Platelet concentrates prepared and stored under currently optimal conditions: minor impact on platelet adhesive and cohesive functions after storage

Abstract

Volume 39, September 1999 TRANSFUSION 951 BACKGROUND: The effect on platelets of two standard methods of platelet concentrate (PC) preparation was studied by flow cytometry. The findings were correlated with those obtained in an experimental in vitro perfusion model. STUDY DESIGN AND METHODS: PCs were prepared from whole blood by the platelet-rich plasma (PRP) or buffy coat (BC) method and placed on a flatbed platelet agitator at 22°C for up to 5 days. Platelet glycoproteins (GP)Ibα, GPIIb/IIIa, and GPIV, p-selectin and lysosomal integral membrane protein, and the binding of von Willebrand factor, fibrinogen, fibronectin, and coagulation factor Va were measured with the corresponding specific conjugated antibodies. Perfusions were carried out in an annular chamber with citrated blood depleted of platelets and white cells by filtration, to which samples from PCs were added. RESULTS: PRP-PC production provoked intense platelet activation. In contrast, in BC-derived PCs, platelet activation was milder, and only a significant increase in bound fibrinogen was seen. After 1 day of storage, differences between the methods that had been observed immediately after separation had almost disappeared. During the remaining storage period, increases in activation-dependent antigens and in procoagulant activity were measured. Of the studied platelet GPs, only GPIIb/ IIIa decreased by 25 percent in PRP-PCs. Differences in covered surface were not significant in perfusion studies performed on Day 0 and after 5 days of storage in PRP-PCs (26.8 ± 6.9 vs. 20.5 ± 5.8) or BC-PCs (23.8 ± 11 vs. 24.8 ± 10.2). CONCLUSION: Platelet activation occurred during the separation and storage of PCs prepared by both methods, and it was higher in PRP-PCs only in samples obtained immediately after preparation. Despite these changes, platelet adhesive and cohesive functions were similar in both types of PCs and remained basically unchanged after storage. ABBREVIATIONS: BC = buffy coat; FITC = fluorescein isothiocyanate; GP(s) = glycoprotein(s); LIMP = lysosomal integral membrane protein; MFI = mean fluorescence intensity; MoAb(s) = monoclonal antibody(ies); PC(s) = platelet concentrate(s); PE = phycoerythrin; PRP = platelet-rich plasma; vWF = von Willebrand factor.From the

Redistribution and Hemostatic Action of Recombinant Activated Factor VII Associated with Platelets

“…Labeled platelets were analyzed using dual-color labeling as described previously. 32 Platelets were differentiated by their characteristic forward versus side scatter. Histograms were generated with fluorescence data obtained in the logarithmic mode from 10,000 events analyzed in each sample.…”

Efeito da utilização de plasma rico em plaquetas na osteointegração dos enxertos ósseos homólogos criopreservados: estudo histomorfométrico em coelhos

“…No entanto, os efeitos mais expressivos no processo de cicatrização e osteogênese são encontrados no uso das duas substâncias associadas. Lind et al (1996) (Marx, 1998;Anitua, 1999;Lozano et al, 1999;Okuda et al, 2003).…”

“…(Marx, 1998;Anitua, 1999;Lozano et al, 1999;Sonnleitner et al, 2000;Kim et al, 2001;Lemos et al, 2002;Aghaloo et al, 2002;Okuda et al, 2003).…”

“…O plasma autólogo rico em plaquetas é um hemoderivado atóxico, não imunorreativo, obtido através de técnicas simplificadas de seqüestração e concentração de plaquetas após múltiplas centrifugações de amostras sanguíneas. É descrito como um método de baixo custo e aplicação clínica muito factível (Marx, 1998;Anitua, 1999;Lozano et al,1999;Okuda et al, 2003).…”

Stability of Soluble Adhesion Molecules, Selectins, and C-Reactive Protein at Various Temperatures: Implications for Epidemiological and Large-Scale Clinical Studies

“…Previous studies have not systematically examined effects on these markers of different storage temperatures, duration of storage, freeze-thaw cycles, or delays in separating plasma from whole blood (1)(2)(3)(4)(5). Venous blood samples were obtained from 10 nonsmoking healthy staff members (7 male, 3 female, age 24 -58 years) who had given informed consent.…”