IDENTIFICATION OF RAT PANCREATIC DUCT CELLS BY THEIR EXPRESSION OF CYTOKERATIN-7, CYTOKERATIN-19, AND CYTOKERATIN-20 IN-VIVO AND AFTER ISOLATION AND CULTURE

Cells from the excretory ducts of the pancreas are thought to be capab le of differentiating into exocrine and endocrine cells, To study this in rat models, markers must be found to identify the cells under diff erent experimental conditions, We tested antibodies to different cytok eratins (CKs) by immunocytochemical staining on pancreatic tissue sect ions from normal rats, after partial pancreatectomy, and after isolati on and culture of duct fragments, Monoclonal antibodies to human CK7, CK19, and CK20 were found to react specifically on rat pancreas tissue , as shown by Western blotting, CK20 and CK19 were immunocytochemicall y detected only in cells of the ductal system, from centroacinar cells to main ducts, CK7 was expressed by islets of Langerhans and by duct cells from main, inter-, and intralobular ducts, but not by centroacin ar and terminal duct tells, CKs7, 19, and 20 were also expressed in pr oliferating duct cells during tissue regeneration and after isolation and different periods of culture, We conclude that CKs 7, 19, and 20 a re very useful markers to study the differentiation of rat duct cells under experimental conditions in vivo and in vitro.