Fig. 4.

Impact of long-term expansion of DPSCs and aBMMSCs using three different culture media (CCM, StemMacs and StemPro) on β-galactosidase activity. a, b Optical microscopy photographs of DPSCs and aBMMSCs, respectively (sale bars: 100 μm). c Percentage of SA-β-gal-positive cells (DPSCs and aBMMSCs) at early, middle and late passages of each expansion medium. Values are mean (± SD) of DPSCs (n = 6 donors, experiments repeated three times in duplicates) and aBMMSCs (n = 4 donors, experiments repeated three times in duplicates). Asterisks indicate statistically significant differences (*p < 0.05; **p < 0.01) between middle vs early and late vs early passages for each cell type and medium separately. Upper case letters (A) indicate statistically significant differences between DPSCs and aBMMSCs expanded with the same medium (either CCM, StemMacs or StemPro) at each passage separately (either early, middle or late), while lowercase letters (a) indicate statistically significant differences between StemMacs vs CCM and between StemPro vs CCM for each cell type (either DPSCs or aBMMSCs) and each passage (either early, middle or late) separately. Statistical analyses were performed by two-way ANOVA followed by Tukey’s post-hoc tests. aBMMSC alveolar bone marrow mesenchymal stem cell, CCM complete culture medium, DPSC dental pulp stem cell, P cell passage, SA-β-gal beta-galactosidase