Fig. 6: Functional characterization of hPSC-derived VELs.

a Cartoon depicting the protocol that is used to differentiate hPSC to VELs in 10 days. b Tube formation assay of day 7 hPSC-derived VELs, the primary VECs and HAEC. Left: representative images; right: quantification of capillary-like structures in terms of branches and tube length by ImageJ. Scale bar: 25 μm. c Fluorescence signals showing that hPSC-derived VELs could uptake Ac-LDL, similar to primary VECs. d Confocal images showing the alignment of hPSC-derived VELs, the primary VECs from 16-year old and HAEC after exposed to fluid flow for 48 hpf. Fluid flow direction is shown by the black arrow. White arrows show the direction of individual cells. Scale bar: 25 μm. e Quantification of cell shape and orientation for primary VECs, VELs, and HAEC, under static and flow conditions (d). Cell shape and orientation were quantified by ImageJ. At least 50 cells were evaluated per condition across three independent replicates. Graph shows mean as horizontal bar. f The qRT-PCR analysis of indicated genes for VECs and VELs under static and flow conditions. All experiments were repeated three times. The paired t test in Graphpad software was used for the statistical analysis. Significant levels are: *p < 0.05; **P < 0.01; ***P < 0.001. Shown are representative images in (b–e).