File:Mouse- pancreas differentiation model.jpg

Dynamic differentiation potential within the exocrine pancreas.

Multipotent pancreatic progenitors (E11.5-E13.5) express the digestive enzyme Cpa1, which is later restricted to acinar cells (E14.5-adult), together with Muc1 and Hnf1β [20].

While Cpa1+ cells cease contribution to islets from approximately E13.5 [7], Muc1+/Hnf1β+ cells continue to give rise to Neurog3+ endocrine precursors (pink nuclei) and islets (blue and green) through at least E15.5.

From around birth, Muc1+ and Hnf1β+ cells no longer contribute to the endocrine lineage, and mature islets are maintained by self-replication of those pre-existing. However, it remains a formal possibility that a subpopulation exists within the ductal network (dark blue cytoplasm), expressing neither Muc1 nor Hnf1β, from which β-cells continue to arise after birth.

Original File name: 1471-213X-10-38-11-l.jpg

Exocrine-to-endocrine differentiation is detectable only prior to birth in the uninjured mouse pancreas. Kopinke D, Murtaugh LC. BMC Dev Biol. 2010 Apr 8;10:38. PMID: 20377894 | PMC2858732 | BMC

"These results argue against a significant contribution by exocrine transdifferentiation to the normal postnatal expansion and maintenance of β-cell mass. Exocrine transdifferentiation has been proposed to occur during injury and regeneration, and our experimental model is suited to test this hypothesis in vivo."

Kopinke and Murtaugh BMC Developmental Biology 2010 10:38 doi:10.1186/1471-213X-10-38

© 2010 Kopinke and Murtaugh; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.