The effect of pulsed electromagnetic fields on the proliferation of immunomagnetically separated human pre-cartilaginous stem cells

Abstract

Objective To study the biological effects of pulsed electromagnetic fields (PEMFs) on the pro-liferation of immunomagnetically separated human precartilaginous stem cells (PSCs) in vitro. Methods The cells from an aborted fetus's metaphysis were digested using collagenase. The PSCs were isolated by magnetic cell sorting (MACS), then subcultured and amplified. Flow cytometry, immunohistochemistry, immunofluorescence and RT-PCR analysis were performed to identify the purified PSCs. The PSCs were stimulated by PEMFs at 50 Hz frequency and 1 mT intensity. Cell proliferation was measured at different time points using methyl thiazolyl tetrazolium ( MTT), and the cell growth curve was plotted. Flow cytometry was applied to measure the cell cycle and apoptosis. Results The PSCs were successfully cultured. There was fibroblast growth factor receptor-3 (FGFR-3) on their sur-face. Cell proliferation was promoted after 4 and 6 days of PEMF stimulation. The percentage of cells at the S phase was higher than in a control group. Early, late and total rates of apoptosis in the experimental group decreased signifi-cantly. Conclusion PEMFs can enhance the proliferation and inhibit the apoptosis of human PSCs, and it is possi-ble to cultivate the high density human PSCs in vitro. Key words: Precartilaginous stem cells; Fibroblast growth factor receptor-3 ; Cell culture ; Pulsed elec-tromagnetic fields