20 Dec 2024
Findings provide “critical insights” into how immune responses can be measured from blood samples, providing a foundation for future testing of mucosally administered vaccines.
Paul Imrie
Job Title
Image: The Pirbright Institute
A study of pigs that showed inhaled vaccines could potentially reduce viral transmission and boost vaccine efficacy could have big implications for human research.
Scientists have been interested in administering vaccines mucosally, rather than by IM injections, since the SARS-CoV-2 pandemic was declared in 2020.
Teams at The Pirbright Institute and the University of Oxford used pigs as a model to explore immune system responses to mucosally administered flu vaccines.
Because a comprehensive measurement of immune responses in human lungs is not possible, researchers used pigs as their respiratory tract is anatomically and functionally similar to humans.
Samples collected from both the lungs and blood of vaccinated pigs, aided by mathematical modelling, showed lung responses can be predicted from blood tests, making it easier to assess vaccine effectiveness in humans.
Simon Gubbins, head of transmission biology at The Pirbright Institute, said: “To bring future vaccines to market, it is critical to define the correlates of protection – markers that can reliably predict the effectiveness of the vaccine, in humans.
“Our study explored potential assays, sampling times and sample types (such as blood and lung samples), which could define correlates of protection in humans.”
Dame Sarah Gilbert, Saïd professor of vaccinology at the Pandemic Sciences Institute at the University of Oxford, said: “The research found that immune responses in the blood could reliably reflect those in the lungs, thus offering a practical way to assess the effectiveness of vaccines targeting the respiratory system.
“The findings provide critical insights into how immune responses can be measured from easily accessible blood samples and are a foundation for future testing of mucosally administered vaccines in clinical trials.”
The findings of the study, published in Frontiers in Immunology, lay foundations for development of human respiratory vaccines, the researchers said.
