Correlation between in vitro aggregation and thromboxane A2 production in fresh, liquid-preserved, and cryopreserved human platelets: effect of agonists, pH, and plasma and saline resuspension

• Published in: Transfusion (Philadelphia, Pa.) Vol. 45; no. 4; pp. 596 - 603
• Main Authors: Valeri, C.R., Macgregor, H., Ragno, G.
• Format: Journal Article
• Language: English
• Published: Oxford, UK and Malden, USA Blackwell Science Inc 01-04-2005; Blackwell Publishing
• Subjects: Adenosine Diphosphate - pharmacology; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Arachidonic Acid - pharmacology; Biological and medical sciences; Blood coagulation. Blood cells; Blood Platelets - cytology; Blood Platelets - metabolism; Blood Preservation; Blood. Blood and plasma substitutes. Blood products. Blood cells. Blood typing. Plasmapheresis. Apheresis; Blood. Blood coagulation. Reticuloendothelial system; Cryopreservation; Fundamental and applied biological sciences. Psychology; Humans; Hydrogen-Ion Concentration; In Vitro Techniques; Medical sciences; Molecular and cellular biology; Pharmacology. Drug treatments; Plasma; Platelet; Platelet Aggregation - drug effects; Platelet Aggregation - physiology; Platelet Transfusion; Sodium Chloride; Thromboxane A2 - metabolism; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Aggregation; Human; Platelet; Transfusion; Arachidonic acid derivatives; Eicosanoid; Thromboxane A2; pH
• ISSN: 0041-1132; 1537-2995
• DOI: 10.1111/j.0041-1132.2005.04291.x

BACKGROUND: Some of the tests used to assess the quality of fresh and preserved platelets (PLTs) include PLT number, PLT morphology, pH of the PLT medium, PLT response to hypotonic stress, and PLT aggregation to agonists. This study was performed to assess the function of fresh and preserved PLTs by their response to aggregation and their production of thromboxane A2 after in vitro stimulation with agonists.
STUDY DESIGN AND METHODS: PLTs isolated by apheresis procedures were stored at 22°C for as long as 5 days and then frozen with 6 percent dimethyl sulfoxide, stored at −80°C, thawed, washed, and resuspended in medium. The effects of agonists and the pH and composition of the medium on PLT aggregation and PLT production of thromboxane A2 after stimulation were measured.
RESULTS: The agonists and the pH and composition of the medium affected both the aggregation response and the production of thromboxane A2 by the fresh and preserved PLTs. PLT aggregation response to arachidonic acid (AA) and adenosine diphosphate (ADP) was significantly lower in the cryopreserved PLTs than in the fresh and preserved PLTs. After stimulation with AA and ADP, the cryopreserved PLTs produced more thromboxane than did the fresh and liquid‐preserved PLTs.
CONCLUSIONS: The agonists and the pH and composition of the medium affected the response to aggregate and produce thromboxane in vitro in both the fresh and the liquid‐preserved PLTs. PLT thromboxane A2 production may be a better in vitro test than PLT aggregation to assess PLT function in vivo.