Injections of AAV Vectors for Optogenetics in Anesthetized and Awake Behaving Non-Human Primate Brain

Area of Science:

• Neuroscience
• Gene Therapy
• Medical Devices

Background:

• Optogenetics offers revolutionary potential for neuroscience and neurological gene therapy.
• Clinical translation requires rigorous safety and efficacy testing in non-human primates (NHPs) due to their brain similarity to humans.
• Current limitations exist in high-throughput testing of viral vectors for NHP brain applications.

Purpose of the Study:

• To develop a method for accurate, high-throughput, spatially defined viral vector injections in the NHP brain.
• To enable unambiguous identification of injected vectors via postmortem histology.
• To facilitate the preclinical evaluation of viral vectors for optogenetic applications.

Main Methods:

• Utilized custom-designed injection cannulas made from polytetrafluoroethylene and stainless steel.
• Incorporated a red-dyed mineral oil to fill dead space, enabling precise measurement of injection volume and rate.
• Developed a procedure for rapid cannula loading (10 min) and injection (20 min) suitable for awake or anesthetized animals.

Main Results:

• The method allows for multiple, spatially accurate viral vector injections in the NHP brain.
• The mineral oil tracer provides instantaneous and accurate volume and rate measurements.
• Demonstrated robust expression of optogenetic proteins following viral vector delivery.

Conclusions:

• This novel injection technique addresses the need for high-throughput preclinical testing of viral vectors in NHPs.
• The method supports the advancement of optogenetic tools for neurological gene therapy.
• Enables optical control of neural activity and behavior in NHPs, paving the way for clinical applications.