Inhibiting Exosome Biogenesis for Purity

During the isolation of exosomes, co-elution of proteins may occur and constitute a source of contamination. This can lead to a misinterpretation of the association of these proteins with exosomal fractions [57 (link)]. To avoid this bias, it is usual to inhibit exosome biogenesis, in order to check the level of contamination during fractionation. We used GW4869 to inhibit exosome production. GW4869 is a strong inhibitor of neutral sphingomyelinases that, by preventing the formation of intraluminal vesicles, is able to block exosome production. Cells were treated overnight with 10 µM GW4869. In parallel, control cells were treated with the same volume of DMSO. CCS were collected and exosome fractions were prepared using the Exoeasy Maxi kit^®.