Active antithrombin glycoforms are selectively physiosorbed on plasma extracellular vesicles

Antithrombin (AT) is a glycoprotein produced by the liver and a principal antagonistof active clotting proteases. A deficit in AT function leads to AT qualitative deficiency,challenging to diagnose. Here we report that active AT may travel physiosorbed on thesurface of plasma extracellular vesicles (EVs), contributing to form the “EV-proteincorona.” The corona is enriched in specific AT glycoforms, thus suggesting glycosyla-tion to play a key role in AT partitioning between EVs and plasma. Differences in ATglycoform composition of the corona of EVs separated from plasma of healthy andAT qualitative deficiency-affected subjects were also noticed. This suggests deconstructing the plasma into its nanostructured components, as EVs, could suggest noveldirections to unravel pathophysiological mechanisms.