Choice for host-specific high-adhesive <i>Lactobacillus</i> strains

Abstract

Adhesive ability was tested in seven Lactobacillus solated from the chicken digestive tract after cultivation with CaCo-2 cells (intestinal epithelial cells), MDCK (dog kidney) cells and CEF (chicken embryo fiber) cells. We noted the following important observations regarding the adhesive ability between different Lactobacillus strains and three cell types: the adhesive interaction between the SDnB 7 , SDnE 1 and SDnA 3 lactobacillus strains and CaCo-2cells was greater compared to controls, the adhesive effect between SDnB 1 and CEF cells was also greater than controls and Lactobacillus showed only minimal adherence to MDCK cells. Incubation time also affected Lactobacillus adherence to CaCo-2cells: adhesive ability was optimal at 37°C when incubated for 2 days and this was confirmed by a local increase in the concentration of Lactobacillus around CaCo-2 cells when incubated for 24 h as opposed to 3 h. Adherence ability in lactobacillus was also tested at various concentrations (10 8 , 10 7 , 10 6 , 10 5 and 10 4 ). The number of Lactobacillus that adhered around the cells was significantly increased in the treatment with 10 8 bacterial cells. Transmission electron microscopy revealed that the cellularity of the junction between CaCo-2cells and Lactobacillus was not compromised. Transmission electron microscopy also revealed that the thalli fabric structure remained intact.