Exploiting novel African swine fever virus virulence factors and a porcine macrophage cell line to develop a live attenuated vaccine
Lead Research Organisation:
THE PIRBRIGHT INSTITUTE
Department Name: African Swine Fever Virus
Abstract
African swine fever (ASF) is a deadly disease of pigs and wild boar that has a very high socio-economic impact. The rapid spread of ASF in China and other Asian countries since 2018 has resulted in death or destruction of more than 7 million pigs, reducing the Chinese pig herd by about 40% and the global herd by 25%. As pork is the most widely consumed source of protein globally, this has had serious consequences on food prices and supply of protein for human consumption. Combined with continuing ASF spread in Africa and Europe, this represents an unprecedented threat to global food security. In Europe 1408 outbreaks in domestic pigs and 6003 detections in wild boars have been reported since July 2019. In S. E Asia ASF has spread to 11 countries and in Africa ASF is present in almost all countries south of the Sahara. There is no vaccine for ASF limiting disease control. A vaccine is urgently needed to limit ASF outbreaks in affected countries and prevent further global spread.
This project brings together a cutting-edge academic/industry partnership including two academic partners, The Pirbright Institute and Plymouth University and a leading international veterinary vaccine company, Zoetis, to rapidly progress vaccine development by exploiting our new research discoveries. The complexity of this large DNA virus (ASFV), which codes for up to 170 proteins, has hindered vaccine development. It is recognised that the fastest way to develop a vaccine is to produce a weakened ASFV (a live attenuated vaccine or LAV) which does not cause disease in pigs but induces an immune response that protects them from disease caused by subsequent infection with the deadly virus. We showed previously (7, BBSRC funded) that deleting ASFV genes that aren't required for the virus to replicate in cells but have important roles in helping the virus to evade the host's defences in infected animals, can produce LAV candidates. Now, we have identified novel genes, which, when deleted, can eliminate any disease signs caused by the LAV and induce good levels of protection against infection with the deadly virus. However, moderate disease signs and virus replication are observed after challenge. In this project we will improve on these results by deleting different combinations of these novel virulence factor genes to produce LAV strains causing only mild or no clinical signs following immunisation. We aim to protect 80 to 100% of pigs from disease and prevent the replication of the deadly virus so that it doesn't spread to other pigs. The lack of a cell line to grow the LAV candidates to high titres and in large volumes has prevented commercial production of this type of ASFV vaccine. Now we have developed a cell line that closely resembles the macrophage cells that ASFV naturally replicates in. Infection of this cell line produces high amounts of ASFV. In this project, the growth of this cell line will be optimized and scaled up for commercial production. The production of the selected LAV vaccine strain will also be scaled up using the cell line and pre-licensing tests of the vaccine completed. We will also use this cell line to investigate how ASFV modulates the functions of its target cell, the macrophage, thus avoiding detection and activation of the host's defences. The project will deliver high-quality science as well as providing a major step forward to commercial vaccines for ASFV.
This project brings together a cutting-edge academic/industry partnership including two academic partners, The Pirbright Institute and Plymouth University and a leading international veterinary vaccine company, Zoetis, to rapidly progress vaccine development by exploiting our new research discoveries. The complexity of this large DNA virus (ASFV), which codes for up to 170 proteins, has hindered vaccine development. It is recognised that the fastest way to develop a vaccine is to produce a weakened ASFV (a live attenuated vaccine or LAV) which does not cause disease in pigs but induces an immune response that protects them from disease caused by subsequent infection with the deadly virus. We showed previously (7, BBSRC funded) that deleting ASFV genes that aren't required for the virus to replicate in cells but have important roles in helping the virus to evade the host's defences in infected animals, can produce LAV candidates. Now, we have identified novel genes, which, when deleted, can eliminate any disease signs caused by the LAV and induce good levels of protection against infection with the deadly virus. However, moderate disease signs and virus replication are observed after challenge. In this project we will improve on these results by deleting different combinations of these novel virulence factor genes to produce LAV strains causing only mild or no clinical signs following immunisation. We aim to protect 80 to 100% of pigs from disease and prevent the replication of the deadly virus so that it doesn't spread to other pigs. The lack of a cell line to grow the LAV candidates to high titres and in large volumes has prevented commercial production of this type of ASFV vaccine. Now we have developed a cell line that closely resembles the macrophage cells that ASFV naturally replicates in. Infection of this cell line produces high amounts of ASFV. In this project, the growth of this cell line will be optimized and scaled up for commercial production. The production of the selected LAV vaccine strain will also be scaled up using the cell line and pre-licensing tests of the vaccine completed. We will also use this cell line to investigate how ASFV modulates the functions of its target cell, the macrophage, thus avoiding detection and activation of the host's defences. The project will deliver high-quality science as well as providing a major step forward to commercial vaccines for ASFV.
