Western blotting of protein extracts for characteristic extracellular vesicles (i.e., CD63, Alix, Annexin I, Tsg101, Flotilin, Calnexin, HSP90) showed that only the endosomal marker CD63 and Alix, as well as the plasma membrane protein Annexin I, were expressed in vesicles isolated from MS patients; moreover, in both small and large fractions HSP90 was detected (Figure 4B). Here, CD63 is linked to myeloid sarcoma.