Host resistance mechanisms to bovine respiratory syncytial virus (BRSV), African swine fever virus (ASFV) and Bluetongue virus (BTV)

Lead Research Organisation: The Pirbright Institute
Department Name: UNLISTED

Abstract

The aim of this project is to advance understanding of the mechanisms of immunity to and the pathogenesis of African swine fever virus (ASFV), bluetongue virus (BTV) and bovine respiratory syncytial virus (BRSV). The knowledge gained will contribute to the development of new or improved vaccines. Developments in DNA technology have created new opportunities for vaccine production, both through genetic manipulation of pathogens and by enabling the identification of defined antigens that induce protective immune responses. These opportunities, together with a detailed understanding of the components of the immune response that mediate protection or which contribute to the pathogenesis of disease, and knowledge of how these responses can be induced and regulated at an appropriate location in vivo, will provide a conceptual framework for the rational development of new or improved vaccines against BRSV, ASFV and BTV.

Publications

10 25 50

 
Description In humans and mice, ?d T cells represent approximately 5% of the total circulating lymphocytes. In contrast, the ?d T cell compartment in ruminants accounts for 15-60% of the total circulating mononuclear lymphocytes. Despite the existence of CD4(+)CD25(high) Foxp3(+) T cells in the bovine system, these are neither anergic nor suppressive. We have demonstrated that bovine ?d T cells are the major regulatory T cell subset in peripheral blood. These ?d T cells spontaneously secrete IL-10 and proliferate in response to IL-10, TGF-ß, and contact with antigen-presenting cells (APC). IL-10-expressing ?d T cells inhibit antigen-specific and nonspecific proliferation of CD4(+) and CD8(+) T cells in vitro. APC subsets expressing IL-10 and TFG-ß regulate proliferation of ?d T cells producing IL-10. ?d T cells appear to be a major regulatory T cell population in the bovine system.

Bovine respiratory syncytial virus (BRSV) causes inflammation and obstruction of the small airways, leading to severe respiratory disease in young calves. The virus is closely related to human (H)RSV, a major cause of bronchiolitis and pneumonia in young children. The ability to manipulate the genome of RSV has provided opportunities for the development of stable, live attenuated RSV vaccines. The role of the SH protein in the pathogenesis of BRSV was evaluated in vitro and in vivo using a recombinant (r)BRSV in which the SH gene had been deleted. Infection of bovine epithelial cells and monocytes with rBRSV?SH, in vitro, resulted in an increase in apoptosis, and higher levels of pro-inflammatory cytokines compared with cells infected with parental, wild-type (WT) rBRSV. Although replication of rBRSV?SH and WT rBRSV, in vitro, were similar, the replication of rBRSV?SH was moderately reduced in the lower, but not the upper, respiratory tract of experimentally infected calves. Despite the greater ability of rBRSV?SH to induce pro-inflammatory cytokines, in vitro, the pulmonary inflammatory response in rBRSV?SH-infected calves was significantly reduced compared with that in calves inoculated with WT rBRSV, 6 days previously. Virus lacking SH appeared to be as immunogenic and effective in inducing resistance to virulent virus challenge, 6 months later, as the parental rBRSV. Furthermore, intranasal vaccination of calves with maternally-derived antibodies induced protection against viruelnt virus challenge.These findings suggest that rBRSV?SH may be an ideal live attenuated virus vaccine candidate, combining safety with a high level of immunogenicity.

The immunogenicity and protective efficacy of a virus-vectored human RSV vaccine was evaluated against BRSV in calves and a heterologous prime/boost regimen was shown to give sterile immunity against BRSV.

