Fig. 4
Effect of EVs isolated from MSCs cultured in normoxic (18.4% O2) and physioxic (3% O2) conditions on CMEC tube formation. A Total meshed area, total segment length and branching interval as measured by ImageJ for CMECs cultured on Geltrex and exposed to EBM-2 (negative control), or EBM-2 supplemented with EVs at 10× and 20× original medium concentrations from normoxic or physioxic MSC cultures. Total meshed area represents the total area fully enclosed by tubes. Total segment length represents the sum of the total length of tube segments analyzed. Branching interval represents the mean distance that separates two branches in the analyzed area. N = 3–7, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, bars represent mean and SD. B 10× phase contrast images of CMECs on Geltrex at 6 h in each of the conditions. Scale bar = 100 μm