Technical Summary
The dramatic spread of African swine fever through Africa, Europe and Asia has resulted in the death of more than 7 million pigs in 2019 and reduced the global pig herd thus limiting pork supply and driving up prices. Live-attenuated vaccines (LAVs) produced by gene deletions are recognized to be the fastest route to vaccine development. However, the availability of a gene-deleted ASFV which meets the stringent safety criteria required for vaccine registration and the lack of a continuous cell line to scale up the production of the vaccine candidates impede the commercial development of ASFV LAVs. We will build on new developments from our team to overcome both barriers. Firstly, we have developed a porcine macrophage cell line, pMPI, that accurately represents the target cells that ASFV naturally replicates in. These cells support high levels of ASFV replication without any requirement for adaptation of virus to the cells. We will optimize the growth of pMPI cells to achieve levels compatible with large scale vaccine production and confirm that our LAV candidates do not undergo genome rearrangements during passage in these cells. Secondly, we have identified novel ASFV virulence factors, MGF 360-12L, MGF 505-1R and both EP153R and EP402R and showed that deletion of these genes in combination with others can prevent clinical signs post-immunization but still induce good levels of protection. Moderate clinical signs and virus replication are observed after challenge. We will improve these results by testing different combinations of these gene deletions by immunization and lethal challenge of pigs. This will identify optimized candidates to take forward for vaccine development. The project will deliver a pMPI master cell stock and a master seed virus of the candidate LAV produced in the cells for pre-licensing. Using these cells, high quality science will be delivered by further characterizing how ASFV evades the host's defences.
Publications
Rathakrishnan A
(2023)
A protective multiple gene-deleted African swine fever virus genotype II, Georgia 2007/1, expressing a modified non-haemadsorbing CD2v protein
in Emerging Microbes & Infections
| Description | African swine fever virus continues to spread globally causing severe socio-economic consequences in affected countries in Africa, Europe, Asia, and elsewhere. A vaccine is not yet widely available although two are under limited trials in Vietnam. In this project we aimed to develop safe and effective novel gene-deleted candidate live attenuated ASFV vaccines. We also planned to establish a novel porcine macrophage cell line for use in research and to investigate its potential for use in growing ASFV live attenuated vaccines in a commercial setting. The project brings together two strong academic partners: The Pirbright Institute and Plymouth University with expertise in ASFV and macrophage biology. The project is linked with a leading International Vaccine company. Progress on completion of objectives 1 a) Constructing and testing novel African swine fever virus gene deletion mutants by immunisation and challenge of pigs. Construction of gene-deleted or gene modified viruses From previous research we developed a strategy to construct recombinant gene-deleted or modified African swine fever viruses of the current pandemic genotype II strain Georgia 2007/1. The strategy involved replacing the wild type EP402R gene, which codes for the CD2v protein with a mutated version which abrogates the binding of red blood cells to ASFV infected cells and virus particles. The CD2v protein is known to be important for protection but the phenotype of red blood cell binding results in prolonged virus persistence in blood. Thus, by this strategy we would retain immunogenicity associated with CD2v expression but avoid the undesirable phenotype of prolonged virus persistence in blood. We had already identified single or double amino acid substitutions in the genotype I CD2v protein which abrogated binding of the protein to red blood cells (non-HAD). We made similar mutations to introduce single or double amino acid substitutions in the genotype II CD2v. Recombinant genotype II expressing mutant CD2v which was either partially haemadsorbing with a single amino acid substitution Q96R or non-haemadsorbing with a double amino acid substitution Q96R and K108D were constructed. In parallel the adjacent EP153R gene was