# Dual orthogonal fluorescent protease sensors for image guided surgery

> **NIH NIH R01** · STANFORD UNIVERSITY · 2020 · $377,028

## Abstract

Project Summary
While there are an increasing number of useful chemotherapy and radiological methods available for cancer
therapy, the predominant treatment strategy remains surgical resection of the tumor. The greatest challenges
for the surgeon are 1) precisely and rapidly locating the primary lesion and 2) clearly defining the margins
between tumor and normal tissues. Failure in the form of recurrence after surgery usually results from
incomplete removal of all cancer cells. There have been a number of recent advances in the use of optical
contrast agents for fluorescence imaging guided surgery (FIGS). However, the only FDA approved optical
agents are non-targeted dyes that are mainly used for perfusion imaging and in some cases have increased
uptake in tumor tissues. A number of molecularly targeted optical contrast agents have recently advanced to
clinical trials. In addition, there are a number of optical probes that exploit the activity of enzymes such as
proteases that are activated in the tumor microenvironment. We have developed optical ‘smart probes’ that
produce a signal only when acted upon by a class of proteases found in activated macrophages within the
tumor microenvironment. While these probes have already been proven to be valuable agents for real time
tumor imaging during surgery using the FDA approved da Vinci surgical system, they still suffer from relatively
high background in some tissues and limited dynamic range of signal that depends on local probe
concentrations. To address these limitations, we outline the design of a paradigm-shifting class of optical
probes that require multiple tumor-specific enzyme signatures for activation, as well as a FRET imaging
strategy to enhance both sensitivity and selectivity of probes. We will couple these probes with camera and
image processing systems that will further enable their eventual clinical translation. This proposal is built
around a large body of preliminary data resulting from an active collaboration between the Bogyo Lab and
Intuitive Surgical Inc. These initial results have validated the key concept of using protease probes to image
tumor margins during surgery using existing FDA approved surgical systems and serve as a strong foundation
for the proposed studies aimed at enhancing the utility of existing optical imaging probes in the surgical
workflow.

## Key facts

- **NIH application ID:** 10018651
- **Project number:** 5R01EB028628-02
- **Recipient organization:** STANFORD UNIVERSITY
- **Principal Investigator:** Matthew Bogyo
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $377,028
- **Award type:** 5
- **Project period:** 2019-09-14 → 2023-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10018651

## Citation

> US National Institutes of Health, RePORTER application 10018651, Dual orthogonal fluorescent protease sensors for image guided surgery (5R01EB028628-02). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10018651. Licensed CC0.

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