Near-infrared dual bioluminescence imaging in mouse models of cancer using infraluciferin
- University College London, United Kingdom
- Institute of Cancer Research, United Kingdom
- Connecticut College, United States
Abstract
Bioluminescence imaging (BLI) is ubiquitous in scientific research for the sensitive tracking of biological processes in small animal models. However, due to the attenuation of visible light by tissue, and the limited set of near-infrared bioluminescent enzymes, BLI is largely restricted to monitoring single processes in vivo. Here we show, that by combining stabilised colour mutants of firefly luciferase (FLuc) with the luciferin (LH2) analogue infraluciferin (iLH2), near-infrared dual BLI can be achievedin vivo. The X-ray crystal structure of FLuc with a high-energy intermediate analogue, 5'-O-[N-(dehydroinfraluciferyl)sulfamoyl] adenosine (iDLSA) provides insight into the FLuc-iLH2 reaction leading to near-infrared light emission. The spectral characterisation and unmixing validation studies reported here established that iLH2 is superior to LH2 for the spectral unmixing of bioluminescent signals in vivo; which led to this novel near-infrared dual BLI system being applied to monitor both tumour burden and CAR T cell therapy within a systemically induced mouse tumour model.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Raw image files are available on Dryad Digital repository, at doi:10.5061/dryad.3j9kd51cs.
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Data from: Near-infrared dual bioluminescence imaging in mouse models of cancer using infraluciferinDryad Digital Repository, doi:10.5061/dryad.3j9kd51cs.
Article and author information
Author details
Funding
National Science Foundation (MCB-1410390)
- Tara L Southworth
- Bruce R Branchini
Air Force Office of Scientific Research (FA9550-18-1-0017)
- Tara L Southworth
- Bruce R Branchini
Engineering and Physical Sciences Research Council (EP/L504889/1)
- Helen Allan
- James C Anderson
University College London
- Helen Allan
- James C Anderson
Biotechnology and Biological Sciences Research Council
- Cassandra L Stowe
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal procedures were conducted in accordance with the Home Office Scientific Procedures Act (1986), within the guidelines of the relevant personal and project licences.
Copyright
© 2019, Stowe et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Near-infrared dual bioluminescence imaging in mouse models of cancer using infraluciferin
eLife 8:e45801.
https://doi.org/10.7554/eLife.45801
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