deleted. EP153R codes for a type II transmembrane protein containing a C-type lectin domain. It has also been shown to be important for protection. In parallel with the modification of CD2v and deletion of EP153R we also deleted K145R or K145R and DP148R. These genes are at different genome loci and we previously showed deletion of K145R and DP148R together partially attenuated virulent ASFV. We also deleted additional genes from the virus. However, genes for both fluorescent protein markers that we could use to select recombinant ASFV were already incorporated in the genome of these recombinant viruses. We therefore first removed by recombination the genes for the red and green fluorescent protein markers to generate an intermediate recombinant virus not expressing either of the red or green fluorescent protein markers. We then constructed four additional viruses each with an additional single gene deleted. The additional genes deleted included B125R and A137R which code for immunogenic proteins and could provide a potential serological marker to distinguish infected from vaccinated animals (DIVA) in the field. The other viruses had deletions of H240R or I267L. Apart from the B125R gene all had previously been shown to attenuate virulent ASFV. Immunisation and challenge experiments in pigs First round: Recombinant viruses 1. GRGdeltaKE-CD2vQ96R, 2. GRGdeltaKE-CD2vQ96RK108D 3.GRGdeltaDKE-CD2vQ96RK108D 4. GRGdeltaBDKE-CD2vQ96RK108D have been tested by immunization and challenge in pigs. Virus 1 with a single mutation in CD2v, Q96R, was partially haemadsorbing and induced higher levels of viremia and clinical signs in pigs than other viruses although 100% protection was obtained in all pigs without replication of challenge virus. All the other viruses tested had the Q96R, K108D double mutation and were non-haemadsorbing. Pigs immunized with viruses 2, 3 and 4 had lower clinical signs and levels of viremia that persisted for a shorter time compared to pigs immunized with virus 1. Both viruses 2 and 3 induced high levels of protection but pigs immunized with virus 3 which had an additional deletion of DP148R gene had lower clinical and post-mortem signs post-challenge compared to those immunized with virus 2. Therefore virus 3 (GRGdeltaDKE-CD2vQ96RK108D) was taken forward for additional safety and efficacy tests as described below. The fourth virus tested 4. GRGdeltaBDKE-CD2vQ96RK108D had the B125R gene deleted and had marker genes removed from the previous virus. This was titrated by observing cytopathic effect at limiting dilution. This induced low clinical signs and viremia in most pigs and high levels of protection against challenge. However, in one experiment one pig reached the moderate severity endpoint after immunisation. Therefore, we considered this virus did not have a sufficiently good safety profile to progress. Second round: Recombinant viruses 5, 6 and 7 were produced using the non-fluorescent GRGdeltaDKE-CD2vQ96RK108D as parental virus. These had deletions of the A137R, H240R and I267L genes respectively. These deletions were expected to increase the safety of the candidate live attenuated vaccine. Pigs were immunised with viruses 5, 6, 7, and as expected, all viruses were attenuated. After challenge, all pigs immunised with virus 5, reached the moderate severity humane endpoint showing signs of acute ASFV between 3 and 4 days post-challenge. Three pigs immunised with virus 6 reached the humane endpoint by 4 days post-challenge. The other 3 pigs in this group survived until the end of the experiment. The results suggested that the deletion of the A137R or H240R genes had resulted in a strong attenuation of the parental virus such that there was insufficient replication to induce a protective immune response. In the group immunised with virus 7 (GRGdeltaI267LDKE-CD2vQ96RK108D), only one pig had a single day of high temperature at day 2 post challenge. No other clinical signs were observed, and all pigs survived until the end of the experiment. 