Open AccessExtracellular vesicles from human plasma and serum are carriers of extravesicular cargo—Implications for biomarker discovery
Author(s) -
Mari Palviainen,
Mayank Saraswat,
Zoltán Varga,
Diána Kitka,
Maarit Neuvonen,
Maija Puhka,
Sakari Joenväärä,
Risto Renkonen,
Rienk Nieuwland,
Maarit Takatalo,
Pia Siljander
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0236439
Subject(s) - chemistry , blood proteins , flow cytometry , extracellular vesicles , western blot , extracellular vesicle , chromatography , biomarker , microvesicles , biochemistry , microbiology and biotechnology , biology , gene , microrna
Extracellular vesicles (EVs) in human blood are a potential source of biomarkers. To which extent anticoagulation affects their concentration, cellular origin and protein composition is largely unexplored. To study this, blood from 23 healthy subjects was collected in acid citrate dextrose (ACD), citrate or EDTA, or without anticoagulation to obtain serum. EVs were isolated by ultracentrifugation or by size-exclusion chromatography (SEC) for fluorescence-SEC. EVs were analyzed by micro flow cytometry, NTA, TEM, Western blot, and protein mass spectrometry. The plasma EV concentration was unaffected by anticoagulants, but serum contained more platelet EVs. The protein composition of plasma EVs differed between anticoagulants, and between plasma and serum. Comparison to other studies further revealed that the shared EV protein composition resembles the “protein corona” of synthetic nanoparticles incubated in plasma or serum. In conclusion, we have validated a higher concentration of platelet EVs in serum than plasma by contemporary EV methods. Anticoagulation should be carefully described (i) to enable study comparison, (ii) to utilize available sample cohorts, and (iii) when preparing/selecting biobank samples. Further, the similarity of the EV protein corona and that of nanoparticles implicates that EVs carry both intravesicular and extravesicular cargo, which will expand their applicability for biomarker discovery.