Activation of retinal ganglion cells using a biomimetic artificial retina

Abstract Objective. Biomimetic protein-based artificial retinas offer a new paradigm for restoring vision for patients blinded by retinal degeneration. Artificial retinas, comprised of an ion-permeable membrane and alternating layers of bacteriorhodopsin (BR) and a polycation binder, are assembled using layer-by-layer (LBL) electrostatic adsorption. Upon light absorption, the oriented BR layers generate a unidirectional proton gradient. The main objective of this investigation is to demonstrate the ability of the ion-mediated subretinal artificial retina to activate retinal ganglion cells (RGCs) of degenerated retinal tissue. Approach. Ex vivo extracellular recording experiments with P23H line 1 rats are used to measure the response of RGCs following selective stimulation of our artificial retina using a pulsed light source. Single-unit recording is used to evaluate the efficiency and latency of activation, while a multielectrode array (MEA) is used to assess the spatial sensitivity of the artificial retina films. Main results. The activation efficiency of the artificial retina increases with increased incident light intensity and demonstrates an activation latency of ~150 ms. The results suggest that the implant is most efficient with 200 BR layers and can stimulate the retina using light intensities comparable to indoor ambient light. Results from using an MEA show that activation is limited to the targeted receptive field. Significance. The results of this study establish potential effectiveness of using an ion-mediated artificial retina to restore vision for those with degenerative retinal diseases, including retinitis pigmentosa (RP).

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A method for single-neuron chronic recording from the retina in awake mice

Science ◽

10.1126/science.aas9160 ◽

2018 ◽

Vol 360 (6396) ◽

pp. 1447-1451 ◽

Cited By ~ 63

Author(s):

Guosong Hong ◽

Tian-Ming Fu ◽

Mu Qiao ◽

Robert D. Viveros ◽

Xiao Yang ◽

...

Keyword(s):

Retinal Ganglion Cells ◽

Visual Information ◽

Single Neuron ◽

Ganglion Cells ◽

Ex Vivo ◽

Neural Circuitry ◽

Retinal Ganglion ◽

Chronic Recording ◽

The Brain

The retina, which processes visual information and sends it to the brain, is an excellent model for studying neural circuitry. It has been probed extensively ex vivo but has been refractory to chronic in vivo electrophysiology. We report a nonsurgical method to achieve chronically stable in vivo recordings from single retinal ganglion cells (RGCs) in awake mice. We developed a noncoaxial intravitreal injection scheme in which injected mesh electronics unrolls inside the eye and conformally coats the highly curved retina without compromising normal eye functions. The method allows 16-channel recordings from multiple types of RGCs with stable responses to visual stimuli for at least 2 weeks, and reveals circadian rhythms in RGC responses over multiple day/night cycles.

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Imaging and Differentiation of Retinal Ganglion Cells in Ex Vivo Experimental Optic Nerve Degeneration by Differential Interference Contrast Microscopy

Current Eye Research ◽

10.1080/02713683.2019.1593463 ◽

2019 ◽

Vol 44 (7) ◽

pp. 760-769

Author(s):

Juyeong Oh ◽

Yu Jeong Kim ◽

Youngho Cho ◽

Subeen Park ◽

Hyung Min Kim ◽

...

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Ex Vivo ◽

Nerve Degeneration ◽

Differential Interference Contrast ◽

Retinal Ganglion ◽

Differential Interference Contrast Microscopy ◽

Contrast Microscopy ◽

Interference Contrast Microscopy ◽

Optic Nerve Degeneration

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Quantitative ex vivo detection of rodent retinal ganglion cells by immunolabeling Brn-3b

Experimental Eye Research ◽

10.1016/j.exer.2004.02.007 ◽

2004 ◽

Vol 79 (1) ◽

pp. 131-140 ◽

Cited By ~ 14

Author(s):

Kathleen M Leahy ◽

Richard L Ornberg ◽

Yu Wang ◽

Yanli Zhu ◽

Jeffrey M Gidday ◽

...

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Ex Vivo ◽

Retinal Ganglion

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The mito-QC Reporter for Quantitative Mitophagy Assessment in Primary Retinal Ganglion Cells and Experimental Glaucoma Models

International Journal of Molecular Sciences ◽

10.3390/ijms21051882 ◽

2020 ◽

Vol 21 (5) ◽

pp. 1882

Author(s):

Ines Rosignol ◽

Beatriz Villarejo-Zori ◽

Petra Teresak ◽

Elena Sierra-Filardi ◽

Xandra Pereiro ◽

...

Keyword(s):

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Ex Vivo ◽

Iron Chelator ◽

Stress Factors ◽

Retinal Ganglion ◽

Nerve Crush ◽

Experimental Glaucoma

Mitochondrial damage plays a prominent role in glaucoma. The only way cells can degrade whole mitochondria is via autophagy, in a process called mitophagy. Thus, studying mitophagy in the context of glaucoma is essential to understand the disease. Up to date limited tools are available for analyzing mitophagy in vivo. We have taken advantage of the mito-QC reporter, a recently generated mouse model that allows an accurate mitophagy assessment to fill this gap. We used primary RGCs and retinal explants derived from mito-QC mice to quantify mitophagy activation in vitro and ex vivo. We also analyzed mitophagy in retinal ganglion cells (RGCs), in vivo, using different mitophagy inducers, as well as after optic nerve crush (ONC) in mice, a commonly used surgical procedure to model glaucoma. Using mito-QC reporter we quantified mitophagy induced by several known inducers in primary RGCs in vitro, ex vivo and in vivo. We also found that RGCs were rescued from some glaucoma relevant stress factors by incubation with the iron chelator deferiprone (DFP). Thus, the mito-QC reporter-based model is a valuable tool for accurately analyzing mitophagy in the context of glaucoma.

