,用活菌计数的方法观察产肠毒素大肠杆菌、鼠伤寒沙门氏菌及枯草芽孢杆菌黏附Caco-2细胞的情况。结果显示:在排斥、竞争和置换试验中,枯草芽孢杆菌菌体均能够明显抑制K88和SL1344的黏附及SL1344的内化,在竞争试验时K88的黏附减少了71.2%、SL1344的黏附及内化减少了92.9%,但枯草芽孢杆菌的培养上清液只有在竞争试验中才能明显抑制K88和SL1344的黏附及SL1344内化。提示:枯草芽孢杆菌通过与病原菌竞争黏附位点来抑制病原菌对Caco-2细胞的黏附和入侵。

To investigate the inhibitory effect of Bacillus subtilis and supernatant on the adherence of pathogens,the experiment was conducted using viable bacteria counting method to evaluate inhibition of enterotoxic Escherichia coli K88 and Salmonella typhimurium SL1344 adhesion and invasion to Caco-2 cells by incubation with Bacillus subtilis and supernatant. The results showed that a decrease in the number of adhering K88 and SL1344 was observed,using either preincubation,postincubation or coincubation of the pathogens with Bacillus subtilis. Especially in competition test,the number of adhering K88 and SL1344 decreased 71. 2% and 92. 9% ,in competition test,the supernatant can inhibit the adherence and invasion of pathogens. The experiment suggested that Bacillus subtilis interact with intestinal epithelial cell receptor to competitively inhibit the adhesion and invasion of pathogens.