Age-specific differences in binding of heparin to plasma proteins

Background: Clinically significant age-related differences in the anticoagulation effect of heparin have previously been established in vitro as well as in different clinical settings in vivo. These differences were hypothesized to be due to the age-specific differences in binding of heparin to plasma proteins. Objectives: The aim of this project was to investigate global age-related differences in heparin binding to plasma proteins. Patients/Methods: Heparin-binding proteins were identified by incubating heparin-coated magnetic beads with plasma samples from neonates, children and adults, and purifying the proteins that were bound to the beads in this reaction system. Results: These results provide the first preliminary evidence of age-related differences in the total number and concentration of proteins bound to heparin. The results also suggest, for the first time, that there are age-related differences of heparin binding to antithrombin and thrombin. Conclusions: The results of this study, although preliminary, support and contribute to the explanation of the mechanism of age-related differences in the effect of heparin observed previously in vitro and in vivo.