Interactions of oversulfated chondroitin sulfate (OSCS) from different sources with unfractionated heparin
Research article published in Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/Hemostasis (2012)
Abstract
In 2008, oversulfated chondroitin sulfate (OSCS) was identified as the main contaminant in recalled heparin. Oversulfated chondroitin sulfate can be prepared from bovine (B), porcine (P), shark (Sh), or skate (S) origin and may produce changes in the antithrombotic, bleeding, and hemodynamic profile of heparins. This study examines the interactions of various OSCSs on heparin in animal models of thrombosis and bleeding, as well as on the anticoagulant and antiprotease effects in in vitro assays. Mixtures of 70% unfractionated heparin (UFH) with 30% OSCS from different sources were tested. In the in vitro activated partial thromboplastin time (aPTT) assay, all contaminant mixtures showed a decrease in clotting times. In addition, a significant increase in bleeding time compared to the control (UFH/saline) was observed. In the thrombosis model, no significant differences were observed. The OSCSs significantly increased anti-Xa activity in ex vivo blood samples. These results indicate that various sources of OSCS affect the hemostatic properties of heparin.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
In 2008, oversulfated chondroitin sulfate (OSCS) was identified as the main contaminant in recalled heparin.
Why This Matters for Hirudotherapy
This study mixed unfractionated heparin (70%) with 30% oversulfated chondroitin sulfate (OSCS) from bovine, porcine, shark, or skate sources and tested the blends in animal thrombosis and bleeding models plus in-vitro coagulation assays; the abstract reports that the contaminant mixtures shortened aPTT clotting times, significantly prolonged bleeding time versus control, raised anti-Xa activity ex vivo, and showed no significant difference in the thrombosis model, indicating OSCS from any source perturbs heparin's hemostatic properties. For the ASH evidence picture the connection is indirect: OSCS was the contaminant behind the 2008 recalled-heparin crisis, an episode often cited as motivation for non-heparin anticoagulant alternatives including the hirudin-derived direct thrombin inhibitor class. Honest caveat: this is a preclinical (animal plus in-vitro) study of heparin contamination and tests no medicinal-leech or hirudin-derived agent, so its bearing on hirudotherapy is contextual rather than direct, and animal/laboratory findings do not establish clinical effects.
Citation
Interactions of oversulfated chondroitin sulfate (OSCS) from different sources with unfractionated heparin
Gray A et al. · Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/Hemostasis, 2012
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