Preliminary characterization of the properties of cold‐stored apheresis platelets suspended in PAS‐III with and without an 8‐hour room temperature hold

Abstract

Background: Use of extended cold storage of platelets promises to increase PLT availability and the bacterial safety of bleeding patients. No information is currently available on the preservation of apheresis PLT in vitro quality parameters when PLTs are held at room temperature early in the storage period prior to transfer to cold storage. Study Design and Methods: Double units of platelets suspended in 35% plasma/65% PAS-III were collected from normal consenting research donors and rested at room temperature for 1-2 hours. One of the units was then stored at 1-6°C while the other unit was placed on an agitator at 20-24°C. Eight hours after collection, the unit stored at room temperature was transferred to 1-6°C storage without agitation. Units were sampled for an array of PLT in vitro parameters on Days 1, 7, 14, and 21. Results: As expected, PLTs held for 8 hours at 20-24°C prior to 1-6°C storage had greater lactate levels and reduced glucose levels and pH compared to PLTs subjected to a 1-2-hour room temperature hold prior to cold storage (P < .05). Unexpectedly, platelets held for 8 hours at room temperature had less aggregation response to collagen, ADP, and TRAP compared to PLTs held 1-2 hours at room temperature prior to cold storage (P < .05, n = 8). Conclusion: Decline of aggregation response should be considered when evaluating longer than necessary room temperature holds prior to cold storage of platelets.

Time from apheresis platelet donation to cold storage: Evaluation of platelet quality and bacterial growth

“…We conducted 12 different in vitro test for platelet components placed into cold storage 2 h post collection (control) compared to platelet components placed into the cold 8 h post collection (test) over 21 days of storage 22 . Eight matched pairs ( n = 8) were used for this evaluation, and the initial platelet yield for the split, paired units was 3.3 ± 0.3 × 10 11 .…”

“…Detailed methods for the characterization study were previously reported in Wagner et al 22 The following in vitro parameters were evaluated: platelet count, pH (37°C), glucose (mM), lactate (mM), CD62P+ (p‐selectin, %), CD42b (GP1bA, MFI), Annexin V (%), CM‐H2DCFDA (ROS, MFI), and aggregation (with 4 different agonist experiments).…”

“…The preliminary characterization study has previously been reported 22 and is reported here with updated post‐hoc analyses and discussions of the totality of the data along with new data on sterility.…”

“…Platelet surface markers and reactive oxygen species (ROS) markers including CD62P + PLT (p-selectin), CD42b (glycoprotein 1b alpha chain [GP1b-alpha]), Annexin V (phosphatidylserine exposure), and CM-H 2 DCFDA (reactive oxygen species [ROS] levels) were measured by flow cytometry (FACSCalibur, BD Biosciences) as previous described. 22,23…”

“…Statistical analyses were performed using GraphPad Prism (Version 9.0.1). Of note, the preliminary characterization data previously reported was analyzed GraphPad Instat 3 22 and confirmed with GraphPad Prism. Data are expressed as means ± standard deviation (SD).…”