Background: Previous studies in a mouse model with “chilled” mouse platelets stored at 4°C for two hours with and without galactosylation showed protection against the adverse effects of chilling with galactosylation (

Science 2003;301:1531
). However, prior studies with human platelets demonstrated that the adverse effects of 4°C storage became irreversible only after 18 to 24 hours of 4°C storage (
J Lab Med 1978;6:971
). Therefore, we performed viability studies using human platelets stored for two days to exceed the period of potential reversibility of any cold-induced platelet injury.

Methods: Apheresis platelets were collected using Haemonetics MCS+ equipment from four normal volunteers. After collection, the platelets were pooled into one bag, and then the platelets were divided equally between two storage bags. Half of the platelets from each of the four collections were stored at 4°C with galactosylation, and the other half of the platelets were stored at 4°C without galactosylation (two collections) or at 22°C using standard storage conditions (two collections). After storage, samples from each of the two types of platelets stored from a volunteer were radiolabeled with either 51Cr or 111In, re-injected, and serial blood samples were drawn to determine post-transfusion recoveries and survivals of the radiolabeled autologous platelets.

Results: Results of the radiolabeled platelet studies are shown in the table.

In Vivo Radiolabeled Autologous Platelet Recoveries And Survivals

4°C GALACTOSYLATED PLATELETS4°C STORED PLATELETS22°C STORED PLATELETS
Normal VolunteerRecovery (%)Survival (Days)Recovery (%)Survival (Days)Recovery (%)Survival (Days)
1462.8482.9
2642.8582.8
46 2.2  59 6.8 
26 1.0  34 6.9 
Ave. ± 1 S.D. 46 ± 16 2.2 ± 0.9 53 ± 5 2.9 ± 0.1 47 ± 13 6.9 ± 0.1 
4°C GALACTOSYLATED PLATELETS4°C STORED PLATELETS22°C STORED PLATELETS
Normal VolunteerRecovery (%)Survival (Days)Recovery (%)Survival (Days)Recovery (%)Survival (Days)
1462.8482.9
2642.8582.8
46 2.2  59 6.8 
26 1.0  34 6.9 
Ave. ± 1 S.D. 46 ± 16 2.2 ± 0.9 53 ± 5 2.9 ± 0.1 47 ± 13 6.9 ± 0.1 

No adverse events were reported with the transfusion of the galactosylated platelets, there was no evidence of the development of anti-platelet antibodies against galactosylated or non-galactosylated platelets, and samples of the galactosylated platelets obtained after storage verified galactosylation of the platelets.

Conclusions: The data show that, following two days of 4°C storage, the recoveries and survivals of the galactosylated platelets are no different than the non-galactosylated 4°C stored platelets from the same volunteer. Although the recoveries of the 4°C stored platelets with and without galactosylation are well-maintained compared to the 22°C stored platelets, the survivals are markedly reduced as has been previously shown for 4°C stored platelets (

Br J Haematol 1976;34:403
).

Disclosures: Dr. Hans Wandall is employed by ZymeQuest, Inc.; Dr. Karin Hoffmeister has served as a consultant to ZymeQuest, Inc.; Dr. Hans Wandall has stock options in ZymeQuest, Inc.; ZymeQuest, Inc. provided support for the studies reported in the abstract.

Author notes

*

Corresponding author

Sign in via your Institution