Measure of angiogenesis by iPSCs-derived ECs. (a) Representative images of vascular network formation (in-vitro matrigel assay) showing that HGPS iPSC-derived ECs formed fewer network segments compared to control. Results are reported graphically in (b). (c–g). Reduced neovascularization, shown by in-vivo matrigel plug assay, was observed in HGPS iPSC-ECs compared to non-HGPS iPSC-ECs. Images of CD31-immunostained sections (D) and HE stained section (F) with results graphically reported in (e) and (g), respectively. Images are derived from experiments with HGPS 167–1Q and non-HGPS 168–1P cells. N = 3 experiments per donor cells, Student t-test, **p ≤ 0.01.