Generation of light-producing somatic-transgenic mice using adeno-associated virus vectors

Rajvinder Karda,Nuria Palomar Martin,Joanne Ng,John R Counsell,Els Henckaerts,Jonathan D Cooper,Ahad A Rahim,Julien Baruteau,Andrew M S Wong,Natalie Suff,Juliette M K M Delhove,Suzanne M K Buckley,Tristan R Mckay,Maha Tijani,Juan Antinao Diaz,Dany P Perocheau,Simon N Waddington,Michael Hughes

doi:10.1038/s41598-020-59075-3

Abstract

We have previously designed a library of lentiviral vectors to generate somatic-transgenic rodents to monitor signalling pathways in diseased organs using whole-body bioluminescence imaging, in conscious, freely moving rodents. We have now expanded this technology to adeno-associated viral vectors. We first explored bio-distribution by assessing GFP expression after neonatal intravenous delivery of AAV8. We observed widespread gene expression in, central and peripheral nervous system, liver, kidney and skeletal muscle. Next, we selected a constitutive SFFV promoter and NFκB binding sequence for bioluminescence and biosensor evaluation. An intravenous injection of AAV8 containing firefly luciferase and eGFP under transcriptional control of either element resulted in strong and persistent widespread luciferase expression. A single dose of LPS-induced a 10-fold increase in luciferase expression in AAV8-NFκB mice and immunohistochemistry revealed GFP expression in cells of astrocytic and neuronal morphology. Importantly, whole-body bioluminescence persisted up to 240 days. We have validated a novel biosensor technology in an AAV system by using an NFκB response element and revealed its potential to monitor signalling pathway in a non-invasive manner in a model of LPS-induced inflammation. This technology complements existing germline-transgenic models and may be applicable to other rodent disease models.

Highlights

Germline light-producing transgenic mice where luciferase expression is controlled by an endogenous promoter, a surrogate promoter or by a minimal promoter downstream of tandem, synthetic, transcription factor binding elements, are used to provide an in vivo readout of physiological and pathological processes[1,2]
We sought to determine the bio-distribution of GFP expression following neonatal (Post-neonatal day 1, P1) intravenous administration of AAV8-CMV-eGFP
We have shown for the first time that light-producing somatic-transgenic rodents can be produced by a single neonatal administration of an AAV8 biosensor

Summary

Introduction

Germline light-producing transgenic mice where luciferase expression is controlled by an endogenous promoter, a surrogate promoter or by a minimal promoter downstream of tandem, synthetic, transcription factor binding elements, are used to provide an in vivo readout of physiological and pathological processes[1,2]. Towards transgenic proteins[7], we were able to achieve organ-specific transduction by a single neonatal administration of the biosensor. For the first time we report the generation of light-emitting somatic transgenic rodents with a wider spread of transgene expression, following a single neonatal intravenous or intracranial administration of AAV8 biosensors. We validated the biosensing technology by administering LPS to model systemic inflammation and showed a significant increase in light emission. This technology will allow for expedited investigations regarding signalling pathways activated in disease processes and complement existing germline transgenic light-producing technology by maximising the use, and reducing the numbers of animals used in biomedical research

Methods

Results

Conclusion