During embryogenesis, islet cells differentiate from primitive duct-like cells. This process
leads to the formation of islets in the mesenchyme adjacent to the ducts. In the postnatal
period, any further expansion of the pancreatic endocrine cell mass will manifest itself either
by a limited proliferation of the existing islet cells, or by a reiteration of ontogenetic
development. It is the latter, cell transformation by a process of differentiation from a
multipotential cell, that will be referred to in this review as islet neogenesis. To better …