tailieunhanh - In vitro model for the study of Listeria and Salmonella adherence to intestinal epithelial cells

A quantitative test to study Listeria and Salmonella adherence to epithelial cells was developed. The quantitative test is rapid and allows the simultaneous testing of many variables such as the adherence ability of different bacteria to their target cells as well as the capability of various molecules to inhibit bacterial adherence. | Turk J Biol 25 (2001) 25-35 © T†BÜTAK In vitro Model for the Study of Listeria and Salmonella Adherence to Intestinal Epithelial Cells Nevzat YURDUSEV INRA, Laboratoire de Pathologie Infectieuse et Immunologie, 37380 Nouzilly - FRANCE Received: Abstract : A quantitative test to study Listeria and Salmonella adherence to epithelial cells was developed. The quantitative test is rapid and allows the simultaneous testing of many variables such as the adherence ability of different bacteria to their target cells as well as the capability of various molecules to inhibit bacterial adherence. By using a strain-specific standard curve in each test, the test for the quantification of adherent bacteria became specifically sensitive. Non-viable biotinylated bacteria and immobilized cells or their extract were found relevant for the study of bacteria-epithelial cell interactions. Adherence ability of Listeria strains was found to be 10-fold that of the Salmonella strains used in this study. Bovine milk was able to inhibit at least 90% of the adherence ability of Listeria and Salmonella strains. Milk components may be useful for the identification of bacterial surface molecules involved in adherence, which is the first key step in the pathogenicity of invasive bacteria. Preliminary results indicate that the test may also be used to determine the competitive adherence ability of bacterial strains. Key Words : Bacterial adhesion, Listeria, Salmonella, Epithelial cell, In vitro adherence model, Quantitative test, Adherence inhibition Introduction Adherence of pathogenic bacteria to host cells or tissues is a key step in virulence (1, 2). The complexity of in vivo adherence studies have been partly overcome by developing in vitro models (3-10). Adherence models use different combinations of bacteria and host cells: viable bacteria with living or immobilized host cells, or killed bacteria with either host cells in culture or animals (3, 8, 9, 11-14). A number of .