A Minimally Invasive, Accurate, and Efficient Technique for Intrathymic Injection in Mice

Area of Science:

• Immunology
• Mouse Models
• Surgical Techniques

Background:

• Intrathymic injection is crucial for studying thymic and immune function in mouse models.
• Traditional methods like surgery or blind injections have significant limitations.
• Existing image-guided techniques often rely on rigid, time-consuming rail systems.

Purpose of the Study:

• To present a unique, safe, and efficient free-hand ultrasound-guided method for percutaneous intrathymic injections in mice.
• To eliminate the need for specialized rail systems in image-guided injections.
• To improve the precision and efficiency of reagent/cell delivery to the mouse thymus.

Main Methods:

• Utilized a high-resolution micro-ultrasound unit for noninvasive imaging of the mouse thymus.
• Employed a free-hand technique for needle placement under real-time sonographic guidance.
• Performed injections on anesthetized mice, with a short learning period for experienced radiologists.

Main Results:

• The novel technique allows precise, reliable percutaneous intrathymic injections without a rail system.
• Achieved a low morbidity and mortality rate in mice.
• Demonstrated a significantly faster procedure compared to mechanically assisted techniques, suitable for large-scale experiments and small thymuses.

Conclusions:

• This free-hand ultrasound-guided method provides a superior approach for intrathymic injections in mice.
• The technique is efficient, accurate, and minimally invasive, reducing animal stress.
• Facilitates research on thymic and immune function, T cell disorders, and enables targeted delivery to individual thymic lobes.