The effect of surface contact activation and temperature on plasma coagulation with an RNA aptamer directed against factor IXa

The anticoagulant properties of a novel RNA aptamer that binds FIXa depend collectively on the intensity of surface contact activation of human blood plasma, aptamer concentration, and its binding affinity for FIXa. Accordingly, anticoagulation efficiency of plasma containing any particular aptamer concentration is low when coagulation is strongly activated by hydrophilic surfaces compared to the anticoagulation efficiency in plasma that is weakly activated by hydrophobic surfaces. Anticoagulation efficiency is lower at hypothermic temperatures possibly because aptamer-FIXa binding decreases with decreasing temperatures. Experimental results demonstrating these trends are qualitatively interpreted in the context of a previously established model of anticoagulation efficiency of thrombin-binding DNA aptamers that exhibit anticoagulation properties similar to the FIXa aptamer. In principle, FIXa aptamer anticoagulants should be more efficient and therefore more clinically useful than thrombin-binding aptamers because aptamer binding to FIXa competes only with FX that is at much lower blood concentration than fibrinogen (FI) that competes with thrombin-binding aptamers. Our findings may have translatable relevance in the application of aptamer anticoagulants for clinical conditions in which blood is in direct contact with non-biological surfaces such as those encountered in cardiopulmonary bypass circuits.

[1]  B. A. Brown Hematology: Principles and Procedures , 1973 .

[2]  D. Hughes,et al.  Late complications of undetected urethral stricture after cardiac surgery in a child. , 1991, BMJ.

[3]  W. Brittain,et al.  Contact activation of the plasma coagulation cascade. II. Protein adsorption to procoagulant surfaces. , 1995, Journal of biomedical materials research.

[4]  W J Brittain,et al.  Contact activation of the plasma coagulation cascade. I. Procoagulant surface chemistry and energy. , 1995, Journal of biomedical materials research.

[5]  J. Cooper,et al.  Activation of factors XII and VII induced in citrated plasma in the presence of contact surface. , 1995, Thrombosis research.

[6]  E. Vogler,et al.  Contact activation of the plasma coagulation cascade. III. Biophysical aspects of thrombin-binding anticoagulants. , 1998, Journal of biomedical materials research.

[7]  K. Mitropoulos The Levels of Factor XIIa Generated in Human Plasma on an Electronegative Surface Are Insensitive to Wide Variation in the Concentration of FXII, Prekallikrein, High Molecular Weight Kininogen or FXI , 1999, Thrombosis and Haemostasis.

[8]  B. Sullenger,et al.  Blocking the Initiation of Coagulation by RNA Aptamers to Factor VIIa , 2000, Thrombosis and Haemostasis.

[9]  M. Morra Water in biomaterials surface science , 2001 .

[10]  B. Sullenger,et al.  RNA aptamers as reversible antagonists of coagulation factor IXa , 2002, Nature.

[11]  N. Anderson,et al.  The Human Plasma Proteome , 2002, Molecular & Cellular Proteomics.

[12]  Therapeutic aptamers and antidotes: a novel approach to safer drug design. , 2003, Ernst Schering Research Foundation workshop.

[13]  George Quick,et al.  Antidote-mediated control of an anticoagulant aptamer in vivo , 2004, Nature Biotechnology.

[14]  R. Becker Novel constructs for thrombin inhibition. , 2005, American heart journal.

[15]  R. Becker Cell-Based Models of Coagulation: A Paradigm in Evolution , 2005, Journal of Thrombosis and Thrombolysis.

[16]  B. Sullenger,et al.  Aptamers: an emerging class of therapeutics. , 2005, Annual review of medicine.

[17]  E. Vogler,et al.  Procoagulant stimulus processing by the intrinsic pathway of blood plasma coagulation. , 2005, Biomaterials.

[18]  E. Vogler,et al.  Silicon oxycarbide glasses for blood-contact applications. , 2005, Acta biomaterialia.

[19]  B. Sullenger,et al.  The potential of aptamers as anticoagulants. , 2005, Trends in cardiovascular medicine.

[20]  B. Sullenger,et al.  A novel antidote-controlled anticoagulant reduces thrombin generation and inflammation and improves cardiac function in cardiopulmonary bypass surgery. , 2006, Molecular therapy : the journal of the American Society of Gene Therapy.

[21]  R. Becker,et al.  Factor IXa inhibitors as novel anticoagulants. , 2007, Arteriosclerosis, thrombosis, and vascular biology.

[22]  Nucleic acid aptamers and their complimentary antidotes. Entering an era of antithrombotic pharmacobiologic therapy. , 2007, Hamostaseologie.

[23]  R. Becker Emerging paradigms, platforms, and unifying themes in biomarker science. , 2007, Journal of the American College of Cardiology.

[24]  R. Becker,et al.  Coagulation and fibrinolytic protein kinetics in cardiopulmonary bypass , 2007, Journal of Thrombosis and Thrombolysis.

[25]  Jijun Tang,et al.  High‐sensitive determination of human α‐thrombin by its 29‐mer aptamer in affinity probe capillary electrophoresis , 2008, Electrophoresis.

[26]  R. Becker,et al.  Anticoagulant therapy during cardiopulmonary bypass , 2008, Journal of Thrombosis and Thrombolysis.

[27]  E. Vogler,et al.  Contact activation of blood-plasma coagulation. , 2009, Biomaterials.

[28]  B. Sullenger,et al.  Translating Nucleic Acid Aptamers to Antithrombotic Drugs in Cardiovascular Medicine , 2010, Journal of cardiovascular translational research.

[29]  E. Vogler,et al.  Surface-energy dependent contact activation of blood factor XII. , 2010, Biomaterials.

[30]  R. Becker,et al.  Dose Selection for a Direct and Selective Factor IXa Inhibitor and its Complementary Reversal Agent: Translating Pharmacokinetic and Pharmacodynamic Properties of the REG1 System to Clinical Trial Design , 2011, Journal of Thrombosis and Thrombolysis.