Comparative study on AnnexinV/PI and TUNEL in detecting hepatocyte apoptosis

Objective To compare the advantages and disadvantages of AnnexinⅤ/PI with flow cytometry and TUNEL in detecting hepatocyte apoptosis. Methods Cultured human hepatocyte line HL-7702 was divided into TGF-β1 group(treated with TGF-β1 20 ng/ml for 72 h)and normal control group(incubated with equal PBS).Hepatocyte apoptosis was detected by AnnexinⅤ/PI with flow cytometry and TUNEL. Results Compared with normal control group,the percentages of early and total apoptosis significantly increased in TGF-β1 group by AnnexinⅤ/PI[(10.55±4.71)%vs(5.98±2.97)%,P0.01;(19.94±3.68)%vs(13.27±4.62)%,P0.05].By TUNEL assay,nuclei stained buffy were detected as positive cells.Meanwhile the cells changed into smaller,rounder and nuclear condensation.But normal nuclei were not stained.The percentage of hepatocyte apoptosis in TGF-β1 group was much higher than in normal control group[(30.25±6.43)%vs(4.75±0.96)%,P0.01].Conclusion AnnexinⅤ/PI with flow cytometry is more specific,while TUNEL assay is more sensitive.It is more precise to combine AnnexinⅤ/PI with TUNEL.