Extracellular vesicles of different cellular origin feature distinct biomolecular corona dynamics.

Initially observed on synthetic nanoparticles, the existence of biomolecular corona and its role in determining nanoparticle identity and function are now beginning to be acknowledged in biogenic nanoparticles, particularly in extracellular vesicles - membrane-enclosed nanoparticle shuttling proteins, nucleic acids, and metabolites which are released by cells for physiological and pathological communication - we developed a methodology based on fluorescence correlation spectroscopy to track biomolecular corona formation on extracellular vesicles derived from human red blood cells and amniotic membrane mesenchymal stromal cells when these vesicles are dispersed in human plasma. The methodology allows for tracking corona dynamics in situ under physiological conditions. Results evidence that the two extracellular vesicle populations feature distinct corona dynamics. These findings indicate that the dynamics of the biomolecular corona may ultimately be linked to the cellular origin of the extracellular vesicles, revealing an additional level of heterogeneity, and possibly of bionanoscale identity, that characterizes circulating extracellular vesicles.