In vitro platelet function of platelet concentrates prepared using three different apheresis devices determined by impedance and optical aggregometry

BACKGROUND: Testing the functional capacity of platelets (PLTs) from platelet concentrates (PC) is a main issue in transfusion medicine. Therefore, the aim was to study agonist-inducible PLT aggregation of PLTs obtained by three apheresis devices. A semiautomated impedance aggregometry-based whole-blood method (multiplate electrode PLT aggregometry MEA]) was modified for the use of PLTs from PC and data were compared with light transmission aggregometry (LTA).
STUDY DESIGN AND METHODS: PLT function was determined in 135 PCs without reconstitution with red blood cells (RBCs), obtained by three devices: Amicus, Trima Accel collection system, and MCS+. PLT function was assessed by the Multiplate TRAP test, and the area under the curve (AUC) was quantified. TRAP-6–inducible maximal PLT aggregation (MA%) by LTA was used for analyses.
RESULTS: The AUC was significantly lower in the Amicus PLTs compared to the Trima and MCS+ PLTs (Amicus versus Trima, p = 0.007; Amicus versus MCS+, p < 0.001). The Amicus PLTs were significantly less responsive to TRAP-6–inducible PLT aggregation than Trima (p = 0.002) or MCS+ PLTs (p < 0.001) by LTA, and Trima PLTs responded significantly less than MCS+ PLTs (p = 0.001). There was only a weak correlation between MEA and LTA (r = 0.29, p = 0.019).
CONCLUSION: PLTs obtained by the Amicus system show significantly less aggregation response to thrombin receptor stimulation compared to those obtained with other cell separators, examined by MEA and LTA. Testing PLT function in PCs by the MEA is a simple and rapid method without the need of adding RBCs. However, LTA and MEA appear to measure different aspects of PLT function.