Detection of Cell Apoptosis With Flow Cytometry

The eBioscience Annexin V-FITC Apoptosis Detection Kit (BMS500FI-300, Thermo Fisher Scientific, USA) was used to detect cell apoptosis according to the manufacturer's instruction. Briefly, the cells were collected and washed once with PBS (pH 7.2), then were resuspended with 500 μl stain buffer (FBS) and centrifuged at room temperature and 1,000 rpm for 5 min. The supernatant was discarded. The cells were washed once with PBS (pH 7.2), resuspended with 200 μl binding buffer and 5 μl of Annexin V labeled with Fluorescein Isothiocyanate (FITC) was added, gently mixed and incubated in dark (room temperature) for 15 min, then 10 μl of PI solution was added followed by detecting the percentage of living cells, dead cells and apoptotic cells on a flow cytometer.