Influence of selected cytokines on MSC proliferation; receptor expression profiles and concentration. (A) MSC were seeded in 5% pHPL, tPRP and FBS, respectively, and stimulated with for 3 days with 50 ng/ml HGF, 10 ng/ml IGF-1 or 25 ng/ml bFGF. Cell counts were acquired with the CellTiter-Glo assay and then normalized to the unstimulated control to derive relative cell count values. (B)% positivity of IGF, FGF and HGF receptor expression of BM- and LA-MSC (donors 1–3, respectively) in pHPL, tPRP and FBS assessed by flow cytometry. (C – E): IGF, FGF and HGF concentrations were determined by ELISA in pHPL and tPRP supplemented medium (medium, 6 different batches); medium stored for 24 h (control medium) and conditioned by MSC (CM) (each n = 3). Symbols indicate statistically significant diffences between: * stimulation; + supplements; # MSC sources; (one symbol p < 0.05; two symbols p < 0.01).