2017年第二届曲阜视觉科学会议知识库

PURPOSE: The restoration of light response with complex spatiotemporal features in retinal degenerative diseases towards retinal prosthesis has proven to be a considerable challenge over the past decades. The state-of-art retinal prosthesis utilizes photodiode arrays fabricated on solid substrates, which does not have a complete tiling of the retinal tissue. Polymer based optoelectronic interface to retinal tissue, despite being compatible with flexible substrates, has limited spatial resolution for vision. Herein, inspired by the structure and function of photoreceptors in retinas, we developed bio-inspired artificial photoreceptors, i.e. gold nanoparticle-decorated titania (Au-TiO2) nanowire arrays, for restoration of multi-color visual responses in the retina of blind mice with degenerated photoreceptors.
METHODS: single-cell intracellular measurements by patch-clamps, functional calcium imaging, in vivo electrophysiological recording, Pupillary light reflex.
RESULTS: When Au-TiO2 nanowire arrays were in direct contact with blind mice retina, single-cell intracellular measurements by patch-clamps in the retinal ganglion cells (RGCs) revealed that green, blue and UV light responses were restored with a spatial resolution approaching or exceeding 100 µm. Light responses in RGCs can be blocked by glutamatergic antagonists, indicating that nanowire array-interfaced retinas were capable of processing visual information through innate retinal circuits. Moreover, cellular-level population responses using functional calcium imaging in the Au-TiO2 nanowire array-interfaced blind retinas indicated that the receptive field is within the range of 200 µm. Neurons in the primary visual cortex responded to light in vivo after subretinal implant of the nanowire arrays into the blind mice. The blind mice had lost a part of ability of the pupillary light reflex. But after subretinal implant of NW array, the blind mice regained the ability of pupillary light reflex.
CONCLUSIONS: This study is among the first to show bio-inspired artificial photoreceptors and will shed light on the development of a new generation of optoelectronic toolkits for photo-coded subretinal implants and prosthetic devices.