Expression of a neural stem/progenitor cell marker nestin in salivary glands

Salivary glands have the ability to regenerate yet the origin and markers of stem progenitor cells involved in this regeneration are still unclear We have previously reported that the expression of cytokeratin which is considered as a marker of both basal myoepithelial and progenitor cells in salivary glands was enhanced by tissue injury In this study to identify more specific markers for progenitor cells of salivary glands we examined the expression and localization of nestin in damaged tissues by duct ligation Changes in mouse parotid glands after unilateral obstruction of the main excretory duct were analyzed histologically with immunoblot analysis and with immunohistochemical staining Atrophy of acinar cells was observed on the side of duct ligation with hematoxylin and eosin staining On the other hand the contralateral side and sham operated salivary glands did not change morphologically The amount of nestin protein on the ligated side was increased and was significantly higher than on the contralateral side at day Immunohistochemical staining demonstrated nestin positive cells in the ducts and the atrophied acinar cells and around them And some cells expressed both nestin and cytokeratin Ki positive cells were also increased at day on the ligated side indicating that proliferation of progenitor cells begins simultaneously with the increase in nestin These results suggest that nestin may be a useful marker of progenitor cells in salivary glands