Characterization of CLL exosomes in plasma. (A) Exosomes were purified by differential centrifugation from CLL patient plasma and subjected to NTA measurement for concentration and size distribution. The representative plot of each CLL sample present here was generated from the average of 5 30-second videos. (B) Dot plot showing the range of exosome concentrations detected in CLL plasma (n = 54). (C) Isolated CLL plasma-derived exosomes were immunoblotted for exosome markers CD63 and CD9. Purified exosomes showed enriched CD63 and CD9 expression compared with plasma samples.