Platelet membrane glycoproteins in thrombasthenia, Bernard-Soulier syndrome, and storage pool disease

Abstract

Quantitative polyacrylamide gel electrophoresis has been carried out on patients with Bernard-Soulier syndrome, Glanzmann's thrombasthenia, and storage pool defect in order to clarify the abnormalities in their platelet membrane glycoproteins. Normal individuals had values (expressed as PAS staining units/mg of membrane protein) of 5.11 +/- 0.63 for glycoprotein 1 (Mr 150,000), 2.35 +/- 0.35 for glycoprotein II (Mr 120,000), 0.89 +/- 0.22 for glycoprotein III (Mr 100,000), and 1.34 +/- 0.64 for glycoprotein IV (Mr 85,000). Total PAS staining of these four major bands was 9.70 +/- 1.26 PAS units/mg of membane protein. Patients with Bernard-Soulier syndrome completely lacked glycocalicin and had about one half (1.90 PAS units/mg) of the glycoprotein I of normal controls. These was no significant reduction in glycoproteins II, III, and IV, but total PASstaining 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 one family which showed, in addition, small platelets and an associated lipid defect. In thic case of glycoprotein (2.71) was significantly elevated.