Adhesion of some Bifidobacterial Strains to Human Enterocyte-like Cells and Binding to Mucosal Glycoproteins
Aissi, E. A.
- Publisher: Microbial Ecology in Health and Disease
Microbial Ecology in Health and Disease
Bifidobacteria have been considered to exert beneficial in uence on their hosts’ health, thereby, four species of Bifiobacterium (B. bifidum, B. longum, B. breve and B. animalis) are commonly introduced into fermented dairy products as probiotics. Before proliferation, bacteria must interact with intestinal structures. For a better understanding of the relationships between the bacteria and the intestinal tract, we tested four bifidobacterial strains for their abilities to adhere to human enterocyte-like HT-29, Caco-2, INT 407 and LS 174 T cells in culture and to variable extracellular matrix molecules. In this study we reported three complementary methods: microscopic examinations, an ELISA test and a  ow cytometric fluorimetry assay. Only Bifidobacterium bifidum DSM 20082 bound to mucins, to extracellular matrix molecules and to cells lines tested. This adhesion occurs to the apical brush border of cultured cells. Bacterial adhesion settled quickly and was dependent on many parameters such as the number and the age of bacteria used, pH and the incubation time duration, heat shock and pronase treatment of bacteria and the origin of the peptone used to prepare bacterial culture medium. Mucus from different origins and various extracellular matrix molecules inhibited the bacterial adhesion to cultured cells. These results suggested that this bacterial strain adheres by a surface associated proteinaceous components and showed the importance of the environmental conditions for bacterial adhesive activities.Keywords : Bifidobacteria, adhesion, human enterocyte-like cells, mucosal glycoproteins, extracellular matrix molecules.