Injectable Artificial Photoreceptors: STEM Cell Functional Integration and in vivo Electrophysiological Validation in...

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Ophthalmology

Background:

• Vision loss due to retinal degeneration affects millions globally.
• Current treatments for retinal degeneration are limited, necessitating novel therapeutic approaches.
• Artificial photoreceptors offer a promising strategy for vision restoration.

Purpose of the Study:

• To engineer and evaluate an injectable artificial photoreceptor (APR) for vision restoration.
• To investigate the mechanism of light transduction and cellular response to APRs.
• To assess the in vivo efficacy of APRs in a preclinical model of retinal degeneration.

Main Methods:

• Fabrication of APRs using gold nanoparticles (AuNPs) coated with PVDF-HFP on a barium titanate core.
• In vitro evaluation using human pluripotent stem cell-derived retinal ganglion cells (hRGCs) and multielectrode arrays (MEAs).
• In vivo assessment in the rd1 mouse model via intravitreal injection, followed by VEP and PLR testing.

Main Results:

• APRs exhibited maximum absorbance at 525 nm and transduced visible light into electrical stimulation.
• In vitro studies showed increased hRGC firing and a shift towards oxidative phosphorylation without apoptosis.
• In rd1 mice, APRs restored light-evoked retinal activity, improved PLR, and enhanced VEP responses.

Conclusions:

• Injectable nanophotonic prostheses can restore light responsiveness in retinal degeneration models.
• APRs offer a potential electronic-free and gene-free approach to vision restoration.
• This technology holds promise for treating various forms of vision loss.