Adhesion of Lactobacillus casei LC2W to different gastric cell lines

The adhensive ability of Lactobacillus casei LC2W to two gastric cell lines,i.e.MKN-45 and HGC-27,was tested under several variables(bacterial cell concentration,resuspending medium,the pH value of the resuspending solution) via morphological observation and cell counting under microscope.The results showed Lactobacillus casei LC2W was adhensive to both MKN-45 and HGC-27,especially the former.The adhension of Lactobacillus casei LC2W to the gastric cells was concentration-dependent to the lactobacillus cell resuspension,with the average numbers of bacterial cell adhered to per gastric cell increasing tilled the surface of the gastric cells saturated by the lactobacilli cells,when the lactobacilli cell resuspension reached 109cfu per milliliter.While the resuspending solution as well as the pH value of the solution demonstrated significantly effect on the bacterial's adhensive ability,the spent culture supernatant(SCS) of Lactobacillus casei LC2W and pH value 4 were optimal for the lactobacilli cells to adhere to the gastric cells among the resuspending solutions and the serial pH values tested.The adhensive ability of Lactobacillus casei LC2W to MKN-45 was insignificantly affected when the pH value of the SCS was neutralized to pH =7.0,which suggesting some substances in the SCS could promote the lactobacilli cells to the gastric cells.It was proposed that the adhension of Lactobacillus casei LC2W to the gastric cells was mediated by adhensin,which binding to the specific receptors on the mammal cells.