# Optimization of a Minimally-Invasive Bidirectional Optogenetic Peripheral Nerve Interface with Single Axon Read-in & Read-out Specificity

> **NIH NIH R01** · UNIVERSITY OF COLORADO DENVER · 2020 · $624,492

## Abstract

Project Abstract
 We propose to develop a chronically implantable, all optical, optogenetic nerve interface that can non-
invasively, optically neuromodulate individual axons of nerves in the parasympathetic or peripheral nervous
system. The proposed interface would benefit treatment of human disease and disabilities related to the
thoracic and abdominal organs and systems innervated by the cervical vagus nerve, such as epilepsy and
metabolic disorders. We propose to optically interface from afferent/efferent axons in these nerves with the
goal of modulating organs or brain circuits innervated by them. The bidirectional optical neural interface
technology will utilize the capabilities of optogenetics enabled through viral vector transfection of afferent
and/or efferent neurons with genetically targeted, optically activated reporter proteins and opsins.
 Our central premise is that we can use optics to communicate with axons in a nerve. For optical
approaches to work we need to convert action potentials into an optical signal. This can be done using
genetically encoded calcium indicators or other voltage sensitive proteins that change their fluorescent
properties upon action potential generation in a neuron. Because nerves do not naturally express optical
proteins, we will work with transgenic mice that express these proteins and use these mice models to refine
our system before making it available for other researchers to use.
We aim to develop a compact, bench-top optical system that can be shared with other research labs to provide
the unique ability of being able to interrogate specific fascicles and axons within the nerve. In the future, this
technology has potential for translation to human clinical applications. The technology in the proposal is
ambitious, but we have formed an outstanding team of cell biologists, neuroscientists, biomedical, electrical,
and mechanical engineers. The team has an excellent track record of successful collaborations on multiple
grants and publications.

## Key facts

- **NIH application ID:** 10034743
- **Project number:** 1R01NS118188-01
- **Recipient organization:** UNIVERSITY OF COLORADO DENVER
- **Principal Investigator:** JOHN H CALDWELL
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $624,492
- **Award type:** 1
- **Project period:** 2020-09-30 → 2025-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10034743

## Citation

> US National Institutes of Health, RePORTER application 10034743, Optimization of a Minimally-Invasive Bidirectional Optogenetic Peripheral Nerve Interface with Single Axon Read-in & Read-out Specificity (1R01NS118188-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10034743. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*