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Modeling Activity and Target-Dependent Developmental Cell Death of Mouse Retinal Ganglion Cells Ex Vivo

PLoS ONE ◽

10.1371/journal.pone.0031105 ◽

2012 ◽

Vol 7 (2) ◽

pp. e31105 ◽

Cited By ~ 6

Author(s):

Sylvie Voyatzis ◽

Aude Muzerelle ◽

Patricia Gaspar ◽

Xavier Nicol

Keyword(s):

Cell Death ◽

Retinal Ganglion Cells ◽

Ganglion Cells ◽

Ex Vivo ◽

Retinal Ganglion ◽

Developmental Cell Death

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Efficient Inference of Sensitivity to Electrical Stimulation from Intrinsic Electrical Properties of Primate Retinal Ganglion Cells

10.1101/2021.10.22.465478 ◽

2021 ◽

Author(s):

Sasi S Madugula ◽

Lauren E Grosberg ◽

Nishal P Shah ◽

Alexandra Kling ◽

Alex R Goglietino ◽

...

Keyword(s):

Electrical Stimulation ◽

Electrical Properties ◽

Retinal Ganglion Cells ◽

Large Scale ◽

Ganglion Cells ◽

Ex Vivo ◽

High Fidelity ◽

Retinal Ganglion ◽

Neural Implants ◽

Sensory Neural

High-fidelity sensory neural implants must be calibrated to precisely activate specific cells via extracellular stimulation. However, collecting and analyzing the required electrical stimulation data may be difficult in the clinic. A potential solution is to infer stimulation sensitivity from intrinsic electrical properties. Here, this inference was tested using large-scale high-density stimulation and recording from macaque retinal ganglion cells ex vivo. Electrodes recording larger spikes exhibited lower activation thresholds, with distinct trends for somas and axons, and consistent trends across cells and retinas. Thresholds for somatic electrodes increased with distance from the axon initial segment. Responses were inversely related to thresholds, and exhibited a steeper dependence on injected current for axonal than somatic electrodes. Dendritic electrodes were largely ineffective for eliciting spikes. Biophysical simulations qualitatively reproduced these findings. Inference of stimulation sensitivity was employed in simulated visual reconstruction, revealing that the approach could improve the function of future high-fidelity retinal implants.

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A facile and comprehensive algorithm for electrical response identification in mouse retinal ganglion cells

PLoS ONE ◽

10.1371/journal.pone.0246547 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0246547

Author(s):

Wanying Li ◽

Shan Qin ◽

Yijie Lu ◽

Hao Wang ◽

Zhen Xu ◽

...

Keyword(s):

Electrical Stimulation ◽

Retinal Ganglion Cells ◽

Microelectrode Array ◽

Ganglion Cells ◽

Ex Vivo ◽

Electrical Response ◽

Pulse Amplitude ◽

Retinal Ganglion ◽

Pulse Parameters ◽

High Consistency

Retinal prostheses can restore the basic visual function of patients with retinal degeneration, which relies on effective electrical stimulation to evoke the physiological activities of retinal ganglion cells (RGCs). Current electrical stimulation strategies have defects such as unstable effects and insufficient stimulation positions, therefore, it is crucial to determine the optimal pulse parameters for precise and safe electrical stimulation. Biphasic voltages (cathode-first) with a pulse width of 25 ms and different amplitudes were used to ex vivo stimulate RGCs of three wild-type (WT) mice using a commercial microelectrode array (MEA) recording system. An algorithm is developed to automatically realize both spike-sorting and electrical response identification for the spike signals recorded. Measured from three WT mouse retinas, the total numbers of RGC units and responsive RGC units were 1193 and 151, respectively. In addition, the optimal pulse amplitude range for electrical stimulation was determined to be 0.43 V-1.3 V. The processing results of the automatic algorithm we proposed shows high consistency with those using traditional manual processing. We anticipate the new algorithm can not only speed up the elaborate electrophysiological data processing, but also optimize pulse parameters for the electrical stimulation strategy of neural prostheses.

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Electrophysiological Approaches to Studying Normal and Abnormal Retinotectal Circuit Development in the Xenopus Tadpole

Cold Spring Harbor Protocols ◽

10.1101/pdb.prot106898 ◽

2021 ◽

Vol 2021 (11) ◽

pp. pdb.prot106898 ◽

Cited By ~ 1

Author(s):

Kara G. Pratt

Keyword(s):

Retinal Ganglion Cells ◽

Neural Circuits ◽

Ganglion Cells ◽

Ex Vivo ◽

Retinal Ganglion ◽

Functional Development ◽

Electrophysiological Recordings ◽

Circuit Development ◽

Tectal Neurons ◽

Main Component

The Xenopus tadpole retinotectal projection is the main component of the amphibian visual system. It comprises the retinal ganglion cells (RGCs) in the eye, which project an axon to synapse onto tectal neurons in the optic tectum. There are many attributes of this relatively simple projection that render it uniquely well-suited for studying the functional development of neural circuits. One major experimental advantage of this circuit is that it can be genetically or pharmacologically altered and then assessed at high resolution via whole-cell electrophysiological recordings using an ex vivo isolated brain preparation. This protocol provides instructions for performing such electrophysiological investigations using the ex-vivo-isolated brain preparation. It allows one to measure many different aspects of synaptic transmission between the RGC axons and individual postsynaptic tectal neurons, including AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) to NMDA (N-methyl-d-aspartate) ratios, strength of individual RGC axons, paired pulse facilitation, and strength of individual synapses.

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