FIG. 2.
MSC proliferative potential and survival characteristics. (A) Days (mean±SEM) for population doubling through P2-P4 as estimated by the cell yield at the end of each passage compared with cells initially plated. (B) Results of optical density (mean±SEM) corresponding to the number of live cells over a 13-day culture using the MTT assay in MSCs at P2. Comparison between patients (■) and controls (□) was performed using a 2-way analysis of variance (ANOVA), and the F and P values are depicted. Graphs C–E depict the survival characteristics of MSCs. MSCs from P2 were stained with 7-AAD and analyzed by flow cytometry for the study of apoptosis. Dot plot D shows the proportion of 7-AAD− (R2; live), 7-AADdim (R3; early apoptotic), and 7-AADbright (R4; late apoptotic) cells in the gate of R1 corresponding to P2 MSCs. (E) Cumulative data showing the mean (±SEM) proportion of early- and late-apoptotic MSCs in patient (■) and healthy control (□) cultures at P2. Comparisons were performed by means of the nonparametric Mann–Whitney test, and the P values are shown. D, days in culture; SEM, standard error of the mean; MTT: methyl triazolyl tetrazolium; 7-AAD, 7-aminoactinomycin-D; SS, side scatter; FS, forward scatter.