Fig. 6

ABCB5⁺ conditioned medium as well as co-culture rescue angiogenic properties of hypoxic HUVECs. A Representative images showing tube formation in HUVECs under different culture conditions (scale bar is 200 μm). B–D HUVECs were treated with 80 μM CoCl₂ or 120 μM DFO or 3 μM TG for 4 h. Then the HUVECs were harvested and seeded onto the growth factor reduced matrigel pre-coated 24-well plates (2.5 × 10⁴ cells/well). Afterward HUVECs were either co-cultured with ABCB5⁺ MSCs (CoCl₂-CO; DFO-CO; TG-CO) or cultured in ABCB5⁺ MSC conditioned medium (CoCl₂-CM; DFO-CM; TG-CM). Images were taken by an inverted microscope (Axiovert 200 M; Zeiss, Jena, Germany) after 6 h of incubation. The number of HUVECs meshes and junctions were analyzed by the angiogenesis analyzer plugin for NIH ImageJ version 1.52. Meshes and junctions after incubation with B CoCl₂, CoCl₂-CM and CoCl₂-CO treatments; C DFO, DFO-CM and DFO-CO treatments; D TG, TG-CM and TG-CO treatments. Data is represented as mean ± SD, n = 3 in each group, ns not significant, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001