Detection of platelet activation with monoclonal antibodies and flow cytometry. Changes during platelet storage

Abstract

To investigate whether changes in platelet condition during platelet storage correlate with an altered expression of platelet membrane proteins, the binding of monoclonal antibodies (MoAbs) to fresh platelets was compared with MoAbs' binding to thrombin-activated platelets and to platelets stored as platelet concentrates. The MoAbs included antibodies against the platelet glycoprotein (GP) IIb/IIIa complex and against two activation-dependent antigens, one of which was a component of the internal platelet alpha-granule membrane (GMP 140) and the other of which was a 53-kD protein derived from platelet lysosomes. The binding of MoAbs to platelets fixed with 1 percent paraformaldehyde was measured by flow cytometry. In thrombin-activated platelets, a threefold increase was found in the expression of GP IIb/IIIa over that in fresh platelets. The binding of the activation-dependent MoAbs increased from 2 to 3 percent to 70 to 80 percent of the platelets. Storage of platelet concentrates for 5 days resulted in a 60 percent increase in GP IIb/IIIa expression compared to Day 0 and increased binding of the MoAbs directed against GMP-140 from 3 to 16 percent and against the 53-kD protein from 2 to 8 percent of the platelets, respectively. These changes correlated with modifications in platelet morphology (decrease in swirling), leakage of lactate dehydrogenase, and release of beta-thromboglobulin. These data indicate that platelets become activated and are damaged during the storage of platelet concentrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Quality control of riboflavin-treated platelet concentrates using Mirasol® PRT system: Polish experience

“…28 Fijnheer et al observed that P-selectin expression correlates with the PC platelet count. 29 According to his observations, after 5 days of storage, a 15% increase in the number of activated platelets occurred if the platelet count was below 1 × 10 9 /mL, and a 30% increase occurred if the platelet concentration was above 1.4 × 10 9 /mL. In our study, we observed minimal platelet activation (higher P-selectin expression) on storage day 5 for PRT-treated PCs, though the values were not statistically significant compared to control PCs.…”

Effects of cytarabine and various anthracyclins on platelet activation: Characterization of in vitro effects and their possible clinical relevance in acute myelogenous leukemia

“…This close contact between AML blasts and platelets may thereby form a basis for functional interactions between these cells. 28,41,43,44,57 Various methods for detection of peripheral blood platelet activation and platelet-leukocyte adhesion have been described previously, 31,39,40,45,46 and most of these methods include platelet fixation to avoid ex vivo activation. Fixation procedures themselves may induce platelet activation, however, although this does not seem to occur when using low paraformaldehyde concentrations.…”

Activation during preparation of therapeutic platelets affects deterioration during storage: a comparative flow cytometric study of different production methods

“…PS expression can be identified by increased binding of fluorescein-labelled Annexin V, which binds preferentially to negatively charged phospholipids (Tait et al, 1989). Previous studies have demonstrated increased levels of bound fibrinogen (Goodall, 1991) and P-selectin expression (George et al, 1988;Fijnheer et al, 1990a;Rinder et al, 1991Rinder et al, , 1993Pedigo et al, 1993) in platelet concentrates, platelet microparticles (George et al, 1988) and decreased expression of the GPIb-IX complex (George et al, 1988;Bertolini et al, 1990;Bode, 1990;Ribeiro et al, 1992;Rivera et al, 1994), but total GPIIb-IIIa expression has been reported to be raised (Fijnheer et al, 1990) or unchanged (George et al, 1988;Rinder et al, 1993;Ribeiro et al, 1992;Rivera et al, 1994).…”