Fig 1: CSPG4 and B7-H3 expression in canine-OMM-cell-derived SEVs. EX purification columns (Exo-spin Midi-Columns, Cell Guidance System, Cambridge, UK) were used to purify enriched EX-SEVs from the supernatant of fetal bovine serum-deprived CMM-12 cells. Briefly, the collected media was centrifuged to remove any cell debris and then incubated with the Exo-Spin Buffer to precipitate SEVs including EX and purified using Exo-Spin midi-column. Eluted SEVs were then ultracentrifuged at 100,000 x g and the pellet was resuspended in RIPA buffer for protein extraction. Representative immunoblot of CSPG4 and B7-H3 of lysates of SEVs is shown. Western Blot analysis for CSPG4 was performed as described in (73), mAb 376.96 was used for B7-H3 detection. CD9 (10626D; Thermo-Fisher Scientific) was used as the SEVs marker and ß-Actin (AC-15; Santa Cruz Biotechnology) was used as the protein-loading control.