Long-Duration and Non-Invasive Photoacoustic Imaging of Multiple Anatomical Structures in a Live Mouse Using a Single...

Area of Science:

• Biomedical Imaging
• Preclinical Research
• Molecular Imaging

Background:

• Simultaneous in vivo imaging of multiple anatomical structures is crucial for disease understanding and preclinical research.
• Existing methods often rely on genetically engineered mice, which are costly and time-consuming.
• There is a need for efficient and accessible techniques for multi-structure imaging.

Purpose of the Study:

• To develop a novel, non-genetic method for simultaneous in vivo imaging of diverse anatomical structures.
• To evaluate the efficacy of a near-infrared dye-labeled antibody as a contrast agent for photoacoustic microscopy and tomography.
• To demonstrate the potential of this technique for improving preclinical therapeutic optimization and clinical outcomes.

Main Methods:

• An IgG4 isotype control antibody was labeled with a near-infrared dye.
• The labeled antibody was injected into mouse ears for simultaneous visualization of blood and lymphatic vessels, peripheral nerves, and sebaceous glands.
• Photoacoustic microscopy and photoacoustic computed tomography were employed for imaging up to 3 hours post-injection.

Main Results:

• Simultaneous visualization of blood and lymphatic vessels, peripheral nerves, and sebaceous glands was achieved for up to 3 hours.
• Peripheral nerves and sebaceous glands were imaged within the antibody mass, while lymphatic vessels were visualized outside it.
• The contrast agent effectively labeled and localized deep medial lymphatic vessels and lymph nodes.

Conclusions:

• A single injectable contrast agent enables long-duration, multi-structure in vivo imaging.
• This technique offers a cost-effective and time-efficient alternative to genetic methods.
• The approach has the potential to accelerate preclinical therapeutic development and enhance clinical treatments.