Evidence that Platelet α-Granules Are a Major Determinant of Platelet Density: Studies in Storage Pool Deficiency

Summary

Density-related subpopulations of platelets were obtained by centrifuging platelets obtained from venous blood on a discontinuous gradient of arabinogalactan (Stractan). Four subpopulations were obtained in fractions of the gradient with densities ≤1.058, 1.065, 1.070, and 1.092 g/ml. The percentage of the total platelet population recovered in these various fractions in 5 patients with congenital storage pool deficiency who are deficient only in dense granules (δ-SPD) was similar to that observed in 8 normal subjects. In contrast, a shift in the density distribution towards a higher percentage of less dense platelets was observed in 3 patients (aδ-SPD) who are deficient in both a and dense granules. The results of these studies strongly suggest that agranules are a major determinant of platelet density.

Keywords

α-granules - platelet density

• References

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