Abstract:

BACKGROUND: Stem-like cells have been found in human endometrium but the specificity marker has not been found. This kind of cells is difficult to be separated.
OBJECTIVE: To investigate the usefulness of aldehyde dehydrogenase (ALDH) activity as a marker for endometrial stem cells.
METHODS: Human endometrial cells were isolated and dissociated mechanically and enzymatically from human endometrium. Stromal and epithelial cells were separated by two series of filters. The ALDHhigh cells and ALDHlow cells were selected by flow cytometry based on ALDH activity. Limiting dilution culture was performed to culture these cells. Cell morphology and growth characteristics were observed. Flow cytometry analysis was used to identify the expression of c-kit, CD90, CD73 and CD29 markers in cultured cells.
RESULTS AND CONCLUSION: The proportion of ALDHhigh cells was (1.88±0.17)% in stromal cells. After primary cultured for 15 days, the colony forming rate of the ALDHhigh cells reached 4.50%±0.82% which were significantly higher than ALDHlow cells (1.06±0.34)% (P < 0.05). Meanwhile, the large colony forming number of ALDHhigh cells was higher than that of ALDHlow cells (P < 0.05). The ALDHhigh cells and colony forming were not detected in epithelial cells. The expressions of c-kit, CD29, CD90 and CD73 cells were positive in endometrium colony forming cells. Results have proved that ALDH activity detection can select the endometrial stem cells.