Fig. 4

MPs obtained from endoglin-overexpressing HPAECs stimulate endothelial cell survival and angiogenesis in vitro. a Internalisation of fluorescently-labelled MPs by HPAECs (2 h incubation). In the merged image, PKH26 is red, HA is blue and endoglin is green, as indicated. White pixels mark co-localization of PKH26, HA and endoglin and indicate intracellular localization of microparticles carrying recombinant endoglin (Image J analysis). Bar = 2 μm. b Cell proliferation, (c) cell viability and (d) angiogenesis/tube formation in HPAECs treated with MPs isolated from untreated (control) HPAECs, cells transfected with empty pDisplay vector and HPAECs overexpressing pDisplay-L- endoglin, as indicated. e Representative images of tube formation in cells transfected with pDisplay or pDisplay-L-endoglin.*P < 0.05; ***P < 0.001, comparison with transfection controls; Bar = 50 μm; n = 3