Fig 5.

mRNA delivery reduces cell viability without triggering apoptosis. (A) Cell viability was determined using the MTT assay at the indicated times for 3 days after mRNA delivery of mRNA constructs to KB cells. Mock (PBS)-transfected cells were used as a control, with their viability set at 100%. Each experiment was done in triplicate and repeated at least twice. Statistical analysis was performed using Student's t test. *, significantly decreased compared to untransfected cells (P < 0.05). (B) Analysis of apoptotic cells by flow cytometry after delivery of mRNA constructs. Cells that were positively stained by annexin V-FITC by flow cytometry were considered apoptotic. In panels A and B, error bars show the means ± SD for three to six independent experiments. (C) Western blot analysis of PARP cleavage after delivery of mRNA constructs. Mock (PBS)-transfected (vehicle) cells and untransfected cells were used as controls.