1 b) Further testing of best candidate LAVs First round: Virus 3 (GRG?DKE-CD2vQ96RK108D) was considered to have the best combination of safety and efficacy and was taken forward for further testing. In these experiments safety was tested at 3 different doses 10E4, 10E5 and 10E6 TCID50. At these doses 0/12, 1/6 and 2/6 pigs showed mild transient clinical signs (temperature above 40.5C with some reduced eating) after immunisation. Efficacy was tested at two doses. After immunisation with 10E4, 1/6 pigs reached a moderate severity humane endpoint. All pigs survived challenge after immunisation with 10E5 TCID50. Mild to moderate clinical signs were observed in some pigs. Viremia levels were low to moderate. Early induction of antibodies and cellular responses were observed. Dissemination of virus to tissues was tested at days 7 and 14 post immunisation. Virus genome (in 13 different tissues) was either not detected or detected at low levels below 10E4 genome copies per gram tissue. Levels of 10E5 were detected in the tracheobronchial lymph node from one pig. No infectious virus was detected. Second round: 1) Minimal dose This study was done to determine the minimal dose of virus 7 (GRGdeltaI267LDKE-CD2vQ96RK108D) required to induce protection. One group of pigs was immunised with 10E3 TCID50 and another group with 10E2 TCID50. After challenge, one pig in the lower dose group was culled due to an unrelated cause, and all the others survived challenge. This indicates that immunisation with virus 7 is efficacious even when administered at low doses (10E2 TCID50). 2) Safety at high dose A group of 3 pigs was immunised with a high dose (10E5 TCID50) and culled at day post immunisation (dpi) 14 to evaluate macroscopic lesions caused by the vaccination. One pig had a temperature of 41C at day 7 post immunisation but no other clinical signs in this pig or the other two pigs were observed. At the post-mortems, two pigs had scores below 3 and one pig had a score of 7 (mainly due to lymph nodes' enlargement). Viral genome was detected in the blood of one of the pigs but below the limit for accurate quantification. 3) Reversion to virulence (pig passaging) Passaging of the virus 7 (GRGdeltaI267LDKE-CD2vQ96RK108D) in pigs was carried out to determine the stability of the virus and the risk of reversion to virulence if transmission occurred. Guidelines from a draft WOAH document and VCIH guidelines were followed. In the passaging experiments we aimed to combine blood or tissue samples from at least two pigs collected at a peak time of viremia. In the first passage the pigs were immunised with 10E4 TCID50. Blood samples collected from these pigs were titrated and a mixture of blood samples from 3 pigs at the peak of viremia was inoculated into other 6 pigs. Back titration of the inoculum showed it had a titre of 10E5 TCID50. Two pigs in the second passage group showed increases in temperature above 40.6C, one on dpi 7 and the other dpi 9. Virus genome copies per ml in blood and tissues were determined and combined to prepare the inoculum for the third pig passage. The dose given to each of 6 pigs in this passage was 10E4 TCID50. Five pigs showed a temperature above 40.6C following inoculation. Additionally, one of the pigs showed temperatures above 40.6C for four consecutive days and was culled at the moderate humane end point. Virus genome copy numbers in blood reached up to 10E6.12 /ml of blood. These bloods were combined, diluted and administered to 6 pigs in a fourth passage. The dose given was 8.54x10E3 TCID50. One pig had a temperature above 40.6C for 4 days which was dropping when the pig was culled. Another pig showed a temperature of 40.6C for one day and the remaining pigs showed no clinical signs. Virus genome copy numbers in blood reached up to 10E5.7/ml of blood. Samples collected during the passages will be used for whole genome sequencing, in order to identify any viral genome changes that may have occurred. 2 a) Optimising growth of the pMPI/PLTA58 cells and ASFV yield Macrophage and mesenchymal cells were observed to differentiate from foetal pig spleen suspensions in culture. The macrophage-like cells could be maintained in co-cultures with the mesenchymal feeder cells but replication rates were slow. Therefore, a new strategy was developed to conditionally transform the macrophage-like cells using a temperature sensitive large T antigen delivered using a lentivirus vector. Using this strategy an immortalised macrophage-like cell line, PLTA58, was obtained which replicates at 33C but shows reduced or no replication at 37C as the large T antigen is inactivated at this temperature. Culture conditions were optimised and PLTA58 cells were observed to grow robustly and continuously at 33C. Similar growth rates were observed either in the presence or absence of GMCSF. The cells