HF serum provokes apoptosis in CB-MSC. A-C: Plasma membrane alterations (translocation of phosphatidyl serine) were assessed by flow cytometric analysis of cells subjected to a combined staining with AnnexinV (AV) and Propidium Iodide (PI). Boxplots show the percentages of dead (PI+) (A), apoptotic (AV+, PI-) (B) and viable cells (AV-, PI-) (C). There were significantly more apoptotic cells in the HF group. D-F: Western blots were performed to determine intracellular amounts of pro-apoptotic proteins, such as phospho-p53 (D), Bax (E) and active Caspase 3 (F). Boxplots illustrate quantified and adjusted band densities normalized to FCS for the human serum groups. Compared to the human control serum group, the HF group exhibited markedly higher levels of Caspase 3, whereas Bax expression did not differ. The boxplots indicate interquartile range (box), median (line), range (whiskers) and outliers (+/−).