Bovine plasmacytoid dendritic cells produce high levels of IFN, some of which is acid labile, when exposed to live, but not UV-inactivated, BTV. The response is enhanced when BTV is complexed with BTV-specific antibodies. Different serotypes of BTV differ in their ability to induce IFN

In contrast to the well-described, CAR-dependent mechanism of adenovirus attachment and penetration of permissive cells, we demonstrated that adenovirus enters skin-draining dendritic cells via actin-dependent endocytosis

African swine fever virus (ASFV) inhibits autophagy at early times post infection. This has implications for induction of adaptive immune responses. ASFV ORFs recognised by ASFV-immune lymphocytes from cc, dd and bb pigs have been identified and cloned into replication-defective adenovirus vectors for development of ASFV vaccine candidates. Vaccination of a small number of pigs with a pool of adenovirus-vectored vaccines induced protection against severe disease and reduced viraemia in 50% of the pigs. A number of tagged ASF viruses have been generated that encode a fluorescent-virus structural fusion protein in the place of a non-essential gene. These will be of value in studying the pathogensis of ASFV in pigs and ticks.
A prefusion form of the BRSV F protein induced higher levels of neutralising antibodies and a greater level of protection against BRSV infection than the postfusion form of the F protein. Further studies have demonstrated that protection against BRSV in calves with maternally-derived serum antibodies can be induced by intramuscular injection of the prefusion form of the bRSV F protein.
Exploitation Route A grant has been submitted to further develop rBRSVdelta SH as a vaccine for calf respiratory disease. A PhD student will investigate the effect of ASFV on autophagy further.
A grant has been submitted to extend studies on bovine gamma/delta T cells and determine their role in combatting virus infection.
A Bill & Melinda Gates grant was awarded to determine the minimum protective dose of the Ad-vectored PPR vaccine in African goats.
Clinical trials of the virus-vectored RSV vaccine have been undertaken in man.
The prefusion form of the BRSV F protein could be developed as a vaccine
Sectors Agriculture, Food and Drink,Healthcare

 
Description African swine fever is a devastating disease of pigs which has spread to the borders of the EU in recent years. We have identified antigens that are recognised by ASFV immune lymphocytes and these have been expressed in replication defective adenovirus vectors and will be evaluated as potential vaccine candidates. A patent application for ths novel ASFV vaccine is being prepared. An Adenovirus-vectored vaccine expressing the surface glycoproteins of peste des petits ruminants virus (PPRV) has been developed and was shown to induce complete protection against PPR challenge, 3 months after a single intramuscular dose of vaccine. This vaccine has the potential to distinguish vaccinated from infected animals and would be of value in the end stages of a PPR eradication campaign. An adenovirus-vectored and MVA-vectored RSV vaccine for use in man against human RSV has been developed and was shown to be effective against the closely related BRSV in calves. this vaccine is now in clinical trials in man. A prefusion form of the BRSV F protein has ben shown to elicit higher tires of neutralising antibodies and greater protection against BRSV infection than the post-fusion BRSV
First Year Of Impact 2016
Sector Agriculture, Food and Drink,Healthcare
Impact Types Societal,Economic

 
Description DEFRA Expert elicitation on CSF and ASF
Geographic Reach National 
Policy Influence Type Participation in a advisory committee
 
Description Grand Challenges Explorations
Amount $100,000 (USD)
Funding ID OPP1098823 
Organisation Bill and Melinda Gates Foundation 
Sector Charity/Non Profit
Country United States
Start 01/2014 
End 04/2015
 
Description Horizon 2020
Amount € 239,067 (EUR)
Funding ID 633184 
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 03/2015 
End 02/2019
 
Description SFS-10-2017 - Research and approaches for emerging diseases and pests in plants and terrestrial livestock: Addressing the dual emerging threats of African Swine Fever and Lumpy Skin Disease in Europe (DEFEND)
Amount € 5,986,250 (EUR)
Funding ID 773701 
Organisation European Commission H2020 
Sector Public
Country Belgium
Start 06/2018 
End 05/2023
 
Description Studentship: Autophagy and African swine fever virus
Amount £21,909 (GBP)
Funding ID BBS/E/I/00002120 
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 10/2015 
End 09/2019
 