attach to the surface of tissue culture flasks but detach during culture and can be harvested by harvesting the supernatant. When transferred to 37C, amounts of SV40 large T decreased dramatically by 4 days after transfer and the protein was detected in the cytoplasm where it is inactive rather than an active nuclear form. Infections of PLTA58 cells with ASFV isolates from different genotypes and with a vaccine prototype described above confirmed that PLTA58 cells were equally susceptible to infection as primary porcine macrophages. Similar levels of infection and rates and titres of replication were observed. Cells infected with wild type viruses also showed the same characteristic red blood cell rosettes around infected cells (hemadsorption). PLTA58 cells remained fully susceptible to ASFV infection for a period of at least 10 days after moving to 37C. The results confirm that the PLTA58 cells are a suitable cell line for research, diagnosis and potentially for growth of live attenuated vaccines. 2 b) Characterisation of PLTA58 phenotype To confirm that the PLTA58 cells retain a macrophage like phenotype, a number of assays were carried out. These assays included a demonstration that the PLTA58 cells are strongly phagocytic and express markers typical of porcine alveolar macrophages including CD163, CD169, CD172a and CD203a. The proteome signature of the PLTA58 cells was compared at 37C and 33C to identify proteins either up or down regulated in expression when large T antigen was downregulated. Functions of 719 proteins identified in both conditions were compared by gene ontology enrichment analysis revealing GO terms predominantly targeted by large T antigen. Hierarchical clustering analysis showed a distinct separation between PLTA58 cells grown at 33 and 37C. To assess innate immune responses of PLTA58 and primary pig alveolar macrophages (PAMs) to ASFV infection we quantified the cytokines released after infection with isolates OURT88/1 (genotype I) and Georgia 2007/1 (genotype II). Anti-inflammatory cytokine IL-10 was only detected at very late timepoints of 48h, with significantly higher levels in PLTA58 than PAMs. The pro-inflammatory cytokines showed an opposite trend, with higher levels in PAMs infections than PLTA58. The increased release of pro-inflammatory cytokines in PAMs can be related to a more activated state of these cells or different differentiation profiles. 3 a) Scale up of the PLTA58 cells and optimise conditions for growth of ASFV LAVs in a commercial setting. The PLTA58 cells were supplied to our industrial partner Zoetis in Autumn 2023 in order to establish culture conditions in their commercial facilities. Upon arrival to Zoetis, cells were tested for the presence of Mycoplasma and pestivirus and they were free of these contaminants. In order to prepare a PLTA58 cell stock, subcultures were done progressively. PLTA58 cells were grown in RPMI containing 10 mM HEPES and 10% FBS at 33C. From the original stock, two vials of PLTA58 cells were thawed in 75 cm2 tissue culture flask. The cells took 2-3 weeks to achieve confluence; when full confluence was achieved, subcultures could be done once per week. After reaching the feeder layer confluency, cells were expanded in several 75 cm2 tissue culture flasks. From 75 cm2 tissue culture flasks cells were expanded to 150 cm2 tissue culture flasks and from 150 cm2 to 300 cm2 tissue culture flasks. Currently the cells are being cultured in 10-stack culture chambers (6360 cm2) in a final volume of 1500ml. The maximum cell concentration obtained in all the flasks was around 1x 10E6 cells/mL and the cell viability was higher than 98%. 3b) Establish master seed stock of PLTA58 cells and pre-licensing stock of selected ASFV LAV. Master seed stocks were established at passage 5 (19 vials, ref. 110324) and passage 11 (138 vials, ref. 280624) 4. To investigate the roles of MGF360-12L, MGF505-1R, EP153R in ASFV infected macrophages Research on this objective has mainly focused on the EP153R and CD2v proteins since these are deleted or modified in the vaccine candidates described in 1a and 1b. To determine the localisation of these proteins in virus infected cells, recombinant ASFV has been constructed expressing N and C-terminally tagged versions of the EP153R and EP402R genes. Domains in the EP402R protein that are required for interaction with red blood cells have been mapped. Potential interactions