Platelet function under high-shear conditions from platelet concentrates.
BACKGROUND
Platelet (PLT) collection and storage affect the functional capacity of PLTs in PLT concentrates (PCs). Therefore, PLTs' functional quality should be studied before transfusion.


METHODS
PCs (n = 15) were collected by a standard apheresis procedure (Trima, Gambro BCT) and were stored for 7 days. Samples were taken to assess PLT adhesion and aggregate formation by a cone and plate analyzer (Impact-R, DiaMed) on Days 1, 3, 5, and 7 after harvesting. This device allows testing PLT function under high-shear stress close to physiologic conditions. Concomitantly, P-selectin expression and the residual responsiveness to TRAP-6 were determined by flow cytometry.


RESULTS
PLT adhesion, as measured by surface coverage, decreased during the entire observation period; likewise, the size of aggregates was significantly lower on Days 5 and 7 compared to Day 1 (p < 0.02). P-selectin expression increased from Day 5 to Day 7 (p < 0.04), whereas TRAP-6-inducible expression remained stable until Day 5 of storage and decreased significantly on Day 7 (p = 0.04).


CONCLUSIONS
Our results show that high-shear-induced PLT adhesion and aggregation on the polystyrene surface deteriorate upon storage, suggesting decreased PLT function in vivo. Thus, the Impact-R may be a useful tool to assess the functional capacity of PLTs under various PLT harvesting and storage procedures.
Jilma-Stohlawetz
Petra
P
Department of Blood Group Serology and Transfusion Medicine and Clinical Pharmacology, Medical University of Vienna, Vienna, Austria. petra.jilma@meduniwien.ac.at
Horvath
Michaela
M
Eichelberger
Beate
B
Koren
Daniela
D
Jilma
Bernd
B
Panzer
Simon
S
D000328:Adult; D001792:Blood Platelets; D001793:Blood Preservation; D006801:Humans; D008297:Male; D008875:Middle Aged; D019007:P-Selectin / Q000032:analysis; D010446:Peptide Fragments / Q000032:analysis; D015539:Platelet Activation; D010973:Platelet Adhesiveness; D010974:Platelet Aggregation; D010979:Platelet Function Tests / Q000295:instrumentation* / Q000592:standards; D013314:Stress, Mechanical; D013997:Time Factors
D019007:P-Selectin; D010446:Peptide Fragments; C082835:thrombin receptor peptide (42-47)