Abstract

The origin of insulin‐expressing β‐cells in the adult mammalian pancreas is controversial. During normal tissue turnover and following injury, β‐cells may be replaced by duplication of existing β‐cells.1 However, an alternative source of β‐cells has recently been proposed based on neogenesis from a Ngn3‐positive population present in regenerating pancreatic ducts.2 The appearance of β‐cells from Ngn3‐positive progenitors is reminiscent of normal pancreas development, and Ngn3‐expressing cells isolated from regenerating pancreas can generate the full repertoire of endocrine phenotypes. The isolation and characterisation of the equivalent human progenitors may represent a significant step forward in the hunt for a cure for diabetes. BioEssays 30:617–620, 2008. © 2008 Wiley Periodicals, Inc.