Cryopreservation of canine platelets.
BACKGROUND
Platelet cryopreservation allows long-term storage and immediate availability of transfusion products.


OBJECTIVE
The addition of a preparation inhibiting platelet activation (Thrombosol, in 2% dimethyl sulfoxide [DMSO]) will enhance in vitro function and prolong in vivo survival of cryopreserved platelets compared with those preserved in 6% DMSO.


METHODS
Thirty-three research dogs.


METHODS
Prospective study. Eleven fresh canine apheresis platelet concentrates (PCs) were each split into 3 units: fresh and cryopreserved in 6% DMSO or Thrombosol. Platelet analysis, performed 1-10 weeks postfreezing, included in vitro functional testing and in vivo survival assessed by administration of biotinylated platelets.


RESULTS
Platelet aggregation was diminished in cryopreserved PC. Cryopreserved platelets could be activated, as based on mean thrombin-stimulated P-selectin expression (6% DMSO, 23.0%; Thrombosol, 18.4%), although to a lesser extent than fresh PC (49.1%) (P < .0001). The mean maximum in vivo platelet recovery for fresh PC was 80.3%, significantly greater than recovery for 6% DMSO (49.2%) and Thrombosol PC (43.7%) (P< or = .001). The half-life (days) of fresh PC (3.8 +/- 0.4) was significantly (P < .002) greater than that of 6% DMSO (1.9 +/- 1.0) and Thrombosol (2.4 +/- 1.1) PC, with no difference (P= .3) between cryopreserved PC.


CONCLUSIONS
Cryopreservation of canine platelets using Thrombosol did not provide any advantage over preservation using 6% DMSO. Cryopreserved platelets can be activated in vitro and provide therapeutic benefit when fresh platelets are unavailable. Further studies are needed to assess their in vivo hemostatic function.
Appleman
E H
EH
Schools of Veterinary Medicine and Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Sachais
B S
BS
Patel
R
R
Drobatz
K J
KJ
Groman
R P
RP
Kennedy
D R
DR
O'Donnell
P A
PA
Bryan
C
C
Callan
M B
MB
D000818:Animals; D001781:Blood Component Removal / Q000662:veterinary; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology*; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D003451:Cryoprotective Agents / Q000494:pharmacology; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004285:Dogs; D017713:Platelet Transfusion / Q000662:veterinary; D011446:Prospective Studies; D013997:Time Factors; D014021:Tissue Preservation / Q000379:methods*
D003451:Cryoprotective Agents; D004121:Dimethyl Sulfoxide