Description BRSV prefusion F 
Organisation HUMABs Biomed, Bellinzona,Switzerland
Country Switzerland 
Sector Private 
PI Contribution Evaluation of the immunogenicity and protective efficacy of different forms of the bovine respiratory syncytial virus F protein in calves.
Collaborator Contribution Production of purified BRSV F proteins
Impact None yet
Start Year 2015
 
Description BRSV prefusion F 
Organisation National Institutes of Health (NIH)
Department Vaccine Research Center (VRC)
Country United States 
Sector Public 
PI Contribution Evaluation of the immunogenicity and protective efficacy of different forms of the bovine respiratory syncytial virus F protein in calves.
Collaborator Contribution Production of purified BRSV F proteins
Impact None yet
Start Year 2015
 
Description EMIDA 
Organisation French National Institute of Agricultural Research
Department INRA Versailles
Country France 
Sector Public 
PI Contribution The establishment of a standardised experimental BRSV calf model and the wide exchange of sampling and laboratory techniques. The immunogenicity and protective efficacy of a live recombinant bRSV lacking the SH gene, which we had previously shown to be attenuated and induce protective immunity in bRSV-seronegative calves was compared with two subunit vaccines supplied by collaborators, in calves with maternally-derived antibodies. The 3 vaccine candidates had DIVA potential, and calves were challenged 3 months after vaccination.. The SH protein was identified as potential DIVA protein, after screening of antibodies specific for several candidate proteins in naturally infected animals.
Collaborator Contribution Collaborators developed and supplied bRSV subunit vaccine candidates and undertook initial evaluation in calves with maternally-derived bRSV-specific antibodies, who were challenged with bRSV 5 weeks after initial vaccination. DIVA assays were set up based on artificially produced peptides and proteins.
Impact Publications: 10.1371/journal.pone.0100392; 10.1128/CVI.00162-14; 10.1186/s12917-015-0389-6; 10.1371/journal.pone.0186594. Multidiscipinary: Immunology, virology, veterinary, biochemical, proteomics, bio-informatics Further funding: Horizon 2020
Start Year 2011
 
Description EMIDA 
Organisation Swedish University of Agricultural Sciences
Country Sweden 
Sector Academic/University 
PI Contribution The establishment of a standardised experimental BRSV calf model and the wide exchange of sampling and laboratory techniques. The immunogenicity and protective efficacy of a live recombinant bRSV lacking the SH gene, which we had previously shown to be attenuated and induce protective immunity in bRSV-seronegative calves was compared with two subunit vaccines supplied by collaborators, in calves with maternally-derived antibodies. The 3 vaccine candidates had DIVA potential, and calves were challenged 3 months after vaccination.. The SH protein was identified as potential DIVA protein, after screening of antibodies specific for several candidate proteins in naturally infected animals.
Collaborator Contribution Collaborators developed and supplied bRSV subunit vaccine candidates and undertook initial evaluation in calves with maternally-derived bRSV-specific antibodies, who were challenged with bRSV 5 weeks after initial vaccination. DIVA assays were set up based on artificially produced peptides and proteins.
Impact Publications: 10.1371/journal.pone.0100392; 10.1128/CVI.00162-14; 10.1186/s12917-015-0389-6; 10.1371/journal.pone.0186594. Multidiscipinary: Immunology, virology, veterinary, biochemical, proteomics, bio-informatics Further funding: Horizon 2020
Start Year 2011
 
Description Interferon stimulated genes 
Organisation Royal Veterinary College (RVC)
Country United Kingdom 
Sector Academic/University 
PI Contribution Hosted meetings and carried out preliminary experiments
Collaborator Contribution Contributed reagents and expertise
Impact Preliminary data was used to support an MSc project. This has since led to a publication and a PhD project.
Start Year 2016
 
Description Prefusion HRSV F 
Organisation Institute of Health Carlos III
Country Spain 
Sector Public 
PI Contribution Evaluation of the immunogenicity and protective efficacy of the different forms of the human respiratory syncytial virus F protein in mice.
Collaborator Contribution Provision of purified proteins for vaccination & analysis of serum antibody responses
Impact A manuscript has been published
Start Year 2015
 
