CO-REGULATION OF MACROPHAGE INFLAMMATORY PHENOTYPE BY IRF5 AND RELA
Lead Research Organisation:
University of Oxford
Department Name: NDORMS
Abstract
Inflammation is a normal and self-limiting physiological response to infection and injury but can lead to extensive tissue damage and disability when elicited in excess or sustained. Pathological consequences of chronic inflammatory responses include a variety of diseases with huge social impact ranging from autoimmune diseases, such as rheumatoid arthritis to many forms of cancer. Macrophages are cells of the immune system which patrol the body and have the ability to recognise a number of different signals released during infection and damage. They are of central importance in the pathogenesis of chronic inflammatory diseases. Depending on the type of signal they receive, macrophages can acquire "aggressive" inflammatory phenotype and will destroy invading threats and defective cells. They secrete inflammatory molecules and set up an environment for expansion of other types of immune cells with inflammation propagating features. Other signals give rise to more "peaceful" macrophages that promote the growth and repair of damaged regions. For example, synovial lesions in rheumatoid arthritis are characterised by the pre-dominant presence of aggressive macrophages.
Recently my laboratory has made a potentially therapeutically important discovery and identified a molecular switch, called 'IRF5' that controls the aggressive phenotype of macrophages: it is highly expressed in aggressive macrophages and induces a characteristic gene expression and inflammatory molecule secretion profile. It is crucially important for establishing an inflammatory environment, associated with a number of autoimmune and inflammatory diseases, and promotes development of memory immune cells which produce even more harmful inflammatory mediators. We have also explored modes of IRF5 regulatory function and demonstrated that they involve functional and physical interactions with another molecular switch, called NF-kB RelA, which is important for proper immune function of both aggressive and peaceful macrophages. This project will test the hypothesis that interfering with IRF5, and in particular with its interactions with RelA, will override signals influencing aggressive macrophage development at sites of inflammation and promote their transformation into more peaceful phenotype, thus reducing inflammation.
Our aim is to ascertain:
1. which inflammatory molecules produced by aggressive macrophages are regulated by IRF5 and RelA and how is this control achieved on the molecular level?
2. can we block direct interactions between IRF5 and RelA and would this reduce production of the inflammatory molecules identified above?
The outcome of this study is expected to be the proof-of-principle demonstration of a new approach to controlling sustained inflammatory cytokine production, based on modulation of the recently identified major molecular switch. The follow up studies will look into the possibilities of other ways of modulating its activity and function, using chemicals, amendable to drug development. Taking account the essential role of macrophages in any immune and inflammatory condition, identification of major molecular switches that determine aggressive or peaceful function of macrophages may hold the key to new therapeutic interventions. It is an important area of research, as it may result in new class of treatment for a wide range of immune conditions. For example, blocking the function of these switches would dampen down damaging inflammation present in autoimmune diseases, while alternatively, inducing their function would boost the immune system in people with immunosuppression.
Recently my laboratory has made a potentially therapeutically important discovery and identified a molecular switch, called 'IRF5' that controls the aggressive phenotype of macrophages: it is highly expressed in aggressive macrophages and induces a characteristic gene expression and inflammatory molecule secretion profile. It is crucially important for establishing an inflammatory environment, associated with a number of autoimmune and inflammatory diseases, and promotes development of memory immune cells which produce even more harmful inflammatory mediators. We have also explored modes of IRF5 regulatory function and demonstrated that they involve functional and physical interactions with another molecular switch, called NF-kB RelA, which is important for proper immune function of both aggressive and peaceful macrophages. This project will test the hypothesis that interfering with IRF5, and in particular with its interactions with RelA, will override signals influencing aggressive macrophage development at sites of inflammation and promote their transformation into more peaceful phenotype, thus reducing inflammation.
Our aim is to ascertain:
1. which inflammatory molecules produced by aggressive macrophages are regulated by IRF5 and RelA and how is this control achieved on the molecular level?
2. can we block direct interactions between IRF5 and RelA and would this reduce production of the inflammatory molecules identified above?
