Dead cell apoptosis detection kit

The apoptotic status of AEC II cells was detected using the Dead Cell Apoptosis Detection kit (Catalog No. V13241, Invitrogen/Life Technologies, Carlsbad, CA, USA) following the instructions of the manufacturer. In this study, apoptosis was examined using the Annexin V/7-AAD double-staining method. AEC II cells were harvested using 0.25% trypsin and rinsed 2 times with PBS, then suspended in 500 μl of binding buffer. The suspended AEC II cells were treated with Annexin V-FITC (5 μl) at 4°C for 10 min. Then, the AEC II cells were treated with 7-ADD solution (10 μl) at 4°C for 5 min. Finally, AEC II cell apoptosis was analyzed using an FACS flow cytometer (BD Biosciences Inc. Brea, IN, USA). Early apoptosis was regarded as the cell percentage in the P3-Q3 quadrant, and late apoptosis was regarded as the cell percentage in the P3-Q2 quadrant.

Flow cytometry was used to detect the percentage of apoptotic cells by a Dead Cell Apoptosis Detection Kit with Annexin V and PI (Invitrogen). Briefly, at 48 h after transfection of plasmid, cells were harvested and suspended in Annexin Binding buffer. After that, PI and Annexin V were added into the above cell suspension and incubated at room temperature for 30 min. Afterwards, cells were subjected to flow cytometry for analysis of apoptosis. The cells positive for Annexin V was at early apoptosis and cells positive for both Annexin V and PI were at later apoptosis.