Soluble platelet glycoprotein V in distinct disease states of pathological thrombopoiesis.

Quantitative platelet disorders (i.e., thrombocytosis or thrombocytopenia) may also be associated with qualitative platelet alterations. Clonal thrombocythemia (CT), reactive thrombocytosis (RT), immune thrombocytopenic purpura (ITP), and thrombocytopenia of aplastic pancytopenia (AA) or infiltrative bone marrow disorders represent the major classes of pathological thrombopoiesis. Glycoprotein V may serve as an in vivo marker of platelet activation in thrombotic and hemorrhagic states. The aim of this study was to assess circulating plasma soluble platelet glycoprotein V (sGPV) concentrations in distinct disease states of pathological thrombopoiesis. The whole study group comprised 20 patients with thrombocytopenia, 32 patients with thrombocytosis and 14 healthy adults as the control group. sGPV was significantly increased in the group of thrombocytosis patients in comparison to the thrombocytopenic group and the healthy control groups. When sGPV levels were corrected according to platelet number (sGPV/tr), this ratio was very high in patients with thrombocytopenia compared to patients with thrombocytosis and the control group. Our results suggest that there is an ongoing platelet activation associated with thrombocytosis regardless of its origin is either CT or RT. Therefore, glycoprotein V system may serve to activate residual platelets in thrombocytopenia regardless of its origin is either ITP or AA.