The outcome of this study is expected to be the proof-of-principle demonstration of a new approach to controlling sustained inflammatory cytokine production, based on modulation of the recently identified major molecular switch. The follow up studies will look into the possibilities of other ways of modulating its activity and function, using chemicals, amendable to drug development. Taking account the essential role of macrophages in any immune and inflammatory condition, identification of major molecular switches that determine aggressive or peaceful function of macrophages may hold the key to new therapeutic interventions. It is an important area of research, as it may result in new class of treatment for a wide range of immune conditions. For example, blocking the function of these switches would dampen down damaging inflammation present in autoimmune diseases, while alternatively, inducing their function would boost the immune system in people with immunosuppression.
Technical Summary
Macrophages are immune cells that produce inflammatory mediators and are of central importance in the pathogenesis of chronic inflammatory diseases. The state of macrophage activation depends on the environmental factors and can change from pro- (M1) to anti-inflammatory (M2). M1 macrophages mediate resistance to pathogens and tissue destruction, whereas M2 macrophages promote tissue repair and remodelling as well as tumour progression. Mechanisms that control the switch of macrophage states present an attractive target for designing new therapeutic interventions that would modify sustained inflammatory macrophage activities without affecting their homeostatic function.
We have recently discovered that the transcription factor IRF5 is a major factor defining the pro-inflammatory M1 macrophage polarization. It directly regulates the secretion of specific inflammatory mediators characteristic of M1 macrophages (e.g. IL-12, IL-23, TNF, IL-1), that subsequently set up the environment for expansion of Th1/Th17 cells. We have also mapped molecular mechanisms of IRF5 function in regulation the TNF gene expression, such as direct binding to DNA and indirect recruitment via the formation of a protein complex with RelA. This proposal employs the state of the art functional genomics approaches (e.g. ChIP-Seq, RNA-Seq, EMSA-Seq) and established biochemical techniques (e.g. peptide mapping of protein-protein interaction interface) to identify a subset of genes important for M1 macrophage polarization and co-dependent on RelA-IRF5 interactions and to design molecules capable of breaking these interactions.
The proof of principle modulation of M1 macrophage polarization via interfering with RelA-IRF5 interactions may pave ways to future chemical drug design, which will selectively target the inflammatory response, ideally without having a deleterious effect on innate immunity which is an essential first line of defence against microbes.
We have recently discovered that the transcription factor IRF5 is a major factor defining the pro-inflammatory M1 macrophage polarization. It directly regulates the secretion of specific inflammatory mediators characteristic of M1 macrophages (e.g. IL-12, IL-23, TNF, IL-1), that subsequently set up the environment for expansion of Th1/Th17 cells. We have also mapped molecular mechanisms of IRF5 function in regulation the TNF gene expression, such as direct binding to DNA and indirect recruitment via the formation of a protein complex with RelA. This proposal employs the state of the art functional genomics approaches (e.g. ChIP-Seq, RNA-Seq, EMSA-Seq) and established biochemical techniques (e.g. peptide mapping of protein-protein interaction interface) to identify a subset of genes important for M1 macrophage polarization and co-dependent on RelA-IRF5 interactions and to design molecules capable of breaking these interactions.
The proof of principle modulation of M1 macrophage polarization via interfering with RelA-IRF5 interactions may pave ways to future chemical drug design, which will selectively target the inflammatory response, ideally without having a deleterious effect on innate immunity which is an essential first line of defence against microbes.
Planned Impact
With recently achieved understanding of the molecular mechanisms behind the set up of sustained inflammation, opportunities are now emerging to embark on a systematic and comprehensive analysis of this biological process and to develop new therapeutic strategies designed to control its magnitude and duration. As such, the proposed research could be advantageous for a wide range of beneficiaries, including industry and private sector; UK and EU policy-makers; patients with autoimmune conditions and charities supporting the research in inflammatory diseases; students and wider public interested in immune conditions.
1. Industry/private sector: The identification of amino acid groups involved in RelA-IRF5 interactions and the proof-of-principle modulation of specific gene expression by competing peptides provides a rational for a large-scale chemical library screen of compounds and/or drug design. This will benefit players in the industry and private sector, that are focused on chemical drug design and production, as they will be able to capitalise on our discovery and its implications furthered during the course of this project, by bringing about new drugs for chronic inflammatory and autoimmune diseases. We are currently engaged in exploring the possibilities of setting up a collaborative research programme with Novartis. Considering that the initial discovery and the research into ways of modulating IRF5 activity have been patented by the Imperial Innovations on our behalf, industry and private sector involvement will ultimately lead to fostering economic performance and competitiveness of the UK.
