Pericellular mechanisms of fibrillin microfibril assembly.

Lead Research Organisation: University of Manchester
Department Name: School of Biological Sciences

Abstract

Fibrillin microfibrils are filamentous structures laid down by cells as part of the 'extracellular matrix (ECM)'. They form bundles of microfibrils that interact with cells and also form the framework for the formation of 'elastic fibres', which endow the essential property of elastic recoil on dynamic tissues such as blood vessels, lungs, skin and ligaments. The importance of fibrillin is clearly highlighted by the many serious diseases that are caused by genetic defects in fibrillin (e.g. Marfan syndrome, which is associated with life-threatening cardiovascular defects), and by the degeneration of microfibrils in ageing and diseases of blood vessels, lungs (emphysema), loss of skin elasticity, and certain eye defects. Despite their essential nature, it is still not understood how microfibrils form, which has severely limited treatment advances. This proposal is to build on exciting new discoveries from my group which give important new insights into their assembly and function. The study will provide new insights into how mutations in fibrillin-1 cause severe heritable diseases, and form the basis for improved strategies to restore microfibrils to tissues with compromised elasticity. The project is of great importance to regenerative medicine, which is an MRC priority because there is a major unmet clinical need to develop new treatments to restore function to compromised elastic tissues and organs. My group is ideally placed to conduct this specialised research because we are internationally-renowned for our expertise and discoveries in fibrillin/elastic fibre biology, and we will build on our have recent discovery of cell type-specific mechanisms that throw new light on this complex process. Thus it is very timely and directly addresses the MRC Priority 'Resilience, Repair and Replacement'.

Technical Summary

We will determine how the cell-matrix interface of epithelial and mesenchymal cells directs assembly of fibrillin microfibrils, and thus elastic fibres. The objective is to deliver a step-change in ability to restore elastic tissue function following damage or disease, or degenerative ageing changes.
How HS/syndecan-4, FN and alpha5beta1 integrin enable microfibril assembly;
- Compare in vitro and cell-driven assembly of fibrillin-1 with/without HS (electron microscopy; biochemically; determine role of syndecan-4 (siRNA, mutagenesis, domain swap with syndecans-1/-2; real-time microscopy to track microfibrils); contribution of fibronectin (mutagenesis; fibronectin fragments);
- How similar mechanisms regulate LTBP-1 deposition, and thus TGFbeta bioavailability;
- How epithelial cell-cell interactions regulate ECM assembly.
How ADAMTS10 supports microfibril assembly;
- How ADAMTS10 influences fibrillin-1 assembly and higher-order microfibril organisation (electron microscopy; biochemical/biophysical analyses);
- How WMS mutations alter microfibril organisation and function (full-length mutant fibrillin-1; assembly assays; microfibril deposition by cells expressing mutant WMS fibrillin-1 (Talen; fluorescence/ real-time microscopy; light sheet microscopy for quantitative live cell imaging).
- How ADAMTS10 stabilises cell-cell junctions (effects on microfibril organisation).
Design therapeutic strategies to repair elastic tissues.
- Test receptor-activating antibodies and fibronectin/HS/ADAMTS10 products (co-culture tissue equivalents);
- Regulate receptor activity (antibodies, siRNAs, ECM products in ECM-containing peptide hydrogels, nano-constructs; with Biomaterials, Manchester). Viral transduction, non-viral cationic liposomes or direct exposure to plasmid DNA;
- Elasticity of tissue equivalents (microfibril content; nanoindentation, acoustic microscopy).

Planned Impact

This study is to elucidate how epithelial and mesenchymal cells differentially assemble fibrillin microfibrils, and thus the elastic fibres which provide essential elastic recoil to tissues such as blood vessels, lungs, skin and ligaments. It directly addresses the MRC Priority 'Resilience, Repair and Replacement' because it will determine the mechanistic basis of their deposition, and therefore how to repair and regenerate elastic tissues. It will benefit:
(1) Biomedical scientists and the UK regenerative medicine community
The study will deliver essential new insights into how the cellular microenvironment controls the assembly of extracellular matrix, and thus how cells make and remodel tissues. The particular focus is fibrillin microfibrils which form the template for elastic fibres that provide indispensible elastic recoil to dynamic tissues. This knowledge is urgently needed, given that degeneration of elastic tissues is a prominent feature of many of the major diseases of man.
Realising the benefits: Our research will lead to translational applications that will be developed through the Manchester Academic Health Science Centre, and through the UK Regenerative Medicine Platform hub (UKRMP) 'Exploiting and engineering the stem cell niche' (Kielty is a partner). Further added value will be achieved through research collaborations in Manchester, and nationally and internationally, and data and reagent sharing, especially with UKRMP colleagues. We will also extend links with MIMIT (Manchester: Integrating Medicine and Innovative Technology; linked to CIMIT, Boston USA), which develops clinical solutions for tissue repair and related unmet clinical needs.
(2) Biopharma
Research leading to elastic fibre repair is a high priority in regenerative medicine/tissue engineering and Biopharma companies, because effective new therapeutic products are urgently needed.
Realising the benefits: University of Manchester Intellectual Property (UMIP) will support the commercialisation of research emerging from this study, e.g. selling/licensing of reagents, provision of research expertise, in-house assays/techniques, co-development of technologies or licensing of IP.
(3) Graduate training
The application of cell-matrix biology in regenerative medicine is a priority of the University of Manchester (UoM). We have proposed an integrated graduate training by research in regenerative medicine that integrates biomedical sciences with clinical application (EPSRC-MRC Centre for Doctoral Training in Regenerative Medicine; invited submission, in review). Through my internationally-leading MRC-funded microfibril/elastic fibre research and graduate opportunities, a new generation of researchers will be trained to the very highest standards in the cell-matrix biology of regenerative medicine, and its clinical applications.
Realising the benefits: Major impact will be achieved by training graduates in the scientific methods and translational applications required to understand how the microenvironment (niche) directs cells to remodel and repair elastic tissues.
(4) General Public
This research programme is a powerful platform to inform the general public about our regenerative medicine activities, in public meetings and internet fora.
Realising the benefits: I will write review articles for popular press and student science magazines; train my PhD students in communications and public engagement; participate in Manchester Science Week; develop outreach materials to inform local, national and international audiences, and patient groups.

