Repeatedly transfused thrombocytopenic patients frequently form antibodies directed against human leukocyte antigens (HLA) and become unresponsive to random donor platelet transfusions. Although exposure to foreign antigens borne on donor leukocytes appears necessary to provoke primary sensitization, the stability of leukocyte antigens during routine platelet storage is largely unknown. Accordi...

BACKGROUND The objective of this study was to determine the allowable platelet content limits for apheresis platelets stored for 7 days in a platelet storage bag (COBE ELP, Gambro BCT). METHODS Apheresis platelets under controlled concentration and volume per bag were stored in plasma up to 8 days at 22 degrees C with horizontal agitation. Routinely evaluated in vitro platelet parameters were...

D ESPITE the well-known susceptibility of platelets to damage on handling or storage comparatively little has been written about the changes which platelets undergo on incubation or storage. Nevertheless, numerous studies have been undertaken employing platelets incubated at 37 C. for various times to study certain aspects of their metabolism,’ or preincubating them with enzymes2 or radioisotop...

BACKGROUND Platelet indices are potentially useful markers for the early diagnosis of thromboembolic diseases. An increase in both mean platelet volume (MPV) and platelet distribution width (PDW) due to platelet activation, resulting from platelet swelling and pseudopodia formation was hypothesized. METHODS Platelet indices (MPV and PDW) in three groups of persons, using impedance and optical...

We have previously reported that ectopically expressed factor VIII (FVIII) is stored within platelets and is released upon platelet activation. Studies by others in various cell lines have suggested that having von Willebrand factor (VWF) coexpression is necessary for FVIII granular storage and for its secretion. We tested the importance of VWF coexpression for ectopic storage of FVIII in plate...

We have previously reported that ectopically expressed factor VIII (FVIII) is stored within platelets and is released upon platelet activation. Studies by others in various cell lines have suggested that having von Willebrand factor (VWF) coexpression is necessary for FVIII granular storage and for its secretion. We tested the importance of VWF coexpression for ectopic storage of FVIII in plate...

77 In contrast to the results of the study by Metcalfe et al., Costa et al. did not observe higher levels of P-selectin in PRP PCs than in BC-PC. However, the BC-PC may have been prepared in a different way. The cytokines measured are generally derived from white blood cells. The platelet units used in the present study were not leukocyte-reduced, suggesting that higher levels of leukocyte-deri...

Membranous microparticles (MP) appearing in the supernatant plasma of stored platelet concentrates (PC) were analyzed by flow cytometry. Two populations of MP were arbitrarily delineated by light scatter as larger or smaller than 0.5 micron fluorescent beads. An estimate of MP concentration was obtained by adding a known amount of fluorescent beads to each sample before analysis of a set number...