Near infrared readouts offer sensitive and rapid assessments of intestinal permeability and disease severity in inflammatory bowel disease models

Liang Zhang,Rajesh V Kamath,Marc A Wurbel,Stephanie M Gaudette,Christine M Nelson,Samuel D Karsen,Soumya Mitra,Jamie E Erickson,Craig D Wallace,Bradford L Mcrae,Annette J Schwartz Sterman,Calvin S Pohl,F Stephen Laroux,Christopher A Stedman,Ruoqi Peng,Gricelda H Simler

doi:10.1038/s41598-020-61756-y

Liang Zhang, Rajesh V Kamath + Show 14 more

Open Access

https://doi.org/10.1038/s41598-020-61756-y

Copy DOI

Journal: Scientific Reports	Publication Date: Mar 13, 2020
Citations: 6	License type: open-access

Affiliation: AbbVie (United States)

Abstract

Intestinal permeability and neutrophil activity are closely linked to inflammatory bowel disease (IBD) pathophysiology. Here we discuss two techniques for assessing permeability and neutrophil activity in mouse IBD models using near infrared (NIR) detection. To address the limitation of visible light readouts—namely high background—IRDye 800CW was used to enable rapid, non-terminal measurements of intestinal permeability. The increased sensitivity of NIR readouts for colon permeability is shown using dextran sulfate sodium (DSS) and anti-CD40 murine colitis models in response to interleukin-22 immunoglobulin Fc (IL22Fc) fusion protein and anti-p40 monoclonal antibody treatments, respectively. In addition to enhanced permeability, elevated levels of neutrophil elastase (NE) have been reported in inflamed colonic mucosal tissue. Activatable NIR fluorescent probes have been extensively used for disease activity evaluation in oncologic animal models, and we demonstrate their translatability using a NE-activatable reagent to evaluate inflammation in DSS mice. Confocal laser endomicroscopy (CLE) and tissue imaging allow visualization of spatial NE activity throughout diseased colon as well as changes in disease severity from IL22Fc treatment. Our findings with the 800CW dye and the NE probe highlight the ease of their implementation in preclinical IBD research.

Highlights

Intestinal permeability and neutrophil activity are closely linked to inflammatory bowel disease (IBD) pathophysiology
The optical properties of near infrared (NIR) and far red fluorophores allow for improved sensitivity for colon permeability and neutrophil elastase (NE) activity imaging. 800CW carboxylate and fluorogenic NE680 were orally and intravenously administered, respectively. 800CW is absorbed from the colon to blood, where it can be quantified via blood sampling
We hypothesized that a successful NIR permeability marker will be stable in the stomach, have adequate colon bioavailability for detection, exhibit blood stability, and clear rapidly through renal filtration

Summary

Introduction

Intestinal permeability and neutrophil activity are closely linked to inflammatory bowel disease (IBD) pathophysiology. Chemical damage to the colonic epithelial layer allows bacteria and other proinflammatory contents to reach underlying tissue Using this model, we evaluate 800CW permeability and NE680 disease activity imaging in response to treatment with an IL22Fc fusion protein promoting epithelial repair[27]. We evaluate 800CW permeability and NE680 disease activity imaging in response to treatment with an IL22Fc fusion protein promoting epithelial repair[27] To our knowledge, this is the first use of a NE sensitive marker to detect and quantify inflammation in a rodent colitis model. Wurbel et al demonstrated a dose-dependent model of anti-CD40 colitis in wild-type immunocompetent mice[30] In this acute anti-CD40 model, where inflammation but no epithelial erosion is observed via histopathology, FITC-dextran is unable to measure changes in colon permeability. We hypothesize that these small changes in permeability accompanying the acute response will be detectable via 800CW, and selected this model to demonstrate the increased sensitivity of NIR detection

Methods

Results

Conclusion