Functional Rebuilding Of Irradiated Glands With Human Amniotic Epithelial Cells In Mice

Objective:On account of the potential of human amniotic epithelial cells (hAECs) differentiated into acinar cells in vitro. We researched the differentiation abilities after hAECs transplantation in irradiated glands of mice in order to find a new stem cell resource for the cell replacement therapy in salivary gland diseases.Methods:(1) In this study, hAECs was isolated from human amnion tissue using mechanically minced and enzymatically digested and cultured in vitro, the phenotype of the cells were identificated by flow cytometry (FCM) and immunocytochemistry staining.(2) Forty C57BL/6male mices’ submandibular glands were irreversible damaged by15Gy (Gry) local irradiation.(3)The second filial generation hAECs were transplanted into the radiation damaged submandibular glands of mices through orthotopic transplantation. Untransplantation group were injected into the equivalence L-DMEM which has no blood serum. They are tested at different times after transplantation by histopathology and immunofluoroscence.Results:(1) The isolated hAECs have the typical features of stem cells. These cells were high expression of CD29, CD33and CK19, no-expression of CD34, CD44, CD45and CD71.(2) The weight of mice reduced obviously after local irradiation, and the flow rate of saliva reduced compared with normal. The submandibular glands appeared vasocongestion at6days, few void emerged in glandular lobule at10days and generous serous alveoli disappeared at30days by histopathology after irradiation.(3) Immunofluoroscence showed that MAB-1281positive cells were observed in cryosections at1,2,4and6weeks after transplantation. Double immunofluoroscence showed that MAB-1281positive cells were high expression of amylase, CK7and CK14at4weeks. The number of serous alveoli in submandibular salivary gland increased at1week and which recovers as normal1month leater by histopathology.(4) The volume of saliva collected in the first15min from mice after hAECs transplantation1month was (125.68±18.64) μl, about the control mice48.5%, and it is high no-transplantation mice.Conclusion:Human amniotic epithelial cells may differentiate into acinar cells and duct epithelial cells, improve salivary gland function of mice with irradiation, suggesting that hAECs may a new potential source for injuries salivary gland restoration.