OBJECTIVETo establish a method for isolating and culturing human amniotic epithelial cells (hAECs) in a serum-free medium and investigate their transdifferentiation ability into islet-like cells.

METHODSThe culture condition of hAECs was optimized using DMEM with different supplements. The genetic stability of the tenth-passage cells was assessed by chromosome analysis and G-banding method. The stem cell characteristics of the cells were identified by examination of the surface markers using immunofluorescence methods. The endocrine-related genes and hormones of the cells were tested after induced differentiation into islet-like cells.

RESULTSThe hAECs allow stable passaging in the presence of 10 ng epidermal growth factor (EGF) in the culture medium. After 10 passages, the cells maintained a normal karyotype and G-banding profile. The hAECs expressed many multi-potent stem cell markers, including SSEA4, TRA-1-60, and TRA-1-81. After induced differentiation, the endocrine-related genes were expressed in the islet-like cells, including PDX1, ngn3, insulin and glucagon. Insulin secretion increased in the differentiated islet-like cells in response to high glucose exposure.

CONCLUSIONWe established a method for isolating and expanding the hAECs in a serum-free medium. hAECs possess stem cell characteristics and can be induced to differentiate into islet-like cells in vitro.