Wright, W. | Search bioRxiv

bioRxiv2019

Nano-enhanced optical gene delivery to retinal degenerated mice

The efficient and targeted delivery of genes and other impermeable therapeutic molecules into retinal cells is of immense importance for therapy of various visual disorders. Traditional methods for gene delivery require viral transfection, or chemical methods that suffer from one or many drawbacks such as invasiveness, low efficiency, lack of spatially targeted delivery, and can generally have deleterious effects such as unexpected inflammatory responses and immunological reactions. Here, we introduce a continuous wave near-infrared laser-based Nano-enhanced Optical Delivery (NOD) method for spatially controlled delivery of opsin-encoding genes into retina in-vivo. In this method, the optical field enhancement by gold nanorods is utilized to transiently permeabilize cell membrane enabling delivery of exogenous impermeable molecules to nanorod-binding cells in laser-irradiated regions. The successful delivery and expression of opsin in targeted retina after in-vivo NOD in the mice models of retinal degeneration opens new vista for re-photosensitizing retina with geographic atrophies as in dry age-related macular degeneration (AMD).

bioengineering↗

bioRxiv2018

Bioluminescent Multi-Characteristic Opsin for monitoring visual cortical activity upon optical stimulation

Non-invasive detection of neural activity is important for the diagnosis of neurological diseases, evaluation of therapeutic outcomes, and collection of real-time feedback for stimulation based therapeutic approaches. In the case of vision loss, due to retinal degeneration, optic neuropathy, or enucleation of the eye, there is a need to map changes in visual cortical activity during disease progression and subsequent vision restoration by retinal, optic nerve or cortical stimulation. Existing technologies allow interrogation of neuronal circuits by both read and write activity, albeit with inherent limitations. Here, we present the development of bioluminescent multi-characteristic opsin (bMCO-11), which is comprised of a highly photosensitive ambient light-activatable domain and a Ca2+-sensitive bioluminescence reporter. The high quantum efficiency of bMCO-11 enables light activation and recording of cellular activity upon local as well as wide area optical stimulation. Furthermore, persistent Ca2+ influx was achieved by bioluminescence based cyclic activation of the opsin-domain of bMCO-11 by transporting the ions only into bMCO expressing cells. This allowed us to continuously monitor visual cortical activity in wild type and retinal degenerated mice, without requiring any additional external excitation source.

neuroscience↗