Caveolin-1 in monolayer HSC-3 extracts (A) and in exosomes isolated from their media (B-D). A. Caveolin-1 protein are seen as strong monomeric bands (~21 kDa) (and in complex forms, ~50 kDa – 60 kDa) in whole HSC-3 cell extracts cultured in monolayers under normoxic (NOR) conditions. Hypoxic (HYP) oxidative conditions and hypoxia mimicking CoCl2 media yield similar results. B. Exosomes isolated from the media of HSC-3 normoxic monolayer submitted to Western blotting for caveolin-1 show strong bands in the 20–23 kDa form (and in complex forms, ~50 kDa – 60 kDa). C. Results of ELISA tests performed on the exosomes isolated from HSC-3 monolayer media reveal caveolin-1 expression. The results are presented as the mean amount (±SD) of each protein of experiments with and without APMA induction. D. ELISA performed on HSC-3 exosomes shows the expression of the exosomal markers, CD63, CD9 and CD81. The results are presented as the mean amount (±SD) of each protein, with and without APMA induction. E. Immuno-electron microscopy that was performed on the monolayer media-isolated exosomes features round-shaped, membrane-bound nanoparticles that contain dots positive for both caveolin-1 and CD63.