Paper| Volume 37, ISSUE 6, P659-668, March 15, 1985

Destruction of ristocetin cofactor by coagulation at 4°C

      This paper is only available as a PDF. To read, Please Download here.


      Ristocetin cofactor (VIIIR:RCo) and factor VIII-related antigen (VIIIR:Ag) were measured in anticoagulated and non-anticoagulated blood incubated at 4°C, room temperature (RT) or 37°C for 24 hours. A marked decrease in VIIIR:RCo, to almost undetectable levels, and a smaller decrease in VIIIR:Ag occurred when whole blood clotted at 4°C. These changes were slight 8r absent when blood clotted at RT or 37°C. VIIIR:RC8 lost at 4°C was not recoverable by further incubation at 37°C but the less-marked loss of VIIIR:Ag was partially recovered. In blood which had clotted at 4°C there was a change in the electrophoretic profile of VIIIR:Ag on crossed immunoelectrophoresis: there was more anodal migration of the VIIIR:Ag peak, consistent with a decrease in the mean molecular size. Further experiments showed that the decrease in VIIIR:RCo during coagulation at 4°C preceded the decrease in fibrinogen levels. In cell-free plasma VIIIR:RCo also decreased markedly when coagulation occurred at 4°C. The results show that loss of VIIIR:RCo occurs when blood is allowed to clot at 4°C: this is not due to cryoprecipitation and does not require the presence of blood cells. The data suggest that it is probably caused by plasma proteases activated early in the coagulation pathway.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Thrombosis Research
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Hondow J.A.
        • Russell W.J.
        • Tunbridge L.J.
        • Lloyd J.V.
        Stability of von Willebrand factor in blood stored at 4°C.
        Thrombosis Res. 1982; 27: 125-130
        • Nilsson I.M.
        Report of the working party on factor VIII-related antigens.
        Thrombos. Haemostas. 1978; 39: 511-520
        • Weiss H.J.
        • Hoyer L.W.
        • Rickles F.R.
        • Varma A.
        • Rogers J.
        Quantitative assay of a plasma factor deficient in von Willebrand's disease that is necessary for platelet aggregation.
        J. Clin. Invest. 1973; 52: 2708-2716
        • MacFarlane D.E.
        • Stibbe J.
        • Kirby E.P.
        • Zucker M.B.
        • Grant R.A.
        • McPherson J.
        A method for assaying von Willebrand factor (ristocetin cofactor).
        Thrombos. Diathes. Haemorrh. 1975; 34 (letter): 306-308
        • Rudzki Z.
        • Tunbridge L.J.
        • Lloyd J.V.
        A new simple assay for factor VIII related antigen.
        Thrombosis Res. 1979; 16: 577-586
        • Laurell C-B.
        Antigen-antibody crossed electrophoresis.
        Anal. Biochem. 1965; 10: 358-361
        • Vermylen C.
        • De Vreker R.A.
        • Verstraete M.
        A rapid enzymatic method for assay of fibrin polymerization time (FPT Test).
        Clin. Chim. Acta. 1963; 8: 418-424
        • Zimmerman T.S.
        • Roberts J.
        • Edgington T.S.
        Factor-VIII-related antigen: Multiple molecular forms in human plasma.
        in: Proc. Nat. Acad. Sci.72. 1975: 5121-5125
        • Atichartakarn V.
        • Marder V.J.
        • Kirby E.P.
        • Budzynski A.Z.
        Effects of enzymatic degradation on the subunit composition and biologic properties of human factor VIII.
        Blood. 1978; 51: 281-297
        • Pasquini R.
        • Hershgold E.J.
        Effects of plasmin on human factor VIII (AHF).
        Blood. 1973; 41: 105-111
        • Kopec M.
        • Bykowska K.
        • Lopaciuk S.
        • Jelenska M.
        • Kaczanowska J.
        • Sopata I.
        • Wojtecka E.
        Effects of neutral proteases from human leukocytes on structure and biological properties of human factor VIII.
        Thrombos. Haemostas. 1980; 43: 211-217
        • Hara A.
        • Matsunaga M.
        • Yamamoto J.
        • Morimoto K.
        • Nagai H.
        • Kanatsu K.
        • Pak C.H.
        • Ogino K.
        • Kawai C.
        Cryoactivation of plasma renin.
        Clin. Sci. Molec. Med. 1978; 55: 139s-141s
        • Palmer R.N.
        • Gralnick H.R.
        Cold-induced contact surface activation of the prothrombin time in whole blood.
        Blood. 1982; 59: 38-42