CELL-ADHESION AND MIGRATION .1. NEUTROPHIL ADHESIVE INTERACTIONS WITHINTESTINAL EPITHELIUM

In many inflammatory conditions of the gastrointestinal tract, disease activity and patient symptoms correlate with the histological finding of neutrophil (PMN) migration across the epithelium. PMN interactions with intestinal epithelium can influence epithelial functions ranging from barrier maintenance to electrolyte secretion. Additionally, PMN recruitment to the epithelium can be modulated by epithelial interacti ons with luminal enteric pathogens. Adhesive interactions between PMN and intestinal epithelial cells have been shown to be distinct from in teractions of PMN with endothelia. In particular, PMN transepithelial migration is modulated by a distinct array of cytokines including inte rferon-gamma and interleukin-4 and requires the PMN beta(2)-integrin C D11b/CD18 but is independent of CD11a/CD18, selectins, and intercellul ar adhesion molecule 1. Additionally, an integral membrane protein ter med CD47 has recently been shown to play an important role in PMN tran sepithelial migration at point(s) subsequent to initial adhesive inter actions. This article provides a brief overview of PMN interactions wi th epithelia and their functional consequences in relation to inflamma tory disease.