title: Detection of surface bound complement at increasing serum anticoagulant concentrations.
abstract: Surface mediated immune complement activation can be detected by a variety of antibody utilizing methods such as ELISA, fluorescence- or radiolabelling techniques, QCM, and ellipsometry. In the present work we investigated how the common anticoagulants heparin, dalteparin, fondaparinux and sodium citrate affected the binding of anti-complement factor 3c (anti-C3c) on a model complement activator surface, immobilised IgG, after incubation in human blood serum. The results show, as expected, that different anticoagulants affect the antibody binding differently. Increasing amounts of heparin, dalteparin and sodium citrate in normal serum resulted in a decreasing anti-C3c binding. The antibody deposition was not sensitive for the fondaparinux concentration. Surprisingly high concentrations of anti-coagulantia were needed to completely eradicate the antibody binding. Experiments in EGTA-serum showed that anticoagulants interfered directly with both the classical and alternative pathways. Control C3a-des arg ELISA measurements show that the lowered antibody surface binding was not a result of complement depletion in serum. Kallikrein generation by hydrophilic glass surfaces was not affected by high anticoagulant concentrations.
authors.affiliation: Division of Applied Physics, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Arvidsson
authors.forename: A
authors.initials: A
authors.lastname: Askendal
authors.forename: T L
authors.initials: TL
authors.lastname: Lindahl
authors.forename: P
authors.initials: P
authors.lastname: Tengvall
mesh_terms: D000925:Anticoagulants / Q000097:blood* / Q000494:pharmacology*; D001798:Blood Proteins / Q000378:metabolism; D003124:Colorimetry; D003167:Complement Activation / Q000187:drug effects*; D003176:Complement C3 / Q000378:metabolism; D015926:Complement C3a / Q000378:metabolism; D003165:Complement System Proteins / Q000032:analysis*; D017985:Dalteparin / Q000494:pharmacology; D004533:Egtazic Acid; D004797:Enzyme-Linked Immunosorbent Assay; D000077425:Fondaparinux; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D007118:Immunoassay; D007074:Immunoglobulin G / Q000737:chemistry; D066298:In Vitro Techniques; D007202:Indicators and Reagents; D007610:Kallikreins; D008970:Molecular Weight; D011134:Polysaccharides / Q000494:pharmacology; D020349:Surface Plasmon Resonance; D013499:Surface Properties
chemical_list: D000925:Anticoagulants; D001798:Blood Proteins; D003176:Complement C3; D007074:Immunoglobulin G; D007202:Indicators and Reagents; D011134:Polysaccharides; D004533:Egtazic Acid; D015926:Complement C3a; D006493:Heparin; D003165:Complement System Proteins; D007610:Kallikreins; D000077425:Fondaparinux; D017985:Dalteparin