Abstract:

Objective  To explore the effect of the presence of EDTA in trypsin solution on detecting the apoptosis rate by flow cytometry method (FCM). Methods  Seven indigestible cell lines were divided into the control group and experimental group (treated by H₂O₂ to promote apoptosis). Cells were treated by different methods (digested by 0.25% trypsin without EDTA, 0.25% trypsin with EDTA, and 0.25% trypsin with EDTA and washed by 1×PBS after being centrifugated and supernatant was removed). Cells were labeled by Annexin V-FITC fluorescent antibodies and the apoptosis rate was detected by flow cytometry (FCM). The difference of apoptosis rate under the same digestion condition between two groups was calculated. Results  Results of statistical analysis showed that differences of the apoptosis rate of seven cell lines under three digestion conditions were not statistically significant (P>0.05). Conclusion  The presence of EDTA in trypsin solution has no significant effect on detecting the cell apoptosis by FCM. Given the anti-agglutinating characteristic of EDTA, it can be added into the trypsin solution for preparation of apoptosis samples for some indigestible cell lines.

Key words: flow cytometry method, EDTA, apoptosis, Annexin V, trypsin