between these proteins are also being investigated by fusion with split fragments of a green fluorescent protein gene. Preliminary data indicates that they do not interact with each other in transfected cells. The growth of the ASFV deletion mutants GRGdeltaMGF360-12L and GRGdeltaMGF505-1R was characterised in vitro. The GRGdeltaMGF360-12L virus showed a growth defect when compared to the wild-type virus in pig primary macrophages. This growth defect was not reverted by pre-treatment of cells with Ruxolitinib, a Janus kinase inhibitor that impairs cellular responses to interferon. This indicates that the observed growth defect is not related to the inability of this virus to control interferon responses. In contrast, in PLTA58 cells the GRGMGF360-12L grew to similar titres as the wild -type virus. This may be associated with the activation state of these cells or different differentiation profiles as described in objective 2b. |
| Exploitation Route | The gene-deleted live attenuated African swine fever virus vaccine candidates may be taken forward for commercial development by a Veterinary Vaccine Company. The porcine macrophage cell line PLTA58 can replace the use of primary porcine macrophages for research and diagnosis. It may also be useful for production of Live Attenuated ASFV vaccines and for research and diagnosis of other pig viruses including PRRSV (Porcine Respiratory and Reproductive Syndrome Virus). |
| Sectors | Agriculture Food and Drink Pharmaceuticals and Medical Biotechnology |
| Description | The porcine macrophage cell line PLTA58 has been shown to support replication of several African swine fever virus (ASFV) isolates from different genotypes and can be used to replace the use of primary porcine macrophages for research and diagnosis. A candidate live attenuated vaccine for ASF was found to be effective and it is now undergoing the reversion to virulence tests necessary for further commercial development. |
| First Year Of Impact | 2024 |
| Sector | Agriculture, Food and Drink |
| Impact Types | Economic |
| Description | A human receptor screening resource for host-pathogen interactions |
| Amount | £547,787 (GBP) |
| Funding ID | MR/X019705/1 |
| Organisation | Medical Research Council (MRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 08/2023 |
| End | 08/2026 |
| Description | Developing a complex in vitro airway model to study respiratory viral pathogenesis, lung macrophage function and herpes viral vaccine vectors in pigs BBSRC/NC3Rs NC/X002446/1 |
| Amount | £249,908 (GBP) |
| Organisation | The Pirbright Institute |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 01/2023 |
| Description | Predicting cross-protection of African swine fever virus (ASFV) vaccines against diverse genotypes circulating in Africa |
| Amount | £40,238 (GBP) |
| Funding ID | IAA2182 |
| Organisation | Medical Research Council (MRC) |
| Sector | Public |
| Country | United Kingdom |
| Start | 02/2024 |
| End | 01/2025 |
| Title | Fluorescence activated single cell sorting to isolate gene-deleted/modified African swine fever virus |
| Description | A method was developed to use fluoresecence activated single cell sorting to isolate recombinant gene-deleted ASFV using insertion of fluorescence protein genes under control of African swine fever virus promoters as reporter to isolate cells infected with recombinant viruses. This method was used to generate 15 different single and multiple gene-deleted ASFV and study the impact of the gene deletions on virus replication and host responses and develop candidate live attenuated vaccines. This method has been further refined by splitting the fluorescent protein gene such that two genes can be deleted at the same time. |
| Type Of Material | Technology assay or reagent |
| Year Produced | 2021 |
| Provided To Others? | Yes |
| Impact | Development of candidate gene-deleted live attenuated African swine fever virus vaccines |
| URL | https://doi.org/10.3390/v12060615 |
| Title | Porcine macrophage cell line for research on African swine fever virus |
| Description | A transformed porcine macrophage cell line derived from foetal tissue that supports replication of African swine fever virus and other porcine viruses. This can reduce the use of primary porcine macrophages from pigs for virus growth, titration, diagnosis and research. |
| Type Of Material | Cell line |
| Year Produced | 2022 |
| Provided To Others? | No |
