Analysis of Platelet Membrane Glycoproteins in Myeloproliferative Disorders

Abstract

In myeloproliferative disorders, bleeding tendency and thrombosis were encountered occasionally, in the presence of extremely high platelet counts. Platelet membrane glycoproteins as receptor sites were studied by SDS disc electrophoresis and two dimensional electrophoresis in chronic myelogenous leukemia (CML, 7 cases), polycythemia vera (PV, 2 cases), primary thrombocythemia (PT, 2 cases) and myelofibrosis (MMM, 1 case). In CML group any band of abnormal molecular size was not found but the percent of GP I to all PAS stained peaks was reducedd and GP III was increased statistically. Four peaks labelled with 125I-Na by lactoperoxidase were appeared in accordance with PAS staining in these disorders.In GP I peak, the 125I incorporation rate was not different between normal and myeloproliferative disorders. The percent of PAS staining intensity was decresed in CML but increased in PT, PV and MMM. In GP III peak of CML, the increased percent of PAS staining and the decreased 125I incorporation rate were proved compared to the control. In MMM, PV and PT, it was shown that intensity percent of PAS staining was normal but 125I incorporation rate was decreased against GP III.To analyse the dissociation between PAS stain and 125I incorporation rate, the two dimensional electrophoresis was conduced with non reduced-reduced system. The autoradiographic pattern of this electrophoresis showed seven 125I incorporated spots (GP Ia, Ib, Ic, IIa, IIb, III and IV) in normal. The GP Ib was showed as an unclear spot and GP IV was divided in two spots in 4 of 6 CML cases. The GP IV appeared as a faint spot in two PT cases. In MMM and PV, the autoradiographic patterns were similar to those of CML cases.Association of these findings in surface glycoproteins with abnormalities of epinephrine and collagen induced aggregation in these disorders are under investigation.