Paneth cells and the innate immune responseWehkamp, Jan; Stange, Eduard FCurrent Opinion in Gastroenterology: November 2006 - Volume 22 - Issue 6 - p 644–650 doi: 10.1097/01.mog.0000245541.95408.86 Immunology Abstract Author Information Purpose of review: To review recently published studies presenting novel and relevant information on Paneth cells and their function. Recent findings: Paneth cells are secretory epithelial cells which are predominantly found in the small-intestinal crypts of Lieberkühn. Their most abundant products are α-defensins, which are endogenous antibiotics with activity against Gram-negative and Gram-positive bacteria, fungi, viruses and protozoa. The differentiation from stem-cell progenitors to Paneth cells is regulated by Wnt signalling via a complex gene programme, terminally including defensins. A disturbance of Paneth-cell differentiation and function may predipose to intestinal infections and appears to be a critical factor in the pathogenesis of ileal Crohn's disease, an inflammatory disease of the intestinal tract. Summary: It is conceivable that these recent findings together with a better understanding of underlying mechanisms involved in the regulation and biology of Paneth cells will open up new therapeutic avenues for preventing infection as well as for causally treating inflammatory bowel diseases. Robert Bosch Hospital and Dr Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany Correspondence to Jan Wehkamp, MD, Dr Margarete Fischer-Bosch – Institut für klinische Pharmakologie, Auerbachstr. 112, 70376 Stuttgart, Germany Tel: +49 711 8101 3753; fax: +49 711 85 92 95; e-mail: firstname.lastname@example.org © 2006 Lippincott Williams & Wilkins, Inc.