Enteropathogenic Escherichia coli (EPEC) attachment to epithelial cells: exploiting the host cell cytoskeleton from the outside

Enteropathogenic Escherichia coli (EPEC), a leading cause of human infantil e diarrhoea, is the prototype for a family of intestinal bacterial pathogen s that induce attaching and effacing (A/E) lesions on host cells. A/E lesio ns are characterized by localized effacement of the brush border of enteroc ytes, intimate bacterial attachment and pedestal formation beneath the adhe rent bacteria. As a result of some recent breakthrough discoveries, EPEC ha s now emerged as a fascinating paradigm for the study of host-pathogen inte ractions and cytoskeletal rearrangements that occur at the host cell membra ne. EPEC uses a type III secretion machinery to attach to epithelial cells, translocating its own receptor for intimate attachment, Tir, into the host cell, which then binds to intimin on the bacterial surface. Studies of EPE C-induced cytoskeletal rearrangements have begun to provide clues as to the mechanisms used by this pathogen to subvert the host cell cytoskeleton and signalling pathways. These findings have unravelled new ways by which path ogenic bacteria exploit host processes from the cell surface and have shed new light on how EPEC might cause diarrhoea.