Interactions of enteric pathogens and the intestinal mucosa

Abstract

To cause disease in a mammalian host, enteric bacterial pathogens must overcome a variety of non-specific defence mechanisms in the host which include gastric acidity, intestinal motility, the normal intestinal microflora, and the mucous layer that coats the intestinal epithelial cells. Some attributes of pathogens that may assist them in combating normal resistance in the host are motility, the elaboration of glycosidases, and chemotactic and attachment factors. As a result of these properties, pathogens interact with the intestinal epithelium. Three different patterns of infection have been observed at the cell surface: attachment to the brush border (Vibrio choleraeand enterotoxigenicEscherichia coli) ; disruption of the brush border and attachment to the cell membrane (enteropathogenicE: coli) ; and invasion of the cell (shigellae and salmonellae).