BACKGROUND Room temperature–stored (20‐24°C) platelets (PLTs) have a shelf life of 5 days, making it logistically challenging to supply remote medical centers with PLT products. Cryopreservation of PLTs in dimethyl sulfoxide (DMSO) and storage at –80°C enables an extended shelf life up to 2 years. Although cryopreserved PLTs have been widely characterized under resting conditions, their ability to undergo agonist‐induced activation is yet to be fully explored. STUDY DESIGN AND METHODS Buffy coat PLTs were cryopreserved at –80°C with 5% to 6% DMSO and sampled before freezing and after thawing. PLTs were analyzed under resting conditions and after agonist stimulation with adenosine diphosphate, collagen, or thrombin receptor–activating peptide‐6. The expression of activation markers, microparticle formation, and calcium mobilization were analyzed by flow cytometry. Soluble PLT proteins present in the PLT supernatant were examined by enzyme‐linked immunosorbent assay. Protein phosphorylation was investigated with Western blotting. RESULTS After cryopreservation, PLTs displayed increased surface activation markers and higher basal calcium levels. Cryopreserved PLTs demonstrated diminished aggregation responses. Additionally, cryopreserved PLTs showed a limited ability to become activated (as measured by CD62P and phosphatidylserine exposure and cytokine release) after agonist stimulation. A reduction in the abundance and phosphorylation of key signaling proteins (Akt, Src, Lyn, ERK, and p38) was seen in cryopreserved PLTs. CONCLUSIONS Cryopreservation of PLTs induces dramatic changes to the basal PLT phenotype and renders them largely nonresponsive to agonist stimulation, likely due to the alterations in signal transduction. Therefore, further efforts are required to understand how cryopreserved PLTs achieve their hemostatic effect once transfused.
Conventional storage of platelet concentrates limits their shelf life to between 5 and 7 days due to the risk of bacterial proliferation and the development of the platelet storage lesion. Cold storage and cryopreservation of platelets may facilitate extension of the shelf life to weeks and years, and may also provide the benefit of being more haemostatically effective than conventionally stored platelets. Further, treatment of platelet concentrates with pathogen inactivation systems reduces bacterial contamination and provides a safeguard against the risk of emerging and re-emerging pathogens. While each of these alternative storage techniques is gaining traction individually, little work has been done to examine the effect of combining treatments in an effort to further improve product safety and minimize wastage. This review aims to discuss the benefits of alternative storage techniques and how they may be combined to alleviate the problems associated with conventional platelet storage.
BACKGROUND Extending the platelet (PLT) shelf life and enhancing product safety may be achieved by combining cryopreservation and pathogen inactivation (PI). Although studied individually, limited investigations into combining these treatments has been performed. The aim of this study was to investigate the effect of PI treating PLTs before cryopreservation on in vitro PLT quality and function. STUDY DESIGN AND METHODS ABO‐matched buffy coat–derived PLTs in PLT additive solution (SSP+; Macopharma) were pooled and split to form matched pairs (n = 8). One unit remained untreated and the other was treated with the THERAFLEX UV‐Platelets System (UVC; Macopharma). For cryopreservation, 5% to 6% dimethyl sulfoxide was added to the PLTs, and they were frozen at −80°C. After being thawed, untreated cryopreserved PLTs (CPPs) and UVC‐treated CPPs (UVC‐CPPs) were resuspended in plasma. In vitro quality was assessed immediately after thawing and after 24 hours of room temperature storage. RESULTS UVC‐CPPs had lower in vitro recovery compared to CPPs. By flow cytometry, PLTs demonstrated a similar abundance of GPIX (CD42a), GPIIb (CD41a), and GPIbα (CD42b‐HIP1), while the activation of GPIIb/IIIa (PAC‐1) was increased in UVC‐CPPs compared to CPPs. UVC‐CPPs demonstrated greater phosphatidylserine exposure (annexin V) and microparticle shedding but similar P‐selectin (CD62P) abundance compared to CPPs. UVC‐CPPs displayed similar functionality to CPPs when assessed using aggregometry, thromboelastography, and thrombin generation. CONCLUSIONS This study demonstrates the feasibility of cryopreserving UVC‐PI–treated PLT products. UVC‐PI treatment may increase the susceptibility of PLTs to damage caused during cryopreservation, but this is more pronounced during postthaw storage at room temperature.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.