“This is an important step toward human research,” Pirbright Institute at the University of Oxford said in a release. “Interest in administering vaccines mucosally, rather than by intramuscular injections, has been growing since the SARS-CoV-2 pandemic was declared in 2020.”
“Comprehensive measurement of immune responses in human lungs is not possible,” the researchers said, so they used pigs whose respiratory tract is similar to humans.
Samples collected from both the lungs and blood of vaccinated pigs, aided by mathematical modelling, showed that lung responses can be predicted from blood tests, making it easier to assess vaccine effectiveness in humans, the release 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,” said Dr. Simon Gubbins, head of transmission biology at The Pirbright Institute.
The findings of this study, published in Frontiers in Immunology have far-reaching implications for the future development of mucosally-administered vaccines in clinical trials, Pirbright said. The pig model’s ability to closely mimic human immune responses to respiratory infections make it an ideal platform for testing vaccine efficacy.
“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,” said Dame Sarah Gilbert, professor of vaccinology at the Pandemic Sciences Institute at the University of Oxford.
“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,” she said.
