title: Optimal heparin surface concentration and antithrombin binding capacity as evaluated with human non-anticoagulated blood in vitro.
abstract: Contact between blood and a biomaterial surface takes place in many applications and is known to activate the coagulation and complement systems. Heparin surface coatings have been shown to reduce blood activation upon contact with artificial surfaces. To establish the optimal heparin surface concentration, blood was incubated in a tubing loop model at 37 degrees C. The tubing was coated with different surface concentrations of heparin and rotated at three different velocities. We demonstrate that the blood compatibility of a surface with regard to coagulation, complement, and platelet activation can be improved by increasing the heparin surface concentration in the 6-12 pmol antithrombin/cm2 concentration interval. The binding of factor H is not influenced by the increased heparin surface concentration, suggesting that this factor is not the primary regulator of complement on heparin surfaces. In addition, the heparin coating has no effect on the complement activation that occurs on gas surfaces in extracorporeal circuits.
authors.affiliation: Department of Oncology, Radiology and Clinical Immunology, Section of Clinical Immunology, Rudbeck Laboratory C5, Uppsala University Hospital, SE-751 85 Uppsala, Sweden. jonas.andersson@klinimm.uu.se
authors.forename: Jonas
authors.initials: J
authors.lastname: Andersson
authors.forename: Javier
authors.initials: J
authors.lastname: Sanchez
authors.forename: Kristina Nilsson
authors.initials: KN
authors.lastname: Ekdahl
authors.forename: Graciela
authors.initials: G
authors.lastname: Elgue
authors.forename: Bo
authors.initials: B
authors.lastname: Nilsson
authors.forename: Rolf
authors.initials: R
authors.lastname: Larsson
mesh_terms: D000991:Antithrombins / Q000378:metabolism*; D001672:Biocompatible Materials / Q000378:metabolism*; D001769:Blood / Q000378:metabolism*; D001773:Blood Cells / Q000502:physiology; D002448:Cell Adhesion / Q000502:physiology; D017242:Complement Factor H / Q000378:metabolism; D006493:Heparin / Q000378:metabolism*; D006801:Humans
chemical_list: D000991:Antithrombins; D001672:Biocompatible Materials; C493495:CFH protein, human; D017242:Complement Factor H; D006493:Heparin