Isolation of extracellular vesicles from byproducts of cheese making by tangential flow filtration

Extracellular vesicles (EV) in milk, particularly exosomes, have attracted considerable attention as bioactive food compounds and for their use in drug delivery. The utility of bovine milk exosomes (BME) as animal feed additive and in drug delivery would be enhanced by cost-effective large-scale protocols for the enrichment of BME from byproducts in dairy plants. Here, we tested the hypothesis that BME may be enriched from byproducts from cheese making by using tangential flow filtration (TFF) of yields BME with properties similar to those observed in BME purified by serial ultracentrifugation. Three fractions of EV were purified from the whey fraction of cottage cheese making by using TFF: EV that passed through a membrane with a 50 kDa cut-off (50P), and subfractions of 50P that were retained (100R) or passed through (100P) a membrane with a 100-kDa cut-off; BME controls were prepared by serial ultracentrifugation.