Review article: healing after inflammatory injury--coordination of a regulatory peptide network.

Intestinal epithelial cells are capable of producing a variety of cytokines and other regulatory factors that can affect functional regulation of the epithelium itself, through autocrine and paracrine mechanisms, as well as functional integration with lamina propria populations. The bi-directional nature of this cytokine network is now apparent, with the demonstration that both rat and human intestinal epithelium-derived cell lines possess a much greater array of cytokine receptors than previously anticipated.