| Impact | Reduced use of primary porcine macrophages from pigs |
| Description | BBSRC LINK Project |
| Organisation | University of Plymouth |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | Confirm susceptibility of porcine macrophage cell line to African swine fever virus |
| Collaborator Contribution | Provide a conditionally transformed porcine macrophage cell line for research and diagnosis of African swine fever virus |
| Impact | None yet |
| Start Year | 2019 |
| Description | Exploiting novel porcine macrophage cell lines and ASFV virulence factors |
| Organisation | University of Plymouth |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | My team has developed gene-deleted African swine fever viruses in order to study the role of these virus genes in virus replication and modulation of host responses. These gene-deleted viruses are also being evaluated as candidate live attenuated vaccines. |
| Collaborator Contribution | University of Plymouth provided novel porcine macrophage cell lines to evaluate their susceptibility to African swine fever virus (ASFV) replication and as tools for ASFV research, vaccine development and diagnosis. These cell lines are being further characterized and developed by our partners at University of Plymouth. |
| Impact | Multi-disciplinary: Virology, Immunology, Cell biology, Vaccinology |
| Start Year | 2019 |
| Description | Exploiting novel porcine macrophage cell lines and ASFV virulence factors |
| Organisation | Zoetis |
| Country | United States |
| Sector | Private |
| PI Contribution | The Pirbright Research Team is constructing gene deleted African swine fever viruses and is testing these in pig macrophage primary cell cultures and using novel pig macrophage cell lines from University of Plymouth. These are also being tested in pigs in immunization and challenge vaccination experiments. |
| Collaborator Contribution | Zoetis will establish conditions for scaling up of the novel pig macrophage cell lines in a commercial setting. |
| Impact | Multi-disciplinary: Virology, cell biology, pathogenesis, immunology, vaccinology |
| Start Year | 2015 |
| Title | VACCINE AGAINST AFRICAN SWINE FEVER VIRUS INFECTION |
| Description | The present invention relates to attenuated African Swine Fever viruses. The attenuated viruses protect pigs against subsequent challenge with virulent virus. The present invention also relates to the use of such attenuated viruses to treat and/or prevent African Swine Fever. The invention also relates to EP402R proteins of African Swine Fever virus comprising particular amino acid substitutions, as well as polynucleotides encoding such proteins and African Swine Fever viruses comprising such proteins. |
| IP Reference | WO2021176236 |
| Protection | Patent application published |
| Year Protection Granted | 2021 |
| Licensed | No |
| Impact | The gene-deleted African swine fever viruses are being taken forward as candidate live attenuated vaccines and included in a BBSRC LINK award |
| Description | EPIZONE 16th Annual Meeting 2024, Sweden. Presentation by Anusyah Rathakrishnan: Cross-protection induced by genotype II modified live African swine fever virus candidate vaccine(s) against genotype I but not against genotype IX. |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | The presentation led to discussions with other researchers in the field. |
| Year(s) Of Engagement Activity | 2024 |
| Description | Invited Presentation to Pig Veterinary Society Birmingham UK October 2022 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Presentation |
| Year(s) Of Engagement Activity | 2022 |
| Description | Invited Seminar China Agricultural University Beijing September 2023 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Seminar at China Agricultural University Veterinary Faculty on "African swine fever virus evasion of host defences and vaccine development". Discussion with faculty and postgraduate students. |
| Year(s) Of Engagement Activity | 2023 |
| Description | Keynote Presentation European Society for Veterinary Virology Ghent Belgium Sep 2022 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Other audiences |
| Results and Impact | More than 500 people attended an International Conference on Veterinary Virology |
| Year(s) Of Engagement Activity | 2022 |
| URL | https://esvv2022.ugent.be/ |