Publications

10 25 50
 
Description The role of ADAMTS-like proteins in fibrillin microfibril assembly
Amount £487,694 (GBP)
Funding ID BB/R008221/1 
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 02/2018 
End 01/2021
 
Description American Society for Matrix Biology Annual Meeting 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Type Of Presentation poster presentation
Geographic Reach International
Primary Audience Other audiences
Results and Impact A talk was presented at the ASMB meeting in Las Vegas, USA in October 2018 by Clair Baldock.

A talk was presented at the ASMB meeting in St Petersburg, Florida in November 2016 by Clair Baldock and a poster presented by Dr Michael Lockhart.

A poster was presented at the ASMB meeting in Cleveland, USA in October 2014 by PDRA Dr Christopher Bayley. His poster attracted many visitors who discussed his findings and had suggestions for collaboration.

Sparked a new collaboration to explore ideas further.
Year(s) Of Engagement Activity 2014,2016,2018
URL http://www.asmb.net/Pastmeetings.php
 
Description Chair of Elastin, Elastic Fibers and Microfibrils Gordon Research Conference 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Chair of the Elastin, Elastic Fibers and Microfibrils Gordon Research Conference, July 2017 at the University of New England, Maine USA. 116 attendees including academic, industry and government employees. In addition to organising and chairing the meeting, fundraising of >$80,000 was achieved including an NIH grant. Four members of my lab presented posters, one won the poster prize, one member of my lab gave a short-talk and another chaired a session.
Year(s) Of Engagement Activity 2017
URL https://www.grc.org/elastin-elastic-fibers-and-microfibrils-conference/2017/
 
Description Daresbury Science Festival 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact My laboratory hosted a stand at Daresbury Laboratories STFC for a week in July 2016 to illustrate research performed through STFC (ie at synchrotrons). We had ~500 pupils per day visit the stand from Key Stage 2 to Key Stage 5 and at the weekend the site was open to the public attracting thousands of visitors.
Year(s) Of Engagement Activity 2016
URL http://www.stfc.ac.uk/public-engagement/activities-for-the-public/visit-daresbury-laboratory/daresbu...
 
Description Elastin and Microfibrils Gordon Research Conference 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Other audiences
Results and Impact Biannual invited talk at the Elastin GRC for PI Clair Baldock since 2003. Talk facilitated discussion of the use of SAXS for other elastic fibre proteins.

Elected vice-chair of GRC for 2015 (chair in 2017).
Collaboration on SAXS of tropoelastin has led to 2 PNAS, 1 JBC and 1 Matrix Biology papers to date.
Talks led to invitation to visit two Institutions in Canada (Sick Kids Hospital, Toronto and Simon Fraser University, Vancouver) and to Shriners Hospital in Portland in 2011.
Year(s) Of Engagement Activity Pre-2006,2006,2007,2009,2011,2013,2015,2017,2019
 
Description European Elastin Meeting 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact PI Clair Baldock and group members attend biannual European Elastin Meetings to network with European community and raise profile of research.

Invitation to participate in a Marie Curie Sklodowska ITN network and elected vice-chair of the Elastin Gordon conference for 2015 (Chair in 2017).
Year(s) Of Engagement Activity 2008,2010,2012,2014,2016,2018
 
Description Matrix Biology Europe 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Talks and posters stimulated discussion.

Mukti Singh (BBSRC DTP PhD student) was awarded a poster prize.

After talks I was asked to talk at National Societies including the German Connective Tissues Society Meeting in Cologne in 2011 and the French Connective Tissue Society Meeting in 2012.
Led to participation in an application for a Marie Curie Sklodowska ITN network.
Year(s) Of Engagement Activity 2010,2012,2018