Aim: Extracellular vesicles (EVs) are nano-sized membrane particles released from most cell types and play an essential role in intercellular communication. This study aims to characterise the EVs in cryoprecipitate, a clinical vital blood component derived from fresh frozen plasma (FFP) that is largely unknown in the EV field.
Method: Individual cryoprecipitate and FFP units were obtained from Australian Red Cross Lifeblood, and EVs were isolated using size-exclusion chromatography. The purified EVs were then characterised based on the minimal information for studies of extracellular vesicles (MISEV2018). Nanoparticle Tracking Analysis (NTA) was utilised to determine the size distribution and concentration. Western blotting was employed to validate the isolated vesicles for the common EV-enriched markers. In addition, we used transmission electron microscopy (TEM) to perform structural characterisation of the EVs.
Results: The results showed EVs with a size from approximately 30-200 nanometres in diameter, with a cup shaped morphology when observed using TEM. Also, western blot analysis confirmed the presence of common EV markers such as CD9, CD81 and flotillin-1 in cryoprecipitate vesicles, which differ from those found in FFP. Cryoprecipitate EVs are more enriched in CD9 compared to FFP, while the opposite for CD81.
Conclusion: To the best of our knowledge, this was the first study to isolate and characterise EVs in the blood component cryoprecipitate based on MISEV2018 guidelines.