Fig. 9

Detection of CD133 on melanoma cell-derived extracellular lipidosomes. A-E Native (A-C) or CD9-GFP-transfected (D, E) FEMX-I cells growing on poly-L-lysine coverslips were processed for CLSM. PFA-fixed cells without (A-D) or with (E) saponin-permeabilization were immunolabeled with an anti-CD133 antibody (clone AC133 or W6B3C1) and co-stained with BODIPY™ 493/503 (A-C). Alternatively, they were either stained with fluorescence-conjugated WGA (D), which labels glycoconjugates at the cell membrane, or immunolabeled for Alix (E) and co-observed with CD9-GFP. Cells were counterstained with DAPI to highlight nuclei. Single x–y optical sections from top to bottom (four panels on the left) and composite (right panel) images of all sections are shown. A small CD133⁺ EV containing few lipid droplets is enlarged in panel C. Red and green arrowheads indicate CD133 and lipid droplets, respectively, while white arrow points CD9-GFP inside the large EVs. Scale bars are indicated