Effects of prestorage white cell‐reduction of apheresis platelets on platelet glycoprotein Ib and von Willebrand factor

Abstract

Twenty plateletpheresis components were harvested from 11 healthy donors and stored in polyolefin bags on a horizontal flatbed agitator at 22 degrees C. After 24 hours, white cells were reduced in one aliquot by centrifugation while the other aliquot was stored unaltered. Samples were obtained aseptically from each of these platelets at intervals for up to 10 days, and measurements were made of platelet glycoprotein Ib (GPIb) by both flow cytometry and polyacrylamide gel electrophoresis, of ristocetin-induced platelet aggregation by impedance aggregometry, and of plasma and platelet von Willebrand factor (vWF) by enzyme-linked immunosorbent assay. Storage of platelets under these conditions was associated with only minor decreases in surface GPIb, intraplatelet vWF, and ristocetin-induced platelet aggregation, and no differences were observed between the white cell-reduced and nonreduced aliquots. No benefit of white cell reduction in such components before prolonged storage is evident in the vWF-platelet interaction.

Leukocyte Depletion and Storage of Single-Donor Platelet Concentrates

“…We con clude that the concentration of neutrophil granulocytes was about hundred times lower than 1,000/pl in our PCs. This would explain the absence of a beneficial effect of prestor age leukocyte depletion on poststorage platelet function in our investigation as well as in the papers mentioned above [18,23,28]. The authors of these studies did not perform differentials either, but we assume that the lymphocyteigranulocyte ratio in their PCs was similar to that observed in our laboratory.…”

“…We conclude that there is no ad vantage evident in terms of improved platelet quality for prestorage leukodepletion of PCs. This is in accordance with the results of other studies; neither Sweeney et al [28], who investigated apheresis platelet concentrates with a median leukocyte contamination of 2x 107 before filtration, nor Joustra-Dijkhuis et al [18], who examined platelet con centrates made from a pool of four buffy coats with a mean leukocyte contamination of 7.2xl06 before filtration, nor Garcia et al [23], who investigated apheresis platelets with a mean leukocyte contamination of 12.2 xlO8 could demon strate a beneficial effect of prestorage leukocyte depletion of PCs on poststorage platelet quality. In contrast to Dzik et al [14], who examined PRP with a much higher leukocyte mission in the turbidimetric assay.…”

“…There are several reports investigating the quality of pla telets after filtration and during subsequent storage in PCs manufactured from whole blood donations [14][15][16][17][18][19], but lit tle is known about the quality of platelets in single-donor PCs prepared by plateletpheresis under these conditions [20][21][22][23]. Due to the possibilities of modem cell separators the leukocyte contamination in unfiltered PCs has under gone a remarkable decrease and is now much lower com pared to those in PCs manufactured from buffy coat or pla telet-rich plasma (PRP).…”

Effect of Prestorage Leukocyte Reduction on Proteins of Platelets Obtained by Apheresis

“…Our results show that the binding of specific MoAbs to GPIb and GPIIb/IIIa was similar in NFPCs and FPCs and that it was stable during 7 days of storage. These results are in agree-ment with those of Garcia et al [29] who analyzed GPIb of stored apheresis platelets by sodium dodecyl sulfate PAGE. Other authors found a significant diminution of GPIb and a decrease of platelet responsiveness to ristoce tin in stored PCs enriched by relatively high amounts of neutrophils (1 x KT/ml) compared to platelet stored with out enrichment, but they failed to demonstrate such an effect in PCs enriched by lymphocytes (lxl01 2 3 4 5 6 7/ml) [30], Our results probably reflect the low leukocyte content in PCs prepared by the 'surge' technique.…”

Prevention of Cytokine Accumulation in Platelets Obtained with the COBE Spectra Apheresis System

“…Several investigators have shown that vWf is a substrate for leukocyte-derived proteases [64, 67]. Though platelet-derived vWf degrading proteases have been documented [68], Garcia et al [69]also showed that plasma vWf was stable in leukocyte-poor suspensions of platelets. This suggests that platelet-derived proteases do not play a significant role in vWf degradation under blood bank conditions.…”