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bioRxiv · 10.1101/2021.08.17.456633

Guided Axon Outgrowth of Neurons by Real-Time Femtosecond Laser Penetration on a 4 μm Thick Thin-Glass Sheet

Anggraini, D.·Liu, X.·Okano, K.·Tanaka, Y.·Inagaki, N.·Li, M.·Hosokawa, Y.·Yamada, S.·Yalikun, Y.
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Abstract

Transplantation of scaffold-embedded guided neurons has been reported to increase neuronal regeneration following brain injury. However, precise axonal integration between host and transplant neurons to form functional synapses remains a major problem. This study aims to develop a real-time femtosecond (fs) laser penetration on a 4 m thick thin-glass sheet to promote guided axon outgrowth influenced by molecular gradients in a microfluidic device. The device enables the introduction of the guidance molecule (i.e., netrin-1), neuronal culture, and manipulation by fs laser. After fabricating multiple micro-holes on the thin-glass sheet using fs laser, netrin-1 gradients with radial concentrations are generated in the chamber, affecting axon outgrowth and guidance. A majority of axons (~92%) experiences guided outgrowth with positive angular changes towards netrin-1 gradients. These results demonstrate the capability of the precise and real-time manipulation system based on a fs laser and a microfluidic device to control the growth of neurons.

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Anggraini, D., Liu, X., Okano, K., Tanaka, Y., Inagaki, N., Li, M., Hosokawa, Y., Yamada, S., Yalikun, Y.. 2021-08-19. Guided Axon Outgrowth of Neurons by Real-Time Femtosecond Laser Penetration on a 4 μm Thick Thin-Glass Sheet. https://doi.org/10.1101/2021.08.17.456633

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