PZ promotes the migration and capillary-like tube formation of endothelial cells in vitro.
A, Representative images of scratch-wound closures after 8 and 24 hours of incubation with SDF-1 or PZ, ctrl corresponds to untreated cells. 100-fold magnification. Exposure of endothelial cells to PZ (3 µg/ml) led to a significantly higher wound closure after 8 (B) and 24 hours (C) comparable to stimulation with SDF-1 (50 ng/ml). Data are given as box plots indicating the median with the 25th and 75th percentiles. ANOVA on ranks; $ p<0.05 vs. ctrl; n = 4–7 independent experiments. D, Representative images of tubular networks after 8 hours of incubation in matrigel angiogenesis assay in the presence of SDF-1 (50 ng/ml), PZ (3 µg/ml), PZ+PTX and PTX alone (100 ng/ml), ctrl are untreated cells. 100-fold magnification. E, HUVECs showed significantly enhanced formation of capillary-like tubular structures on Matrigel when incubated with SDF-1 and PZ compared with ctrl. Coincubation of endothelial cells with PZ and PTX abolished the PZ-mediated increase in tube formation, while incubation with PTX alone had no effect on tube formation. Data are given as box plots indicating the median with the 25th and 75th percentiles. ANOVA on ranks; $ p<0.05 vs. ctrl; ß p<0.05 vs. PZ; n = 6 independent experiments.