Functionalized polymer microbubbles as new molecular ultrasound contrast agent to target P-selectin in thrombus
Bo Li, Rachida Aid-Launais, Marie-Noëlle Labour, Alina Zenych, Maya Juenet, Christine Choqueux, Véronique Ollivier, Olivier Couture, Didier Letourneur, Cédric ChauvierreBiomaterials2019
Thrombotic diseases rarely cause symptoms until advanced stage and sudden death. Thus, early detection of thrombus by a widely spread imaging modality can improve the prognosis and reduce mortality. Here, polymer microbubbles (MBs) made of degradable poly(IsoButylCyanoAcrylate) and functionalized with fucoidan (Fucoidan-MBs) were designed as a new targeted ultrasound contrast agent to image venous thrombus. The physicochemical characterizations demonstrate that the MBs with fucoidan surface exhibit a size of 2–6 μm and stability in suspension at 4 °C up to 2 months. MBs exhibit high echogenicity and could be completely burst under high destructive pulse. Flow chamber experiments on activated human platelets show a higher affinity of Fucoidan-MBs than control anionic MBs (CM-Dextran-MBs) under shear stress conditions. In vivo analysis by ultrasound and histological results demonstrate that Fucoidan-MBs are localized in rat venous thrombotic wall, whereas few CM-Dextran-MBs are present. In addition, the binding of Fucoidan-MBs in healthy vein is not observed. Collectively, Fucoidan-MBs appear as a promising functionalized carrier for ultrasound molecular imaging in thrombotic diseases.