Free-hand ultrasound guidance permits safe and efficient minimallyinvasive intrathymic injections in both young and aged mice

摘要

The goal of this study was to evaluate whether using an aseptic free-hand approach for ultrasound-guided injection facilitates injection into the thymic gland in mice. We used this interventional radiology technique in young, aged, and immunodeficient mice and found that the thymus was visible in all cases. The mean injection period was 8 s in young mice and 19 s in aged or immunodeficient mice. Injection accuracy was confirmed by intrathymic location of an injected dye, or by in vivo bioluminescence imaging of injected luciferase-expressing cells. Accurate intrathymic injection was confirmed in 97% of cases. No major complications were observed. We conclude that an aseptic free-hand technique for ultrasound-guided intrathymic injection is safe, accurate, and reduces the time required for intrathymic injections. This method facilitates large-scale experiments, injection of individual thymic lobes, and is clinically relevant.