title: Hirudin versus heparin for use in whole blood in vitro biocompatibility models.
abstract: Heparin has traditionally been a widely used anticoagulant in blood research, but has been shown to be inappropriate for work with the complement system because of its complement-interacting properties. In this work, we have compared the effects of heparin with those of the specific thrombin inhibitor hirudin on complement and blood cells in vitro. Whole blood collected in the presence of hirudin (50 microg/mL) or heparin (1 IU/mL) was incubated in the slide chamber model. The plasma was analyzed for complement activation markers C3a and sC5b-9, and the polyvinylchloride test slides were stained for adhering cells. The integrity of the complement system was tested by incubating serum and hirudin-treated plasma in the presence of various activating agents. In contrast to heparin, the addition of hirudin generally preserved the complement reactivity, and complement activation in hirudin plasma closely resembled that in normal serum. Importantly, immunochemical staining of surface-bound cells demonstrated the inducible expression of tissue factor on bound monocytes from hirudin-treated blood, an effect that was completely abolished in heparin-treated blood. Our results indicate that hirudin as an anticoagulant produces more physiological conditions than heparin, making hirudin well-suited for in vitro studies, especially those addressing the regulation of cellular processes.
authors.affiliation: School of Pure and Applied Natural Sciences, University of Kalmar, Kalmar, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Bexborn
authors.forename: Anna E
authors.initials: AE
authors.lastname: Engberg
authors.forename: Kerstin
authors.initials: K
authors.lastname: Sandholm
authors.forename: Tom Eirik
authors.initials: TE
authors.lastname: Mollnes
authors.forename: Jaan
authors.initials: J
authors.lastname: Hong
authors.forename: Kristina
authors.initials: K
authors.lastname: Nilsson Ekdahl
mesh_terms: D001672:Biocompatible Materials / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects; D002448:Cell Adhesion / Q000187:drug effects; D003167:Complement Activation / Q000187:drug effects; D015926:Complement C3a / Q000378:metabolism; D015938:Complement Membrane Attack Complex / Q000378:metabolism; D006493:Heparin / Q000494:pharmacology*; D006629:Hirudins / Q000097:blood / Q000494:pharmacology*; D006801:Humans; D007962:Leukocytes / Q000166:cytology / Q000187:drug effects; D008954:Models, Biological; D009000:Monocytes / Q000166:cytology / Q000187:drug effects; D011143:Polyvinyl Chloride / Q000494:pharmacology; D044967:Serum; D012995:Solubility / Q000187:drug effects; D013925:Thromboplastin / Q000378:metabolism
chemical_list: D001672:Biocompatible Materials; D015938:Complement Membrane Attack Complex; D006629:Hirudins; D015926:Complement C3a; D011143:Polyvinyl Chloride; D006493:Heparin; D013925:Thromboplastin