Veterinary immunology is a vital and growing area of research, and as such we recently expanded the scope of our journal Discovery Immunology to include this fascinating field. In this article we hear about some of the recent developments in this area from The Pirbright Institute, whose scientists will join members of the BSI Comparative and Veterinary Immunology Group (CVIG) to share their expertise at the BSI Congress in December.
Almost five years since COVID-19 was declared a global pandemic, the world continues to grapple with its lasting impact on public health. While the pandemic catalysed huge scientific advances, it was also was a stark reminder of how interconnected human and animal health really is.
Many of the most devastating viral diseases, such as influenza, COVID-19, SARS and Ebola, originated in animals before making the leap to humans. Although there are risks posed by zoonotic diseases, animals can also be key allies in the fight against infectious diseases.
Scientists at The Pirbright Institute are increasingly making use of livestock – in particular, pigs, as a useful model for studying human respiratory viruses and immune responses. Unlike traditional small-animal models, pigs share many physiological, anatomical and genetic similarities to humans, making them ideal for studying immunity, testing vaccines and therapeutics.
By looking beyond the lab mouse and towards large animal models, researchers at Pirbright are bridging the gap between veterinary and human immunology. Aided by 30 years of investment in infrastructure and scientific expertise through UKRI’s Biotechnology and Biological Sciences Research Council, the Institute is transforming the way we approach disease prevention and treatment.
Pigs and respiratory viruses
Respiratory viruses, such as influenza and coronaviruses, are among the greatest threats to global health. Studying these viruses in their natural animal hosts provides vital insights into their evolution, immune responses and potential cross-species transmission. Pigs are a natural host for porcine respiratory coronavirus (PRCV), a virus that has many similarities to human coronaviruses. Being able to understand the biology of the virus and the mechanisms that lead to mild or severe disease in pigs is crucial for developing new vaccines for emerging and severe coronavirus diseases in both livestock and humans.
Pigs are also frequently involved in the zoonotic transmission of other viruses, such as influenza, acting as a ‘mixing vessel’ for different strains. Developing effective vaccines against influenza, for both humans and livestock, relies on triggering immune cells and antibodies that are ‘just about right’. Pirbright researchers and collaborators at the Babraham Institute have created a ‘pig lung atlas’, providing a detailed map of immune cells in the lung before and after influenza infection or immunisation.1
Differences in the balance between cells that combat infection or control inflammation have revealed why some vaccines fail despite triggering strong immune responses. “Mapping the pig lung has given us a new perspective on how respiratory viruses interact with the immune system. This knowledge is key to designing vaccines that provide stronger, longer-lasting protection,” says Professor Elma Tchilian, Mucosal Immunology Group Lead at Pirbright.
Improving our understanding of local immunity in the lungs paves the way for better-designed vaccines against influenza, coronaviruses and other respiratory pathogens.
Immunological reasoning
The next generation of vaccines and therapies will need to be more adaptable, durable and capable of providing broad protection across multiple strains of evolving viruses. One major initiative helping to drive this progress is the Immunological Toolbox at Pirbright, a global resource developed to advance veterinary immunology. The resource is a collection of over 500 hybridomas that produce monoclonal antibodies (mAbs) against cattle, pig and chicken cell surface markers or viral proteins. Widely used in laboratories worldwide, the toolbox provides several antibodies that are fundamental to assessing immune responses.
A major project is now underway to sequence all hybridomas held in its database stocks, as well as those held at The Roslin Institute and other collaborating institutes in Europe and North America. Converting these sequences into transfectable gene blocks ensures their long-term availability while also reducing the cost of cryostorage. “By making these antibodies and resources more accessible, we’re enabling information exchange and collaboration, promoting veterinary immunology research where outputs can support human health,” said Professor John Hammond, Director of Research and Immunogenetics group lead at The Pirbright Institute.
This initiative opens the possibility of engineering antibodies to better suit research needs and, with The Roslin Institute, will generate new antibodies that can be sequenced and added to the collection. As more researchers, veterinarians and clinicians engage with the resource and use the most informative animal models, our understanding of both veterinary and human immunology will ultimately be improved.
