In vitro differentiation capacity of esophageal progenitor cells with capacity for homing and repopulation of the ionizing irradiation-damaged esophagus.

BACKGROUND Ionizing irradiation of the esophagus results in development of esophagitis. In a mouse model, esophageal progenitor cells, isolated by either the side population (SP) sorting technique or a serial preplate technique, have been demonstrated to repopulate the irradiated esophagus of recipient mice. MATERIALS AND METHODS Esophageal progenitor cells (SP or preplate) as well as bone marrow cells were characterized phenotypically and by their ability to form colonies in methylcellulose in vitro. RESULTS Esophageal SP cells were able to differentiate to endothelin or vimentin positive colonies in vitro while preplate cells formed colonies that were uni-lineage, bi-lineage, or tri-lineage for macrophage, endothelin, or vimentin positive colonies. In methylcellulose culture, there was no difference in the types of colonies formed by the two techniques. As a control, hematopoietic progenitor cells formed multi-lineage hematopoietic colonies. CONCLUSION The data establish the existence of a subpopulation of esophageal progenitor cells with in vitro differentiation capacity to multiple adherent cellular lineages.