PLATELET MEMBRANE-GLYCOPROTEINS IN THROMBASTHENIA, BERNARD-SOULIER SYNDROME, AND STORAGE POOL DISEASE

Abstract

Quantitative polyacrylamide gel electrophoresis was carried out on patients with Bernard-Soulier syndrome, Glanzmann''s thrombasthenia and storage pool defect to clarify the abnormalities in their platelet membrane glycoproteins. Normal individuals had values (expressed as PAS [periodic-acid Schiff] staining units/mg of membrane protein) of 5.11 .+-. 0.63 for glycoprotein I (MW 150,000), 2.35 .+-. 0.35 for glycoprotein II (MW 120,000), 0.89 .+-. 0.22 for glycoprotein III (MW 100,000), and 1.34 .+-. 0.64 for glycoprotein IV (MW 85,000). Total PAS staining of these 4 major bands was 9.70 .+-. 1.26 PAS units/mg of membrane protein. Patients with Bernard-Soulier syndrome completely lacked glycocalicin and had about 1/2 (1.90 PAS units/mg) of the glycoprotein I of normal controls. There was no significant reduction in glycoproteins II, III, and IV, but total PAS staining was reduced to 4.40 units/mg, reflecting the importance of the contribution of glycoprotein I to this parameter. Thrombasthenic platelets gave values for glycoprotein II of 0.66, which were about 25% of controls, and the values for glycoprotein III (0.34) were about 40% of controls. Patients with storage pool disease gave values within the normal range with the exception of 1 family which showed, in addition, small platelets and an associated lipid defect. In this case of glycoprotein IV (2.71) was significantly elevated.