Platelet adhesion changes during storage studied with a novel method using flow cytometry and protein-coated beads.

Area of Science:

• Hematology
• Biotechnology
• Analytical Chemistry

Background:

• Platelet concentrate (PC) quality assessment is crucial for transfusion medicine.
• Existing methods for evaluating platelet function during storage have limitations.
• A novel, efficient assay is needed to monitor platelet adhesion and activation.

Purpose of the Study:

• To develop and validate a new method for assessing platelet adhesion and activation.
• To utilize protein-coated polystyrene beads and flow cytometry for this purpose.
• To evaluate the method's utility in studying stored platelet concentrates.

Main Methods:

• Developed a flow cytometry assay using protein-coated beads (fibrinogen and collagen).
• Studied platelet concentrates (PCs) prepared by apheresis over 12 days of storage.
• Measured spontaneous and TRAP-6-induced platelet adhesion, P-selectin, and phosphatidyl serine (PS) expression.

Main Results:

• Platelet adhesion to fibrinogen beads increased by day 12; adhesion to collagen beads increased by day 7.
• TRAP-6 stimulation enhanced platelet adhesion, P-selectin, and PS exposure during the first 7 days.
• By day 12, TRAP-6 stimulation no longer significantly induced these changes, indicating functional decline.

Conclusions:

• The novel bead-based flow cytometry assay accurately assesses platelet adhesion and activation.
• The method can evaluate platelet function in stored PCs without red blood cells.
• This assay provides a valuable tool for transfusion medicine and other research settings.