Effects of Nod-like receptor activity on protective immunity against Salmonella infection

Lead Research Organisation: University of Cambridge
Department Name: Veterinary Medicine

Abstract

Infectious diseases remain major problems with significant economic and social impact despite the availability of antimicrobials and vaccines. The development of resistance to antimicrobials by microorganisms means that alternative control measures are required. Control of food-borne bacterial infections that infect people is particularly challenging because some bacteria can live in livestock without causing any harmful effects under the right circumstances (for example species of Salmonella enterica or Campylobacter in chickens) yet cause disease in humans. How this species-specific bacterial "tolerance" occurs is not understood which makes design of control strategies difficult. Vaccination strategies have reduced disease incidence for some bacteria, but many current vaccines are not ideal. Alternative approaches to combat infectious disease in livestock are to use selective breeding for disease resistance or to generate genetically modified animals to alter their susceptibility to infection. To design suitable control strategies it is essential to understand how bacteria co-exist with livestock.
Bacteria are recognised in humans and animals by specialised proteins called pattern recognition receptors (PRRs) to activate anti-bacterial immunity. There are major differences in the repertoires of PRRs and in the bacteria they detect between different species of mammals and birds. Our previous BBSRC funded research has found that some of the PRRs specifically the Nod Like Receptors (NLRs) NLRC4 and Nod2, that are missing from chickens, are important regulators of immune responses against Salmonella. Using comparative studies between mouse and chicken cells this grant will identify the NLR-signalling pathways driving the host response to infection. By expressing human NLRC4 or Nod2 in chicken cells and in chickens we will determine whether these PRRs contribute to why humans and animals react differently to the same salmonellae.

Technical Summary

Infectious diseases remain major problems with significant economic and social impact despite the availability of antimicrobials and vaccines. The development of resistance to antimicrobials by microorganisms means that alternative control measures are required. Control of food-borne zoonotic bacterial infections is particularly challenging because some bacteria can behave like commensals in livestock under the right circumstances (for example Salmonella species) yet are pathogens in humans. The molecular basis for this species-specific bacterial "tolerance" is not understood which makes design of control strategies difficult. Vaccination strategies have reduced disease incidence for some bacteria, but many current vaccines have been generated empirically which often results in a product with limited efficacy. Alternative approaches to combat infectious disease in livestock are to use selective breeding for disease resistance traits or to generate genetically modified animals to alter their susceptibility to infection. To design suitable control strategies it is essential to determine how pathogens interface with host immunity

Pathogen recognition by host pattern recognition receptors (PRRs) activates innate and adaptive immunity. There are major differences in the repertoires of PRRs and in how they respond to ligands between different species of mammals and birds. The Nucleotide Oligomerisation Domain (Nod)-like receptors (NLRs) show wide species differences in repertoire with mice having 30, humans 22, and chickens 7. Our data show that the NLRs NLRC4 and Nod2 that are missing from chickens are important regulators of TH1 immunity against Salmonella infection. Using comparative studies between mouse and chicken cells this research will identify the NLR-signaling pathways driving the host response to infection. By expressing human NLRC4 or Nod2 in chickens we will determine whether these PRRs contribute to species-specific host responses to salmonellae.

Planned Impact

A central part of any strategy to reduce diseases such as salmonellosis must be intervention to induce the immune system to prevent infection or to clear infection rapidly. This is currently achieved by vaccination or immunotherapy. Alternative strategies include breeding animals for disease resistance traits or transgenic expression of genes to enhance bacterial clearance. To generate new vaccines, improve current vaccines or to pursue genetic modification we must understand the mechanisms by which immunity is induced, and this research will provide an essential element of that knowledge.
Impact will be delivered to beneficiaries in the commercial private sector and in the wider public sector. This grant proposal is supported by an IPA agreement with Pfizer because the project will generate information that can be used to inform rational vaccine development against salmonellosis and potentially other bacterial pathogens (by 36 months). The grant is also likely to generate information as to which receptors are important for recognising salmonellae in species of commercial importance i.e. chickens (by 24 months). An added benefit of this grant is that the Nod-like receptors that are activated by salmonellae in mice are also conserved in humans: therefore this grant will generate data which may improve human vaccines against salmonellosis and will be of interest to the medical pharmaceutical industry (by 24 months). Development of improved vaccines and vaccine strategies will enhance UK economic competitiveness in animal and medical heath programs. The grant will have impact on the wider public sector by continuing our program of scientific communication. Our laboratories hosts up to 6 school children a year on work placements to engage them in the fundamentals of scientific research. Our research work is communicated in public forums such as the Cambridge science fair and during open days at the veterinary school. Dr Bryant is working closely with Dr Chris Smith of BBC Radio Cambridgeshire's Naked Scientists program to feature work on zoonotic diseases, with an emphasis on bacterial pathogens, and on multidisciplinary research (http://www.thenakedscientists.com/HTML/podcasts/show/2010.07.11/). The research in this grant will contribute to the zoonosis interest of the radio program and this should be realised within 24 months of starting the project. The grant will contribute to influencing policy decisions via Professor Maskell's membership of the General Advisory Committee on Science (GACS) at the Food Standards Agency and Dr Bryant's membership of the Veterinary Products Committee of the Veterinary Medicines Directorate. This project will develop new technical skills for the two postdoctoral researcher associates (PDRAs). Dr Tourlomousis will learn in vitro cell culture techniques to complement his skills in in vivo biology. The second, junior PDRA will use a range of skills including molecular techniques and in vitro cell culture skills and will receive training in these areas. Both PDRAs will learn imaging techniques through Dr Bryant's on-going collaboration with Dr Cicuta in Physics which forms part of her BBSRC Research Development fellowship. Both PDRAs will be involved in the public communication activities of this project. PDRAs will also attend BBSRC media training courses and University-run workshops on grant writing, communication skills and software training to develop their transferrable skills.