Natural born killers
Developing more effective vaccines against infectious diseases requires an understanding of the genes involved in initiating and controlling the immune response. Pirbright’s Immunogenetics Group studies these genes in livestock species, which can be diverse and variable between individual animals. Examining how genetic diversity influences the immune system has great potential to improve disease resistance.
One valuable model for this research is the inbred Babraham pig which has a highly homozygous genetic background, including in the major histocompatibility complex (MHC) loci. Its genetic uniformity makes it a powerful tool for immunological research. A recent genome assembly and transcriptome atlas2 of the Babraham pig has revealed key details about immune-related gene complexes, enhancing the animal’s potential use as a biomedical model for better human and animal health.
Characterising natural killer cell receptors and MHC class I molecules is a great step towards better understanding how animals are responding to infection and vaccination, informing better breeding practices to produce more disease-resistant animals. These efforts are helping to shape novel vaccine designs that could benefit both human and animal health.
Vaccine delivery
Understanding mucosal immunity is important for designing next-generation vaccines that can stop viruses at the site of entry. Researchers at Pirbright and the University of Oxford are exploring aerosol-based immunisation to deliver vaccines directly to the respiratory tract to stimulate a powerful local immune response. They have shown recently that aerosol-delivered viral vectored vaccines can induce protective T-cell responses in the pig lung, offering significant protection against influenza.3, 4
By focusing on T-cell responses, rather than just antibodies, this work paves the way for next-generation vaccines that could provide robust protection across multiple influenza strains and is a critical step towards a universal flu vaccine.
Beyond viruses – pigs as models for human diseases
While pigs play a crucial role in studying respiratory viruses, their value as a biomedical model extends far beyond infectious disease research. Over the last decade, the development of genetically modified pigs has revolutionised the study of human disorders, enabling breakthroughs in metabolic, genetic, cardiovascular and neurodegenerative diseases. With physiological and immunological similarities to humans, pigs provide a superior system for understanding disease mechanisms in ways that small animal models often cannot.
Pirbright’s expertise includes a recent multi-disciplinary study examining the effects of cystic fibrosis on the immune system.5 Using pig models, researchers are uncovering how the immune system responds to chronic lung infections, a key challenge for cystic fibrosis patients. “Cutting-edge research with swine as an animal model not only improves human health, but also benefits livestock health through the development of refined tools and a better understanding of the porcine immune system,” said Dr Wilhelm Gerner, T-Cell Biology Group Lead at The Pirbright Institute.
The way ahead
With climate change, biodiversity loss and increased human–animal interactions heightening the risk of zoonotic spillovers, the next pandemic is not a matter of if but when. One Health approaches that integrate human, animal and environmental health are more important than ever. Large animal models, including pigs, are helping to fill knowledge gaps in our understanding of immunity, and beyond, informing vaccine development and research into chronic inflammatory conditions.
Livestock immunology research also plays a vital role in global food security, helping to protect the health of animals that provide high-quality protein for billions of people. Advances in T-cell immunity research, mucosal and aerosol-based immunisation hold significant promise, not only for influenza and coronaviruses, but also for tackling other respiratory diseases.
By fostering collaboration between animal and human immunologists, geneticists, virologists and epidemiologists, institutes like Pirbright will be central to ensuring that future pandemics can be mitigated before they begin.
References
1 Muir et al. 2024 PLOS Pathogens 20 e1011910 https://doi.org/10.1371/journal.ppat.1011910
2 4 Schwartz et al. 2024 Immunogenetics 76 361–380 https://doi.org/10.1007/s00251-024-01355-7
3 Vatzia et al. 2023 npj Vaccines8 19 https://doi.org/10.1038/s41541-023-00620-2
4 Vatzia et al. 2024 npj Vaccines 9 188 https://doi.org/10.1038/s41541-024-00989-8
5 Jaudas et al. 2025 Sci. Trans. Med. 17 eadk9145 https://doi.org/10.1126/scitranslmed.adk9145