2. Policy-makers: The proposed research fully aligns with the MRC strategic priorities to train post-doctoral researchers in next-generation sequencing analyses while at the same time providing analytical capacity to UK-based experimental groups. The computational part of the proposal will be undertaking in close collaboration with CGAT, and thus it will contribute to training of computational biologists capable of analysing and interpreting next-generation sequencing data sets and will help to address the UK-wide shortage in this area. Our engagement in the EU scientific framework will ensure that the results of this project will be fully disseminated via the EU FP7 Model-In consortium web-site as well as communicated to the project officer, as the research which extends beyond the Model-In objective and together may shape the new FP7 funding calls.
3. Patients: IRF5, a molecule that determines whether key cells of the immune system promote inflammation or inhibit it, could hold the key to new treatments for autoimmune diseases such as rheumatoid arthritis and multiple sclerosis. The proposed research together with already ongoing investigations in the physiological role of IRF5 in mouse models of inflammatory diseases, such as house dust mite induced asthma (grant application to the American Asthma Foundation), collagen induced inflammatory arthritis (grant application to the Arthritis Research UK), inflammatory bowel disease (fellowship application to the Wellcome Trust), obesity related inflammation has the potential to bring about new drugs and therapeutic interventions and thus to contribute to the nation's health and wealth.
4. Students and wider public: Our communication plan presents the opportunity for a wider dissemination of the results via taught under-graduate and post-graduate courses, such as Advanced Topics in Molecular and Cellular Immunobiology, co-designed by the principal applicant for the 3rd year Imperial College under-graduates in Biology/Biochemistry/Immunology. We have an excellent working relationship with the press offices of Imperial College and Oxford University, as well as the number of immunology review journals and news agencies and which widely publicised our discovery of the role of IRF5 in macrophage polarization. These will be used to publicised the results of this study.
1. Industry/private sector: The identification of amino acid groups involved in RelA-IRF5 interactions and the proof-of-principle modulation of specific gene expression by competing peptides provides a rational for a large-scale chemical library screen of compounds and/or drug design. This will benefit players in the industry and private sector, that are focused on chemical drug design and production, as they will be able to capitalise on our discovery and its implications furthered during the course of this project, by bringing about new drugs for chronic inflammatory and autoimmune diseases. We are currently engaged in exploring the possibilities of setting up a collaborative research programme with Novartis. Considering that the initial discovery and the research into ways of modulating IRF5 activity have been patented by the Imperial Innovations on our behalf, industry and private sector involvement will ultimately lead to fostering economic performance and competitiveness of the UK.
2. Policy-makers: The proposed research fully aligns with the MRC strategic priorities to train post-doctoral researchers in next-generation sequencing analyses while at the same time providing analytical capacity to UK-based experimental groups. The computational part of the proposal will be undertaking in close collaboration with CGAT, and thus it will contribute to training of computational biologists capable of analysing and interpreting next-generation sequencing data sets and will help to address the UK-wide shortage in this area. Our engagement in the EU scientific framework will ensure that the results of this project will be fully disseminated via the EU FP7 Model-In consortium web-site as well as communicated to the project officer, as the research which extends beyond the Model-In objective and together may shape the new FP7 funding calls.
3. Patients: IRF5, a molecule that determines whether key cells of the immune system promote inflammation or inhibit it, could hold the key to new treatments for autoimmune diseases such as rheumatoid arthritis and multiple sclerosis. The proposed research together with already ongoing investigations in the physiological role of IRF5 in mouse models of inflammatory diseases, such as house dust mite induced asthma (grant application to the American Asthma Foundation), collagen induced inflammatory arthritis (grant application to the Arthritis Research UK), inflammatory bowel disease (fellowship application to the Wellcome Trust), obesity related inflammation has the potential to bring about new drugs and therapeutic interventions and thus to contribute to the nation's health and wealth.
4. Students and wider public: Our communication plan presents the opportunity for a wider dissemination of the results via taught under-graduate and post-graduate courses, such as Advanced Topics in Molecular and Cellular Immunobiology, co-designed by the principal applicant for the 3rd year Imperial College under-graduates in Biology/Biochemistry/Immunology. We have an excellent working relationship with the press offices of Imperial College and Oxford University, as well as the number of immunology review journals and news agencies and which widely publicised our discovery of the role of IRF5 in macrophage polarization. These will be used to publicised the results of this study.
