T1895 Fibroblast Populations in the Regenerated Rat Pancreas

were extirpated.Immunofluorescent staining was performed for alpha-SMA, amylase, cytokeratin-19, and von Willebrand Factor.Fluorescence in situ hybridization for Y chromosome was performed to detect the cells originating from bone marrow cells of male C57BL/6J mice.Results: We confirmed that hematologic reconstitution was almost complete after bone marrow transplantation.Repetitive injection of caerulein induced pancreatic fibrosis in mice.Co-localization of Y chromosome and alpha-SMA was detected in some cells in the pancreatic stroma of caerulein-induced mice, suggesting the origin of bone marrow.Proportion of bone marrow derived cells in alpha-SMA positive cells was approximately 18% in caerulein group.Meanwhile, few donor bone marrow-derived cells were detected in the pancreatic tissue of control mice.None of the bone marrow-derived cells were positive for amylase, cytokeratin-19, or von Willebrand factor.Conclusion: Our results suggest that bone marrow-derived cells contributed to the stellate cell population in the pancreas in mice.Further studies are necessary to clarify the role of bone marrow-derived cells in the development of pancreatic fibrosis.