Development and characterization of a recombinant hybrid protein with anticoagulant and antiplatelet activities

• Grant number: 25/04421-8
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2025
• End date: October 31, 2028
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Geraldo Santana Magalhães
• Grantee: Geraldo Santana Magalhães
• Host Institution: Instituto Butantan. São Paulo , SP, Brazil
• City of the host institution: São Paulo
• Associated researchers: Eliana Faquim de Lima Mauro

Abstract

Arterial and venous thrombosis represents one of the major challenges in cardiovascular medicine, contributing significantly to global morbidity and mortality rates. Currently, the primary therapeutic approach involves anticoagulant and antiplatelet combinations, which, despite their effectiveness, carry increased risks of bleeding complications. In this context, molecules derived from natural sources that can selectively modulate hemostasis, such as factor Xa inhibitors from insect saliva and snake venom disintegrins, have emerged as promising candidates. This project aims to develop and characterize a recombinant hybrid protein combining a factor Xa inhibitor isolated from the salivary gland of the insect Simulium pertinax with Echistatin, a potent disintegrin from the snake Echis carinatus. This hybrid molecule, named SpKunEch, aims to integrate factor Xa inhibition with platelet aggregation blockage in a single protein, thereby reducing the need for drug coadministration and minimizing hemorrhagic complications. To validate its biological function, SpKunEch will be cloned, expressed in Escherichia coli, purified, and structurally characterized using mass spectrometry. Its effectiveness will then be evaluated in vivo through bleeding time assays in mice, along with hemostatic assessments using rotational thromboelastometry (ROTEM). Furthermore, neutralizing monoclonal antibodies will be generated to allow selective reversal of SpKunEch's activity when necessary, providing an additional safety measure. If successful, this study could yield a novel recombinant protein with significant clinical potential, supporting safer therapeutic strategies in cardiovascular medicine and advancing recombinant protein engineering applications, with strong translational and patenting prospects. (AU)