Summary. A glycoprotein abnormality in membrane fractions isolated from the platelets of patients with Glanzmann's thrombasthenia is described. Glycoproteins solubilized from thrombasthenic and control human platelets have been compared by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. Whereas in a control human platelet membrane fraction three major glycoproteins of molecular weight 155 000, 135 000 and 103 000 were observed, in a similar fraction from thrombasthenic platelets a glycoprotein of 152 000 molecular weight predominated. No differences were observed in the nature of a high molecular weight acidic glycopeptide released from washed thrombasthenic and control platelet suspensions by trypsin, and the sialie acid content of thrombasthenic platelets was shown to be within the normal range.It is suggested that the glycoprotein abnormality may be due to an altered organization within the thrombasthenic platelet membrane and that further studies are necesasry to investigate the role of membrane glycoproteins in platelet function.
VON WILLEBRAND'S disease is a constitutional haemorrhagic diathesis, inherited as a simple Mendelian dominant and characterized by a prolonged bleeding time and a deficiency of Factor VIII (antihaemophilic globulin). It it sometimes referred to as angio-haemophilia, pseudo-haemophilia or vascular haemophilia.The pathogenetic mechanisms involved in this disorder have been investigated by Nilsson, Blomback and their collaborators (Nilsson, Blomback and von Francken, 1957;Nilsson, Blomback, Jorpes, Blomback and Johansson, 1957; Nilsson, Blombiick and BlombHck, 1959).They found that the infusion of Fraction 1-0, prepared by the method of BlombZck and Blombick (1956) from either normal or haemophilic plasma, corrected the bleeding time of patients with von Willebrand's disease. Furthermore, the results of transfusion experiments suggest that the Factor-VIII deficiency of von Willebrand's disease differs in its cause from that of haemophilia.Our previous work (Cornu, Larrieu, AIagille and Bernard, 1959; Bernard, 1960, 1961) has partially confirmed the results of Nilsson and her colleagues, but we obtained an inconsistent effect on the bleeding time after the transfusion of Fraction I, prepared by Cohn's procedure. This paper presents the results of transfusion of fresh normal or haemophihc blood or plasma in patients with von Willebrand's disease. MATERIALS AND METHODSBleeding times were performed by Duke's method (normal range up to 4 minutes) and by Capitlaryjugility was determined by a negative pressure method (normal range over 15 cm.Platelet counts were carried out by phase contrast using a 3 per cent procaine solution asThe whole blood clotting time was determined by the method of Lee and White (1913).The prothrombin consumption test of Soulier (1948) was used (normal range over 50 seconds).Factor VIII was assayed on BaS04-adsorbed oxalated plasma by the method of Biggs, I. Factor V was prepared by the fractionation procedure described by Biggs and Mac-2. Phospholipid. The chloroform brain extract of Bell and Alton (1954) was used.3. Serum was obtained from blood collected into human brain thromboplastin (I in ~o o ) , incubated at 37' C. for 4 hours and centrifuged at high speed for 10 minutes. It contained no detectable prothrombin, as determined by a one-stage assay system. Ivy's method (normal range up to 8 minutes). Hg). diluting fluid. Evebng and Richards (1955), with the following modifications: farlane (1957), from BaCOs-adsorbed ox serum. * Research Associate, Institut National d'Hygi&ne (Professor L. Bugnard). t Postal address: Hdpital Saint-Louis, 2 Place du Docteur-Fournier. Paris, X. I R. J.Fresh platelets were concentrated from 5 pints of blood, collected into disodium EDTA at a final concentration of 0.18 per cent (w/v) in siliconized containers. The maximum interval between collection of blood and platelet infusion was 3 hours. CASE RECORDSTen patients received infusions of blood or plasma; most of the cases have been previously reported (Cornu et al., 1961).Case I , a man aged 32, has had a ha...
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