Fig. 1.

Small extracellular vesicles (sEVs) obtained from mesenchymal stromal cells (MSCs) cultured under hypoxic conditions increase cerebral microvascular endothelial cell proliferation. Relative number of human microvascular endothelial cells (hCMEC/D3) after exposure to different concentrations of A sEVs obtained from MSC culture media that contain platelet lysates (sEV_platelet), B sEVs obtained from MSCs (

source 41.5) cultured under regular ‘normoxic’ conditions (21% O₂; sEV_normoxic) or C sEVs obtained from MSCs (source 41.5) cultured under hypoxic conditions (1% O₂; sEV_hypoxic). In D, representative microphotographs for hCMEC/D3 cells exposed to control conditions or sEVs at a concentration of 50 µg/mL are shown. Data are mean ± SD values (n = 9 independent experiments). *p < 0.05, **p < 0.01, ***p < 0.001 compared with control. Scale bar: 400 µm in D