Abstract 2149: Real Time Imaging of Targeted Microbubbles to Human Endothelium.
Ultrasound contrast agents (CA) are encapsulated microbubbles (μB) with a biocompatible shell that allows binding monoclonal antibodies for specific targeting. The aim of this study was to assess, using real time ultrasonography (US), the binding of targeted μB to human endothelium of umbilical cord vein in an ex vivo model.
Methods: Umbilical cord segments of 6 to 8 cm were employed. Canulated veins, washed with an heparinated solution and immersed in a saline bath at 30–36°C were infused with 10 ml of antiCD9-carrying biotinylated μB solution (13106 μB/ml; μB mean diameter: 3μm) at 1.6 ml/min (calculated mean velocity: 0.7 mm/s, similar to capillary flow rate). A 1.7–3.4 MHz US transducer was coupled with a fixed arm for real-time recording, using contrast imaging settings (focus depth: 5 cm, 43 Hz, mechanical index: 0.11).
Results: real time images of the μB adhesion on endothelial surface of the vein were obtained (figure⇓). In conclusion, real time imaging using targeted microbubbles is feasible in human ex vivo models. The high spatial-temporal resolution, portability, low-cost and the wide availability, made this technique a powerful molecular imaging tool.