Gray platelet syndrome (GPS) is an alpha granule
deficiency typically characterized by large platelets, mild to moderate thrombocytopenia, and bleeding caused by homozygous or compound heterozygous mutations in the NBEAL2.
A platelet alpha granule
membrane protein that is associated with the plasma membrane after activation.
While sCD40L and sPS are platelet function markers from membrane glycoproteins group, BT and PF4 are alpha granule
For example, the alpha granule
components, beta thromboglobulin and platelet factor 4.
Piccinini et al., "P latelet alpha granule
release in diabetes mellitus," Scandinavian Journal of Clinical & Laboratory Investigation, vol.
Flow cytometry studies have shown increased surface P-selectin, but decreased alpha granule
The alpha granule
storage pool disorder with large platelets is known as
(26) Platelets in the gray platelet syndrome, an alpha granule
deficit, are characteristic for being pale, gray, and hypogranular on a Wright-stained blood smear.
Therapeutic trial of autologous platelet-rich plasma in pigmentary disorder is a novel idea based on the fact that platelets contain many growth factors in their alpha granules
. These factors have established role in the process of tissue repair.
A possible explanation for this is that FV, in addition to circulating in plasma, is stored in platelet alpha granules
and is protected from circulating inhibitors.
STEM analysis of thrombocytes from control group showed the presence of microtubules and cell organelles, especially alpha granules
and dense granules (Figures 6(g) and 7(g)).
Since factor V, vWF and fibrinogen are also included in alpha granules
, some aggregation defect is also observed in specific deficiencies of these.