Increased susceptibility to apoptosis in late passage HUVECs.

<p>A. Expression of <i>BAX</i> and <i>BCL2</i> mRNA in P4, P8 and P12 cells evaluated by qPCR; B. <i>BAX</i> and <i>BCL2</i> protein content evaluated by Western blots. Data from 3–5 independent experiments are expressed as fold change in relation to P4 values ± SEM. C. Apoptosis in HUVECs in response to 24-hr exposure to TNFα (50 µg/ml) measured using polycaspase staining. Upper panel- Representative images of apoptotic cells (green) in P4 and P12 cells treated with TNFα. Lower panel – Quantitation of apoptotic response as a percentage of total cell number. (*) – p<0.05 compared to P4; (†) – p<0.05 compared to the same passage control.