Description Swine haplotyping 
Organisation Gift Of Life
PI Contribution Prepared and shipped samples
Collaborator Contribution Sample analysis
Impact Data generation. Not multi-disciplinary
Start Year 2016
 
Title RSV vaccine 
Description Pre-clinical studies have demonstrated efficacy in small animal models of RSV infection and against bovine RSV infection in calves, a natural host of BRSV. These studies demonstrated that the vaccine was safe and effective in calves without any enhancement of respiratory disease. As a result of this, the vaccine has now undergone phase I clinical trials in Oxford, funded by Okairos and GSK and was shown to be safe and immunogenic (http://bmjopen.bmj.com/content/5/10/e008748.full). 
Type Therapeutic Intervention - Vaccines
Current Stage Of Development Early clinical assessment
Year Development Stage Completed 2014
Development Status Under active development/distribution
Clinical Trial? Yes
UKCRN/ISCTN Identifier 35082/0003/001-0001
Impact None yet 
 
Description Advances for an RSV vaccine 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Media (as a channel to the public)
Results and Impact Interview with a reporter from a Surrey radio station about recent advances in the development of a vaccine to protect against RSV in babies following publication of a paper (http://stm.sciencemag.org/content/7/300/300ra127.short), which was broadcast the next day.
Year(s) Of Engagement Activity 2015
URL http://stm.sciencemag.org/content/7/300/300ra127.short
 
Description Babraham Institute Ethics event 
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 Approximately 50 school children attended the event at the Babraham institute to learn about the use of animals in research and the three Rs - Refinement, Reduction and Replacement - which govern such use. They heard about breakthroughs in medicine and healthcare treatments that have only been possible through doing research with animals, about the work of The Pirbright Institute in the development of vaccines and control strategies to prevent viral diseases in livestock and transmission of viruses from animals to humans, and about research that is currently being carried out by the Babraham Institute into Alzheimer's disease. The workshop broadened the pupils' knowledge of biomedical research and its applications and encouraged them to think about the wider social and ethical implications of scientific discoveries they hear about in the news and other media.
Year(s) Of Engagement Activity 2015
URL http://babraham.ac.uk/get-involved/secondary-schools/ethics-workshops
 
Description Oxford Human & Veterinary Vaccinology course 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Type Of Presentation Paper Presentation
Geographic Reach International
Primary Audience Industry/Business
Results and Impact 30 people (post-graduate students, scientsits from academia and industry) attended. Presentations and workshops sparked questions and discussion.

Not known
Year(s) Of Engagement Activity 2012,2013,2014,2015
URL https://www.conted.ox.ac.uk/courses/C900-1
 
Description Pig and Poultry Fair 2019 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Discussed Institute research with pig and poultry farmers, related industry and the general public. Received requests for more information related to research, business and studentships.
Year(s) Of Engagement Activity 2018
URL https://www.pigandpoultry.org.uk/
 
Description Presentation to U3A 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Presented an overview of African swine fever virus to members of the University of the Third Age, which sparked plenty of questions and interesting debate.
Year(s) Of Engagement Activity 2017
 
Description Talk as part of the University of Veterinary Medicine (Vienna) doctoral school "Infectious Diseases of Pig and Poultry" 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact Talked about the Pirbright Institute's work on African swine fever virus to researches in Veterinary Medicine (Virology and Immunology) in Vienna.
Year(s) Of Engagement Activity 2018
 
Description University MSc course 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact Approximately 10 MSc students at Surrey University each year, which sparked discussion and questions
Year(s) Of Engagement Activity 2013,2014,2015,2016,2017
 
Description Vaccinology in Africa course 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Type Of Presentation Paper Presentation
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact 30 scientists from Africa working in the Vaccinology field attended. The presentations and workshops sparked questions and a lot of discussion.

There were requests to repeat the course in other regions in Africa
Year(s) Of Engagement Activity 2013,2014