Review article: Effector role of epithelia in inflammation — interaction with bacteria

Abstract

The common response to infection is infiltration of the affected tissue by inflammatory cells. It is now recognized that the epithelium plays a crucial role in this immunological process by producing an array of proinflammatory cytokines including interleukin‐8, tumour necrosis factor‐α, monocyte chemotactic protein‐1, granulocytemacrophage colony‐stimulating factor, extractable nuclear antigen‐78 and others. The response of the intestinal epithelium to bacterial pathogens is particularly intriguing because it is literally bathed by normal bacterial flora and bacterial components/products yet remains immunologically quiescent despite this potentially hostile environment. In contrast, when challenged by bacterial pathogens, intestinal epithelial cells exhibit a vigorous immunological response. Our laboratory has, therefore, focused on the immune response of intestinal epithelial cells when confronted by a specific bacterial pathogen, enteropathogenic Escherichia coli.