Fig. 2

PEDF-sEVs suppress VEGF-induced angiogenic effects and VEGF-downstream signalling in HRECs. A Starved HRECs were treated with PEDF under VEGF stimulation for 24 h. Cell proliferation was measured using a CCK assay (OD = 450 nm, n = 8). B Starved HRECs were treated with sEVs under VEGF stimulation for 24 h. Cell proliferation was measured using a CCK assay (OD = 450 nm, n = 7). C Starved HRECs were treated with PEDF (400 ng/mL), sEVs (10 µg/mL), a mixture of PEDF (400 ng/mL) and sEVs (10 µg/mL) without sonication, or PEDF-sEVs (10 µg/mL) under VEGF (10 ng/mL) stimulation for 24 h. Cell proliferation was measured using a CCK assay (OD = 450 nm, n = 8). D Representative images and E Quantification of the Transwell assay of HRECs treated as in C after 24 h (n = 5); scale bar = 100 μm. F  Representative images and G Quantification of the scratch migration assay in HRECs treated as in C after 12 h (n = 5), scale bar = 200 μm. H Representative images and I Quantification of the tube formation assay in HRECs treated as in C after 2–4 h (n = 6), scale bar = 200 μm. J Starved HRECs were pre-treated with PEDF, sEVs, or PEDF-sEVs for 24 h and then stimulated with 10 ng/mL VEGF for 20 min. Representative western blots for pAKT, AKT, pERK1/2, and ERK1/2 showing VEGF-downstream signalling. K Quantitative analysis for qERK/ERK and qAKT/AKT in HRECs (n = 6). The data are represented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001