Mechanism of interaction between tissue factor pethway inhibitor and heparin

利用一系列肝素衍生物作为配体，通过化学方法进行区域选择性脱硫，开发了表面等离子体共振来分析肝素与蛋白质的相互作用，特别是为了评估肝素的每个硫酸基团的作用。为了获得精确测量所需的高响应，优化了在表面等离子体共振装置的小皿上固定肝素的方法。以糖壳聚糖为多价连接剂，将肝素还原端引入的氨基与小瓶表面的羧甲基葡聚糖偶联，效果最好。所建立的系统似乎很好地描述了肝素与酸性和碱性成纤维细胞生长因子和组织因子途径抑制剂等蛋白质的相互作用。采用表面等离子体共振和区域选择性肝素相结合的方法，揭示了肝素硫酸基团在与肝素相互作用中的作用。结果表明，2-O、2-N和6-O这三个硫酸盐基团都参与了分子间的相互作用，其中6-O-硫酸盐基团的贡献最大。

Surface plasmon resonance was developed to analyze the heparin-protein interaction using as ligands a series of heparin derivatives regioselectively desulfated by chemical methods, particularly in order to evaluate the effect of each sulfate group of heparin. The method for immobilizing heparin on the cuvette of the surface plasmon resonance equipment was optimized in order to obtain the high response required for accurate measurement. The best result was achieved when the amino group introduced at the reducing end of heparin was coupled with carboxymethyl dextran on the surface of the cuvette using glycolchitosan as a multi-valent linker. The established system appeared to describe well the interactions of heparin with such proteins as acidic and basic fibroblast growth factors and tissue factor pathway inhibitor.Using the combination of surface plasmon resonance and regioselectively heparins, the role of sulfate groups of heparin in the interaction with heparin was revealed. The results obtained indicated that all sulfate groups, 2-O, 2-N, and 6-O, contribute in the interaction of both molecule, and the contribution of 6-O-sulfate group is the largest.