BUFFY COAT PLATELETS STORED IN APYRASE, APROTININ, AND ASCORBIC-ACID IN A SUSPENDED BAG - COMBINED STRATEGIES FOR REDUCING PLATELET ACTIVATION DURING STORAGE

Background: Platelet activation is an important factor impeding the cl inical effectiveness of platelet transfusions. In this study, platelet concentrates (PCs) were prepared by a novel suspended-bag buffy coat technique that was followed by the addition of a mixture of platelet a ctivation inhibitors to the storage bag. Study Design and Methods: In vitro platelet function was evaluated in PCs prepared by the suspended -bag buffy coat technique and stored at 22 degrees C for 5 days in the presence (n=12) or absence (n=12) of apyrase, ascorbic acid, and apro tinin (AAA). Results: Platelets from AAA-incubated PCs demonstrated me an ATP levels 17 percent (p<0.004), 13 percent (p<0.02), and 22 percen t (p<0.003) higher than those measured in parallel control PCs on Days 1, 3, and 5, respectively. Similarly, on Days 3 and 5 of storage, res pectively, 45-percent (p<0.001) and 50-percent (p<0.001) greater ADP-i nduced maximum aggregation was observed in AAA-incubated PCs than was seen in control preparations. AAA-incubated PCs demonstrated alpha-gra nule membrane protein-140 expression 92 percent (p<0.01), 133 percent (p<0.003), and 104 percent (p<0.001) below that in control PCs on Days 1, 3, and 5, respectively. At similar intervals, a significant increa se in recovery from hypotonic shock also was observed in AAA-incubated PCs. Further, Day 5 AAA-PCs demonstrated significantly higher morphol ogy scores and O-2 consumption than did control preparations. Conclusi on: Buffy coat platelets prepared in suspended bags and stored in the presence of AAA demonstrate significantly reduced activation and enhan ced functional and metabolic activity.