Organisations
- University of Oxford (Collaboration, Lead Research Organisation, Project Partner)
- UNIVERSITY OF OXFORD (Collaboration)
- University of California, Los Angeles (UCLA) (Collaboration)
- Medical Research Council (MRC) (Collaboration)
- European Institute of Oncology (IEO) (Collaboration)
- IMPERIAL COLLEGE LONDON (Collaboration)
- MERCK (Collaboration)
Publications
Ryzhakov G
(2015)
Activation and Function of Interferon Regulatory Factor 5
in Journal of Interferon & Cytokine Research
DeLaney AA
(2019)
Caspase-8 promotes c-Rel-dependent inflammatory cytokine expression and resistance against Toxoplasma gondii.
in Proceedings of the National Academy of Sciences of the United States of America
Del Fresno C
(2013)
Interferon-ß production via Dectin-1-Syk-IRF5 signaling in dendritic cells is crucial for immunity to C. albicans.
in Immunity
Weiss M
(2015)
IRF5 controls both acute and chronic inflammation.
in Proceedings of the National Academy of Sciences of the United States of America
Weiss M
(2013)
IRF5 is a specific marker of inflammatory macrophages in vivo.
in Mediators of inflammation
Saliba DG
(2014)
IRF5:RelA interaction targets inflammatory genes in macrophages.
in Cell reports
Eames HL
(2012)
KAP1/TRIM28: an inhibitor of IRF5 function in inflammatory macrophages.
in Immunobiology
Murray PJ
(2014)
Macrophage activation and polarization: nomenclature and experimental guidelines.
in Immunity
Eames H
(2014)
Macrophages: Biology and Role in the Pathology of Diseases
Title | Photo exhibition |
Description | "Scientists at work" photo exhibition in the local gallery |
Type Of Art | Artwork |
Year Produced | 2012 |
Impact | Members of the group organising a photo club and taking monthly photos of interest. The topic "Scientists at work" was presented at the local gallery in London |
Description | Kennedy Institute Trustees Research Fund |
Amount | £120,000 (GBP) |
Funding ID | KIR06-2013 |
Organisation | University of Oxford |
Department | Kennedy Institute of Rheumatology |
Sector | Academic/University |
Country | United Kingdom |
Start | 09/2013 |
End | 09/2017 |
Description | Kennedy Institute Trustees Research Fund |
Amount | £100,000 (GBP) |
Organisation | University of Oxford |
Department | Kennedy Institute of Rheumatology |
Sector | Academic/University |
Country | United Kingdom |
Start | 09/2013 |
End | 09/2015 |
Description | NovoNordisk_1 |
Amount | £100,000 (GBP) |
Funding ID | Metabolites |
Organisation | Novo Nordisk |
Sector | Private |
Country | Denmark |
Start | 01/2016 |
End | 01/2018 |
Title | ChIP-Seq |
Description | ChIP-Seq data for a number of transcription factors and polymerase II in M1 macrophages |
Type Of Material | Database/Collection of Data/Biological Samples |
Provided To Others? | No |
Impact | map of binding sites for transcription factors essential for interpretation of gene expression data |
Title | expression arrays |
Description | gene expression datasets for wild type bone marrow derived macrophages and those deficient in specific transcription factors |
Type Of Material | Database/Collection of Data/Biological Samples |
Provided To Others? | No |
Impact | critical for understanding the gene target of important transcription factors |
Description | AH |
Organisation | Medical Research Council (MRC) |
Department | MRC Functional Genomics Unit |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | ChIP-Seq datasets for transcription factors |
Collaborator Contribution | bioinformatic support for the genome-wide analysis |
Impact | MRC project grant MR/J0018991/1 IRF5:RelA interaction targets inflammatory genes in macrophages. Saliba DG, Heger A, Eames HL, Oikonomopoulos S, Teixeira A, Blazek K, Androulidaki A, Wong D, Goh FG, Weiss M, Byrne A, Pasparakis M, Ragoussis J, Udalova IA. Cell Rep. 2014 Sep 11;8(5):1308-17 |
Start Year | 2011 |
Description | CL |
Organisation | Imperial College London |
Department | National Heart & Lung Institute (NHLI) |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | question and plan of the reseacrh, expertise in molecular technologies |
Collaborator Contribution | expertise in animal models of asthma |
Impact | AAF funding; manuscript Mucosal Immunology |
Start Year | 2011 |
Description | FP |
Organisation | University College Oxford |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | expertise in IRF5 and neutrophil and macrophage biology |