Publications


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Achouri S (2015) The frequency and duration of Salmonella-macrophage adhesion events determines infection efficiency. in Philosophical transactions of the Royal Society of London. Series B, Biological sciences
Gay NJ (2014) Assembly and localization of Toll-like receptor signalling complexes. in Nature reviews. Immunology
Man SM (2014) Inflammasome activation causes dual recruitment of NLRC4 and NLRP3 to the same macromolecular complex. in Proceedings of the National Academy of Sciences of the United States of America
Man SM (2014) Inflammasome activation causes dual recruitment of NLRC4 and NLRP3 to the same macromolecular complex. in Proceedings of the National Academy of Sciences of the United States of America
 
Description In this grant we have determined how Salmonella is recognised in the host through specialised receptors called Pattern Recognition Receptors (PRRs). We have shown how PRRs control Salmonella infections in animals. We have also shown that the protective immune response against this bacterium is influenced by PRRs. The protective immune response is the mechanism by which vaccines work and our data will be useful in designing anti-salmonella vaccines. We have found that critical members of the PRRs which recognise Salmonella are missing in chickens. We have identified that the chicken has some compensatory mechanisms to detect Salmonella, but is, overall, less able to detect this bacterium.
Exploitation Route Optimisation of anti-Salmonella vaccination strategies in humans and poultry.
Guidance as to the provision of the best adjuvant to enhance vaccine efficacy against Salmonella in humans and poultry.
Guidance on potential disease resistance traits for poultry breeders.
Fundamental information on the innate and adaptive response against Salmonella in humans and poultry for the scientific community.
Sectors Agriculture, Food and Drink,Communities and Social Services/Policy,Healthcare,Pharmaceuticals and Medical Biotechnology
 
Description Our fundings have been disseminated to a number of different groups of stakeholders and the general public. For example in 2015 our work on poultry immunology was delivered to the Poultry Conference in Belfast to poultry veterinary surgeons, poultry breeders and other stakeholders in January 2015. I also co-hosted an antimicrobial resistance fora to the general public at the Cambridge Science Fair (March 2015) and I gave a talk on the impact of antimicrobial resistance to the Cambridge Enterprise network (a group of Cambridge entrepreneurs) in November. I have also talked about our work at GSK which has led to significant collaborative funding.
First Year Of Impact 2015
Sector Communities and Social Services/Policy,Education,Healthcare,Pharmaceuticals and Medical Biotechnology
Impact Types Societal,Economic
 
Description Elion and Black Immunology Catalyst Sabbatical Award
Amount £226,000 (GBP)
Organisation GlaxoSmithKline (GSK) 
Sector Private
Country Global
Start 11/2016 
End 10/2019
 
Description Interdisciplinary Research Grant
Amount £204,000 (GBP)
Funding ID ARUK-IRG2014-13 
Organisation Alzheimer's Research UK 
Sector Charity/Non Profit
Country United Kingdom of Great Britain & Northern Ireland (UK)
Start 02/2015 
End 01/2018
 
Description Royal Society Wolfson Refurbishment Scheme
Amount £267,000 (GBP)
Organisation The Royal Society 
Sector Academic/University
Country United Kingdom of Great Britain & Northern Ireland (UK)
Start 03/2016 
End 02/2018
 
Description Wellcome Trust Investigator Award
Amount £2,200,000 (GBP)
Organisation The Wellcome Trust Ltd 
Department Wellcome Trust Senior Investigator Award
Sector Private
Country United Kingdom of Great Britain & Northern Ireland (UK)
Start 01/2016 
End 12/2021
 
Description Astra Zeneca collaboration 
Organisation Athersys Inc.
Department Respiratory, Inflammation and Autoimmunity
Country United States of America 
Sector Private 
PI Contribution We are running a collaborative project with Cambridge Enterprise and AZ to look for novel drugs to treat allergic respiratory disease. We perform the functional biology
Collaborator Contribution Provision of compounds and expertise
Impact None yet
Start Year 2014
 
Description Bruce Beutler, The Scripps, USA 
Organisation Scripps Research Institute
Country United States of America 
Sector Charity/Non Profit 
PI Contribution Collaboration with The Scripps, USA
Start Year 2000
 
