Fig. 4

Validation of the UC-SEC method to isolate microglial EVs. a Nanoparticle Tracking Analysis (NTA) of SEC fractions. The number of particles/mL for each fraction is presented with a black dot in each replicate. The median value is represented by a green bar. The Fractions F1–F4, F5–F7 and F8–F20 were respectively pooled in P1-EV‒, P2-EV+  and P3-EV‒ samples. b Transmission electron microscopy of P2-EV+. The observation revealed the presence of EVs in a size range around 200 nm. EVs aggregates were also observed (white arrow). c Comparison of identified proteins between P1-EV‒ and P2-EV+. The Venn diagram presents protein signatures showing 51 common proteins and 12 or 76 proteins exclusively found in P1-EV‒ or P2-EV+. d Comparison of identified proteins between P2-EV+ and P3-EV‒. The Venn diagram presents protein signatures showing 41 common proteins and 84 or 2 proteins exclusively found in P2-EV+ or P3-EV‒. c, d A complementary analysis using Perseus software allowed the relative quantification of the common proteins. The heatmaps only represent clusters of differentially represented proteins. The over-represented proteins of P2-EV+ are framed in yellow. e Molecule symbols of the 29 P2-EV+ proteins detected in the top 100 ExoCarta database as EV markers. Among these EV markers, are represented in gray the proteins exclusive to P2-EV+. f, g Gene Ontology (GO) analysis of biological pathways and cellular components for proteins exclusive to P2-EV+ and proteins over-represented in P2-EV+ compared to P3-EV‒. The values are represented in percentage of total proteins