Refrigeration of apheresis platelets in platelet additive solution (PAS‐E) supports in vitro platelet quality to maximize the shelf‐life

Abstract

Background Refrigeration, or cold‐storage, of platelets may be beneficial to extend the limited shelf‐life of conventionally stored platelets and support transfusion protocols in rural and military areas. The aim of this study was to compare the morphologic, metabolic, and functional aspects of apheresis platelets stored at room‐temperature (RT) or cold conditions, in either plasma or supplemented with platelet additive solution (PAS). Study design and methods Double‐dose apheresis platelets were collected in either 100% plasma or 40% plasma/60% PAS‐E using the Trima apheresis platform. One component from each group was either stored at RT (20–24°C) or refrigerated (2–6°C). Platelets were tested over a 21‐day period. Results The platelet concentration decreased by approximately 30% in all groups during 21 days of storage (p > .05). Cold‐storage reduced glycolytic metabolism, and the pH was maintained above the minimum specification (>6.4) for 21 days only when platelets were stored in PAS. The surface phenotype and the composition of the supernatant were differentially affected by temperature and storage solution. Functional responses (aggregation, agonist‐induced receptor activation, clotting time) were improved during cold‐storage, and the influence of residual plasma was assay dependent. Conclusion In vitro platelet quality is differentially affected by storage time, temperature, and solution. Cold‐storage, particularly in PAS, better maintains key metabolic, phenotypic, and functional parameters during prolonged storage.

Gamma and X‐ray irradiation do not affect the in vitro quality of refrigerated apheresis platelets in platelet additive solution (PAS‐E)

“…Therefore, it is essential to understand the impact of irradiation when combined with cold storage, particularly given that other manufacturing variables, including platelet source (apheresis vs. whole-blood derived), storage solution (plasma vs. PAS) and pathogen inactivation, have been shown to affect the quality parameters of cold-stored platelets. 4,8,[22][23][24] In terms of logistics for the implementation of cold-stored platelets, this work demonstrates how irradiation fits into our current manufacturing practice. The platelet components were transported from our metropolitan donation centers to the processing center and refrigerated within 8 h of collection.…”

“…Importantly, in Australia, 100% of platelets are irradiated prior to issue to hospital sites, meaning that irradiation is a mandatory part of the manufacturing process. Therefore, it is essential to understand the impact of irradiation when combined with cold storage, particularly given that other manufacturing variables, including platelet source (apheresis vs. whole‐blood derived), storage solution (plasma vs. PAS) and pathogen inactivation, have been shown to affect the quality parameters of cold‐stored platelets 4,8,22–24 . In terms of logistics for the implementation of cold‐stored platelets, this work demonstrates how irradiation fits into our current manufacturing practice.…”

“…Cold storage alters many traditional in vitro indicators of platelet quality. Specifically, the morphology and metabolic profile of platelets are altered by cold storage 4,5 . Further, cold storage induces higher expression of activation markers, but reduces release of specific soluble mediators 5–7 .…”

“…Specifically, the morphology and metabolic profile of platelets are altered by cold storage. 4,5 Further, cold storage induces higher expression of activation markers, but reduces release of specific soluble mediators. [5][6][7] Importantly, the extent of these changes is influenced by the processing methods used to generate the platelet components, including the storage solution and the length of time the platelets are stored.…”

The Missing Pieces to the Cold-Stored Platelet Puzzle

“…One criticism for this work is that the CPs in 100% plasma were only stored for 3 days, making parallel comparison to day 19 CPs in PAS difficult. CPs stored in PAS-E in also maintained pH above 6.4 for 21 days [57]. The aggregation response to agonists is the same between CPs in PAS versus CPs in plasma.…”