Novel and bespoke mouse models for dissecting neurodegenerative disease

Lead Research Organisation: MRC Mammalian Genetics Unit

Abstract

This four year Programme has appointed a Band 3 scientist, plus a part-time technician, and job offers have been made to a full-time technician and a postdoc who will take the job subject to receiving a visa. The lab aims to develop, characterise and export novel mouse models to named researchers with expertise in Alzheimer disease (AD) and Down syndrome (AD-DS), amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD); the Band 3 scientist’s expertise lies in Parkinson’s disease. The mouse models are (1) urgently needed bespoke mutants to address specific biological questions and (2) humanised mutants developed under a longer-term program aiming to optimise modelling of neurodegenerative disease.

Technical Summary

After finding a novel human mutant gene, usually next is to produce a genetically modified mouse
to recapitulate the disease in a tractable experimental system. Mice may not perfectly model
human late-onset disorders (such as AD, AD-DS, FTD, ALS), but they are irreplaceable for
studying molecular pathology and developing therapies including genetic and stem-cell
based treatments. We can also make useful primary cell culture systems from mouse
models, as many cell types cannot yet be derived from human iPSCs or embryonic stem
cells (ESCs).

Current technologies such as the CRISPR/Cas9 system, make it relatively straight-forward to
model the majority of human monogenic disorders in mice, and to study likely genetic
modifiers by creating the same alleles in mice that are potential disease modulators, as
indicated from GWAS studies, in humans1. Thus we have an unprecedented range of mouse
models available, including from global collaborations such as the International Knockout
Mouse Consortium (IKMC), and we have massive phenotype datasets (for example, from the
International Mouse Phenotyping Consortium, IMPC2) that give us unexpected new insights.
These resources efficiently increase the pace of biomedical research, but cannot address
specific biological questions that require bespoke mouse models. Such models may be
challenging, yet feasible, to make, and would be used immediately by neuroscientists, but
are difficult to fund because they may be individually expensive to create and fully analyse.

Modelling late onset neurodegenerative disease in mice remains challenging. The
common neurodegenerative diseases we study are mainly sporadic but between ~10% (for
example, ALS, AD) and 40% (FTD) are genetic, usually dominant. Such familial diseases
give us a route to understanding sporadic disease, and are modelled by transgenics,
generally with a concatamer of transgenes overexpressing a mutant protein from a cDNA
under the control of a non-endogenous promoter. The level of mutant protein may correlate
with disease severity and the advantage of this type of model is development of pathology
within the lifespan of a mouse3. For example, the most widely-used ALS model remains the
human mutant SOD1G93A transgenic produced in 19944, which overexpresses human mutant
SOD1 protein by up to 24 fold above the endogenous mouse SOD1 protein3, 4.

However, transgenics also have phenotypes arising from overexpression per se, as shown
when characterising mice that overexpress the wildtype human protein (which may be a valid
disease causing mechanism). BAC transgenics are a refinement giving expression from
human genomic DNA, usually only 1-3 copies with the endogenous promotor3, 5, and show
that complex human splicing patterns, such as that of the Tau protein, can be recreated in
mice6. However, the BAC transgenic low ‘dose’ of protein often gives mild phenotypes that
mimic only the earliest stages of human neurodegenerative disease and show molecular
changes without overt symptoms6; thus although these animals give insight into pathology,
they may not be adopted by the community because the mice do not succumb to overt
symptoms or endstage disease. More sophisticated ways of working with these mouse
models may lead to dissecting early-stage pathology/biomarkers, rather than studying late-stage disease pathways, and even to finding compensatory pathways in mice that may be
relevant for human therapeutics.

Publications

10 25 50
 
Title A new mouse model of motor neuron degeneration (FUS ALS) 
Description A new genetically engineered mouse model of FUS ALS 
Type Of Material Model of mechanisms or symptoms - mammalian in vivo 
Year Produced 2017 
Provided To Others? Yes  
Impact Several labs now working with this model 
 
Title Engineered mouse FUS humanised ES cells. 
Description Mouse cell line that we may analyse rather than working with whole animals, thus helps with aims of NC3Rs. 
Type Of Material Data analysis technique 
Provided To Others? No  
Impact None yet. 
 
Title FUS homozygotes MEFs 
Description Working with a mouse model, an in vivo model, to produce IMMORTILISED cell lines so that we can drop our animal useage. 
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? Yes  
Impact Reduced mouse numbers 
 
Description Analysis of the FUS mouse translatome, Fratta, UCL 
Organisation University College London
Department Marie Curie Palliative Care Research Department
Country United Kingdom 
Sector Academic/University 
PI Contribution contribution of the unique FUS Delta14 mouse model
Collaborator Contribution RiboTagging and ChatCre breeding to pull down polysomes from the Delta14 mouse
Impact Multidisiplinary output. No outcomes yet as just started.
Start Year 2016
 
Description Labs at UCL for bespoke mouse models of neurodegeneration 
Organisation University College London
Department Department of Neuroscience, Physiology and Pharmacology
Country United Kingdom 
Sector Academic/University 
PI Contribution Genome engineering expertise
Collaborator Contribution In depth knowledge of specific forms of neurodegeneration Fratta, Isaacs, Greensmith, Schiavo, Wiseman.
Impact None yet.
Start Year 2017
 
Description MMON 
Organisation MRC Harwell
Country United Kingdom 
Sector Academic/University 
PI Contribution Collaboration with the Mouse Models of Neurodegeneration lab at MRC Harwell, analysis of homozygous and heterozygous mice
Collaborator Contribution Breeding, inbreeding onto another background, and phenotypic analysis of homozygous and heterozygous mice.
Impact Inbred mice on different backgrounds. Cohorts of mice of different ages, sex-matched with littermate controls, wildtype, heterozygous, homozygous, for phenotypic analysis. Analysis of different phenotypes ranging from behavioural through to physiological.
Start Year 2017
 
Description  
IP Reference  
Protection Protection not required
Year Protection Granted
Licensed Yes
Impact Antibody for FUS Delta 14 sent out for academic use.
 
Description DS special interest group 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Professional Practitioners
Results and Impact Wiseman F, LonDownS Consortium (2018) Understanding Down syndrome using Alzheimer's mouse models. Dementia in intellectual disabilities, Special Interest Group Meeting, London, London UK.

Talk to mix of medical and other professionals working with peoplewith Down syndrome.
Year(s) Of Engagement Activity 2018
 
Description Edgar talk to Parkinson's patients at Open Day 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Patients, carers and/or patient groups
Results and Impact Open day at MRC Harwell; PI gave a talk to Parkinson's disease patients and carers.
Year(s) Of Engagement Activity 2017
 
Description UCL Postgraduate symposium poster 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact De Giorgio A, Devoy A, Milioto C, Zhu F, MacKenzie K, Acevedo Arozena A, Fisher EMC (2018) Humanising the mouse Tardbp gene. UCL Sixth Annual Postgraduate Research Symposium, London, UK

Poster presented to postgraduates outside field.
Year(s) Of Engagement Activity 2018