Cryopreservation of UVC pathogen-inactivated platelets.

Area of Science:

• Transfusion Medicine
• Hematology
• Biotechnology

Background:

• Extending platelet shelf life and enhancing product safety are critical goals in transfusion medicine.
• Combining cryopreservation and pathogen inactivation (PI) offers a potential strategy, but research on their combined effects is limited.
• This study investigates the impact of PI treatment prior to cryopreservation on platelet quality and function.

Purpose of the Study:

• To evaluate the in vitro quality and function of cryopreserved platelets treated with UV-based pathogen inactivation (UVC-PI).
• To assess the feasibility of combining UVC-PI with cryopreservation for platelet products.
• To determine if UVC-PI treatment affects platelet susceptibility to cryopreservation-induced damage.

Main Methods:

• Matched pairs of buffy coat-derived platelets were either untreated (cryopreserved platelets, CPPs) or treated with UVC-PI (UVC-CPPs).
• Platelets were cryopreserved using dimethyl sulfoxide and thawed.
• In vitro quality and function were assessed immediately post-thaw and after 24 hours of room temperature storage using flow cytometry, aggregometry, thromboelastography, and thrombin generation assays.

Main Results:

• UVC-CPPs showed lower in vitro recovery and increased phosphatidylserine exposure and microparticle shedding compared to CPPs.
• Platelet surface marker expression (GPIX, GPIIb, GPIbα) was similar, but GPIIb/IIIa activation was higher in UVC-CPPs.
• Despite some markers of activation and damage, UVC-CPPs exhibited comparable functionality to CPPs in aggregometry, thromboelastography, and thrombin generation assays.

Conclusions:

• Cryopreservation of UVC-PI-treated platelet products is feasible.
• UVC-PI treatment may enhance platelet susceptibility to cryopreservation-related damage.
• This increased susceptibility is more evident during post-thaw storage at room temperature, highlighting the need for optimized storage conditions.