Monitoring of platelet morphology during storage of platelet concentrates

Abstract

During storage, human platelet concentrates progressively lose the capacity to survive and function in vivo after transfusion. A shape transformation from disc to sphere is the most reliable in vitro determinant for the loss of the in vivo survival of platelets. To find an objective measurement for platelet morphology, we studied the effect of anticoagulant, temperature, and storage on the apparent median platelet volume (MPV) as determined by a particle counter and on changes in platelet shape as measured and by light microscopy. Changes in MPV, light transmission, and morphology score by light microscopy were observed within 1 minute after collection of blood in CPDA. As compared to blood immediately fixed on withdrawal, in CPDA blood, the MPV increased from 4.1 to 5.7 fl, and light transmission difference decreased from 22 to 7 percent. A partial restoration of these determinants was found when the whole blood was incubated for 30 minutes at 37 degrees C, before preparation of platelet-rich plasma. In the first 5 days of platelet storage, the MPV increased from 4.6 to 5.0 fl; thereafter, it started to decrease. An increase in fragmented platelets after 5 days was observed on light microscopy. The light transmission difference showed a slow disc-to-sphere transformation during storage. This transformation accelerated from Day 5 to Day 7; after 11 days, only spheres were detected. After 7 days the swirling pattern scores were still in accordance with the presence of discs, whereas the other structure-associated determinants showed already spheric and even fragmented platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Usefulness of delta value of platelet parameters on ADVIA 120 for the functional reactivity of stored platelets

“…The MPV (22), PCDW (23), and MPC (24) platelet parameters, determined by a hematology analyzer, have been reported to reflect the storage lesion of the platelets to be used for transfusions. We evaluated whether ADP stimulation of the platelets could induce changes in the volume, granulation, and shape distribution of the stored platelets, and the degree of such changes might be associated with the functional reactivity of stored platelets to ADP.…”

On the interaction of IgG subclasses with the low affinity Fc gamma RIIa (CD32) on human monocytes, neutrophils, and platelets. Analysis of a functional polymorphism to human IgG2.

“…Platelets were then concentrated by centrifugation (7 min, 1,200 g) and three washes were performed with PBS/5 mM EDTA/0.5% FCS (26). PMN expressing reduced levels of FcyRIII were isolated from two patients with diagnosed paroxysmal nocturnal hemoglobinuria (PNH) (27,28).…”

Morphological evaluation of canine platelets on Giemsa- and PAS-stained blood smears

“…As there are only few detailed descriptions about the light-microscopic morphology of canine platelets (Bessis, 1972;Yamashiro et al, 1983;Jain, 1986;Keller, 1986;Fijnheer et al, 1989;Hopper et al, 1989;Tablin et al, 1989;Jain, 1993;Reagan et al, 1998;Cowell et al, 1999), our goal was to investigate canine thrombocytes on Giemsa-and PAS-stained smears in healthy animals and in dogs with pathological conditions. 340 HALMAY et al…”