Collaborator Contribution | expertise in IBD and colitis animal models |
Impact | joint DPhil studentships 2013-2016; 2017-2022 co-PI on the MRC project grant |
Start Year | 2013 |
Description | GN |
Organisation | European Institute of Oncology (IEO) |
Country | Italy |
Sector | Academic/University |
PI Contribution | Intellectual contribution to DNA-protein interactions and genome analysis |
Collaborator Contribution | Intellectual contribution to the aspects of gene regulation; transferring chromatin immunoprecipitation and 3C techniques |
Impact | Grants: 1. FP7-EU grant 222008 "Genomic determinants of inflammation" 2. Royal Society joint grant "Examining DNA sequence selectivity by alternative NF-kappaB proteins" 3. Horizon 2020 PCH03 proposal "Unifying basis of Chronic Inflammatory Diseases" submitted |
Start Year | 2006 |
Description | JR |
Organisation | University of Oxford |
Department | Wellcome Trust Centre for Human Genetics |
Country | United Kingdom |
Sector | Charity/Non Profit |
PI Contribution | I have initially set up and developed high throughput analysis of transcription factor - DNA interactions in vitro, further optimised and developed by the collaborator's team. |
Collaborator Contribution | Using the genomic platform developed in this collaboration, Ragoussis team has produced our analysis of their functional properties and conservation. |
Impact | Publications: 1. PMID: 17785540 2. PMID: 17785540 3. PMID: 16888364 4. Linnell J, Mott R, Field S, Kwiatkowski DP, Ragoussis J, Udalova IA. Quantitative high-throughput analysis of transcription factor binding specificities. Nucleic Acids Res. 2004 Feb 27;32(4):e44. PMID: 14990752 Grants: 1. FP7-EU grant 222008 "Genomic determinants of inflammation" 2. MRC collaborative grant G0700818 |
Description | NP |
Organisation | University of Oxford |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | expertise in IRF5 biology |
Collaborator Contribution | expertise in transcriptional termination |
Impact | joint DPhil studentship 2013-2016 |
Start Year | 2013 |
Description | RR |
Organisation | Merck |
Country | Germany |
Sector | Private |
PI Contribution | IRF5 interactome |
Collaborator Contribution | ALIS screen for IRF5 binding sites for small molecules |
Impact | pending |
Start Year | 2012 |
Description | SS |
Organisation | University of California, Los Angeles (UCLA) |
Country | United States |
Sector | Academic/University |
PI Contribution | reseacrh question and expertise in IRF5 biology and gene regulation |
Collaborator Contribution | chromatin remodelling |
Impact | joint experiments |
Start Year | 2012 |
Title | TREATMENT AND SCREENING |
Description | A method of treating a patient having an autoimmune disease or a Th1 polarising infection or a condition associated with inflammation other than asthma or allergy, the method comprising administering to the patient a therapeutically effective amount of an inhibitor of Interferon Regulatory Factor 5 (IRF5). |
IP Reference | WO2012093258 |
Protection | Patent application published |
Year Protection Granted | 2012 |
Licensed | No |
Impact | potential industrial collaborations |
Title | FACS |
Description | Use antibodies to IRF5 as a marker of inflammatory macrophages (FACS staining) |
Type | Diagnostic Tool - Imaging |
Current Stage Of Development | Initial development |
Year Development Stage Completed | 2013 |
Development Status | Under active development/distribution |
Impact | May facilitate profiling of very heterogeneous immune cells in norm and during disease progression |
Title | Peptide |
Description | Identification of a peptide potentially capable of inhibiting specific IRF5 activities |
Type | Therapeutic Intervention - Cellular and gene therapies |
Current Stage Of Development | Initial development |
Year Development Stage Completed | 2013 |
Development Status | Actively seeking support |
Impact | novel modulatory agent capable of targetting IRF5 intercations with co-factor, is efficacy in cellular assays is confirmed can be used to block inflammatory response |
Description | Photo exhibition |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Local |
Primary Audience | Public/other audiences |
Results and Impact | Local people attended a photo exhibition designed to demonstrate Scientists at work summer placements at the Institute for school children |
Year(s) Of Engagement Activity | 2012 |