| Description | Keynote Presentations at International Workshop on African swine fever virus Beijing September 2023 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | The International Workshop on African swine fever virus was organised by the US/China Animal health Network and attended by ~50 people comprising leading International experts, policy makers, postgraduate students and experts from industry. The aim was to review current knowledge on ASFV and identify areas for future research. A report on the meeting and outcomes was published in Viruses. It is expected that future meetings will be organised. |
| Year(s) Of Engagement Activity | 2023 |
| Description | Keynote presentation at the Swedish Virology Society Annual Meeting |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | About 100 people from Swedish Society of Virology attended my keynote talk at their annual meeting |
| Year(s) Of Engagement Activity | 2021 |
| Description | Microbiology Society Annual Conference 2024, Presentation by Anusyah Rathakrishnan: A protective multiple gene-deleted African swine fever virus genotype II, Georgia 2007/1, expressing a modified non-haemadsorbing CD2v protein |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Postgraduate students |
| Results and Impact | The presentation led to discussions with other researchers in the field. |
| Year(s) Of Engagement Activity | 2024 |
| Description | Poster Presentation British Society for Immunology |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Poster presentation by Justyna Lopatecka at BSI meeting December 2023 Belfast. Unveiling a novel continuous macrophage model: conditionally immortalized porcine embryonic spleen and GM-CSF derived macrophages, PLTA58 cells |
| Year(s) Of Engagement Activity | 2023 |
| Description | Presentation and panel discussion: Symposium "African Swine Fever Virus: An Emerging Global Challenge", held at Faculty of Veterinary Medicine, University of Lisbon, Portugal |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | The presentations led to further discussions on the feasibility and safety of the use of live attenuated vaccines against African swine fever in different countries and epidemiological scenarios. |
| Year(s) Of Engagement Activity | 2024 |
| Description | Presentation at Microbiology Society Meeting |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Two presentations at Microbiology Society UK Annual Meeting Belfast April 2022 |
| Year(s) Of Engagement Activity | 2022 |
| Description | Presentation by Dr Ana Reis 16th Applied Biosafety Meeting, Swiss Biosafety Network Geneva 25th to 26th August 2022 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | Talk on Reserach on African swine fever |
| Year(s) Of Engagement Activity | 2022 |
| Description | Presentation by Dr Anusyah Rathakrishnan at European Society for Veterinary Virology Conference Ghent Sep 2022 |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Research presentation on development of live attenuated ASFV vaccine |
| Year(s) Of Engagement Activity | 2022 |
| Description | Presentation: "Identification and characterization of non-essential ASFV genes for the rational design of live attenuated vaccines" to visiting scientists from the Chinese Academy of Agricultural Sciences |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | The presentation led to further discussions on the use of live attenuated vaccines to control ASF. |
| Year(s) Of Engagement Activity | 2024 |
| Description | Presentations to Veterinary Staff Northern Ireland Department of Agriculture, Environment and Rural Affairs |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | Presentations to Northern Ireland Veterinary Staff on African swine fever to explain risks, transmission routes diagnosis and vaccine development. |
| Year(s) Of Engagement Activity | 2023 |
| Description | Research Presentation Veterinary Research Club UK "An African Swine Fever vaccine candidate based on multiple targeted gene deletions and mutagenesis" |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | Talk on African swine fever virus vaccine development |
| Year(s) Of Engagement Activity | 2022 |
| Description | TV Interview Deutsche Welt |
| Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Other audiences |
| Results and Impact | Interview and filming at Pirbright for a programme on African swine fever virus broadcast on Deutsche Welt German TV Channel |
| Year(s) Of Engagement Activity | 2022 |