SINGLE-DONOR PLATELET CONCENTRATES - CHANGES OF SURFACE GLYCOPROTEINSDURING STORAGE

Storage of single-donor platelet concentrates is currently limited to 5 days. During this period, however, numerous morphologic and biochemi cal changes have been observed. These changes result in functional imp airment of stored platelets. The present study describes increased bin ding of a monoclonal antibody against GMP 140 on the surface of stored single-donor platelets revealing an activation process. In contrast, binding of monoclonal antibodies directed against glycoprotein complex (GP) IIb-IIIa and ligand-induced binding site (LIBS1) is slightly dim inished during storage. When platelets are stimulated with ADP GMP 140 , GP IIb-IIIa, and LIBS1 are expressed to a higher extent than on the surface on nonstimulated platelets. The quantity exposed, however, dep ends upon the storage time. It is significantly reduced when platelets are stored for longer than 1-2 days. The present data indicate that s torage of single-donor platelet concentrates affects fibrinogen bindin g, cell to cell cohesion, and release reaction. The results are in goo d agreement with conventional aggregation and in vitro bleeding time m easurements.