Description Continued Collaboration with University of Massachusetts Medical Schoo 
Organisation University of Massachusetts (UMass)
Department University of Massachusetts Medical School
Country United States of America 
Sector Academic/University 
PI Contribution Continuation of existing collaboration
Collaborator Contribution Provision of cell lines and reagents. Intellectual discussions about our research work.
Impact On going provision of reagents has enabled our publications for this grant.
Start Year 2009
 
Description International Collaboration with Vishva Dixit 
Organisation Genentech
Country United States of America 
Sector Private 
PI Contribution Use of caspase knockout mice
Collaborator Contribution Provision of caspase knockout mice
Impact No impact yet
Start Year 2013
 
Description International and national collaboration with David Underhill 
Organisation University of California, Los Angeles (UCLA)
Country United States of America 
Sector Academic/University 
PI Contribution Collaboration
Start Year 2000
 
Description International and national collaboration with Eicke Laetz 
Organisation University of Massachusetts (UMass)
Department University of Massachusetts Medical School
Country United States of America 
Sector Academic/University 
PI Contribution University of Massachusetts Medical School
Start Year 2008
 
Description International and national collaboration with Shizuo Akira, Osaka University 
Organisation Osaka University
Country Japan 
Sector Academic/University 
PI Contribution Collaboration
Start Year 1999
 
Description International and national collaborations with Kate Fitzgerald 
Organisation University of Massachusetts (UMass)
Department University of Massachusetts Medical School
Country United States of America 
Sector Academic/University 
PI Contribution Intellectual input and collaborative discussions about common research interests.
Collaborator Contribution Provision of reagents, cell lines and intellectual input to our research.
Impact Publications linked to our research grants have been facilitated by this collaboration.
Start Year 2006
 
Description International collaboration with Zoetis 
Organisation Zoetis
Country United States of America 
Sector Private 
PI Contribution Use of funds through research
Collaborator Contribution Funding
Impact No impact yet
Start Year 2013
 
Description Luke O'Neill, Trinity College, Dublin 
Organisation University of Dublin
Department Trinity College Dublin
Country Ireland, Republic of 
Sector Academic/University 
PI Contribution Collaboration with Trinity College, Dublin
Collaborator Contribution Intellectual input Collaborative discussion Transfer of new techniques
Impact Publications
Start Year 2007
 
Description Bacterial recognition by PRRs 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Participants in your research or patient groups
Results and Impact Toll2011, Garda, Italy: "Bacterial recognition by PRRs"

no actual impacts realised to date
Year(s) Of Engagement Activity 2011
 
Description Cheltenham Science Festival 2014: The Immune System: Your Inner Army 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Public engagement

No notable impacts to date
Year(s) Of Engagement Activity 2014
URL http://www.cheltenhamfestivals.com/science/whats-on/2014/the-immune-system-your-inner-army/
 
Description Co-chair Antibiotic Resistance Forum at the Cambridge Science Fair 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact I organised, spoke at and co-chaired a debate session on anti-bacterial resistance at the Cambridge Science Fair. This provoked considerable debate and discussion with members of the general public, school children and academic attendees.
Year(s) Of Engagement Activity 2015
URL https://soundcloud.com/university-of-cambridge/17-march-2015-preventing-the-rise-of-antibiotic-resis...
 
Description EMBO Innate Immunity Course South Africa: Lecturer 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact EMBO ran a course for postgraduate students and other scientists in S Africa particularly aimed at informing them about new ways to develop their research into infectious disease.
Year(s) Of Engagement Activity 2015
 
Description Hill Rd Comprehensive School: The Immune System: Your Inner Army 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact Invited talk to pupils

No notable impact to date
Year(s) Of Engagement Activity 2014
 
Description Lafferty Debate participant 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact Participated in a public debate on "Adaptive Immunity is innately redundant"
Year(s) Of Engagement Activity 2016
 
Description Poultry Vet CPD Course 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact I gave a talk about how chickens detect Salmonella, why this might contribute to its zoonotic potential and how our research may allow us to develop therapeutic strategies. This talk was given to poultry vets, poultry breeders and representatives from poultry processing companies. About 100 stakeholders attended this event in Belfast. This generated considerable discussion about preventative strategies not only for Salmonella infections but also for other food based bacterial infections.
Year(s) Of Engagement Activity 2015
 
Description Presentation on Antimicrobial Resistance to the Cambridge Enterprise network 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Industry/Business
Results and Impact I gave a presentation to a group of Cambridge Entrepreneurs about anti-microbial resistance and the challenges we faced to over come it. The talk generated a large number of questions.
Year(s) Of Engagement Activity 2015
 
Description Queens College Academic Saturday 2014: Why cats make you sneeze 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Public engagement

No notable impact yet
Year(s) Of Engagement Activity 2014
URL http://www.queens.cam.ac.uk/life-at-queens/news-and-events/academic-saturday-11th-october
 
Description Radio Cambridgeshire Interview 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Media (as a channel to the public)
Results and Impact Radio interview to explain why ARUK had given me a discipline hopping grant. My interview discussed how immunology impacts on Alzheimer's disease and how our research might help generate new therapeutic approaches to a lay audience.

None as yet
Year(s) Of Engagement Activity 2014