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bioRxiv · 10.1101/2024.01.15.575593

ARViS: A bleed-free multi-site automated injection robot for accurate, fast, and dense delivery of virus to mouse and marmoset brains

Nomura, S.·Terada, S.-I.·Ebina, T.·Uemura, M.·Masamizu, Y.·Ohki, K.·Matsuzaki, M.
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Abstract

Genetically encoded fluorescent sensors continue to be developed and improved. If they could be expressed across multiple cortical areas in non-human primates, it would be possible to measure a variety of spatiotemporal dynamics of primate-specific cortical activity. Here, we develop an Automated Robotic Virus injection System (ARViS) for broad expression of a biosensor. ARViS consists of two technologies: image recognition of vasculature structures on the cortical surface to determine multiple injection sites without hitting them, and robotic control of micropipette insertion perpendicular to the cortical surface with 50-m precision. In mouse cortex, ARViS sequentially injected virus solution into 100 sites over a duration of 100-minutes with a bleeding probability of only 0.1% per site. Furthermore, ARViS successfully achieved 266-site injections over the frontoparietal cortex of a common marmoset. We demonstrate one-photon and two-photon calcium imaging in the marmoset frontoparietal cortex, illustrating the effective expression of biosensors delivered by ARViS.

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Nomura, S., Terada, S.-I., Ebina, T., Uemura, M., Masamizu, Y., Ohki, K., Matsuzaki, M.. 2024-01-15. ARViS: A bleed-free multi-site automated injection robot for accurate, fast, and dense delivery of virus to mouse and marmoset brains. https://doi.org/10.1101/2024.01.15.575593

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