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Updated: Jun 12, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Antithrombin and heparin cofactor II-mediated inactivation of alpha-thrombin by a synthetic, sulfated mannogalactan
Ana Helena P Gracher1, Thales R Cipriani, Elaine R Carbonero
1Laboratório de Química de Carboidratos, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Paraná, Curitiba, Paraná, Brazil.
Introduction:
A mannogalactan from Pleurotus ostreatoroseus (MgPr) was chemically sulfated to give MgPr-S1, which was evaluated for its anticoagulant and antithrombotic activities, bleeding tendency, and platelet aggregation.
Materials And Methods:
MgPr-S1 was partially characterized by HPSEC-MALLS, methylation analysis, and 13C NMR spectroscopy. Its anticoagulant activity was determined by assays of aPTT, TT, alpha-thrombin and factor Xa residual activity, heparin cofactor II (HCII)-, or antithrombin (AT)-mediated inhibition. The antithrombotic effect was evaluated in rats using a venous thrombosis model and the bleeding tendency was also tested in vivo. Platelet aggregation was investigated by an adaptation of the method of Born [1].
Results:
The hydroxyl groups of beta-D-Manp units and OH-2 and OH-4 of the (1-->6)-linked alpha-D-Galp units were preferentially substituted. The anticoagulant activity of MgPr-S1 was mainly by thrombin inhibition with antithrombin and HCII, and had an effect on platelet aggregation induced by ADP and alpha-thrombin. It almost completely inhibited thrombus formation in vivo at a dose of 6 mg/kg and heparin inhibited thrombus formation at a dose of 0.200 mg/kg.
Conclusions:
These results suggested that the chemically sulfated mannogalactan could act as an alternative to heparin as anticoagulant.
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