A Non-Invasive Window into the Lungs
Researchers from Karolinska Institutet, Danderyd Hospital, and Uppsala University have successfully demonstrated that virus-specific antibodies can be measured in the small airways of the lungs using non-invasive sampling. Published in the journal eBioMedicine, the study utilized technology from the company PExA to collect samples from deep lung tissue, bypassing the need for invasive procedures such as bronchoscopy.
Mapping Localized Immune Responses
Led by Professor Charlotte Thålin of Karolinska Institutet, the research team analyzed samples from 28 individuals to identify IgA and IgG antibodies. The investigation focused on three primary respiratory viruses: influenza, SARS-CoV-2, and respiratory syncytial virus (RSV). The PExA instrument works by collecting exhaled breath particles, which are then processed via sensitive immunological methods to measure antibody levels with high precision.
The resulting data reveals distinct differences in antibody profiles across the blood, the nose, and the lower airways. This indicates that local immune responses within the lungs may diverge significantly from the systemic responses typically measured in the bloodstream.
Advancing Mucosal Vaccine Research
The capacity to monitor local immunity directly at the site of infection offers a new trajectory for pharmaceutical research. While current vaccine development often prioritizes systemic immune responses, researchers are increasingly focused on strengthening mucosal immunity within the respiratory tract.
“Being able to analyze antigen-specific antibodies in samples from the lower airways without invasive sampling gives us new opportunities to study the immune system in the lungs,” said Charlotte Thålin. She noted that this capability is particularly relevant for the development of future mucosal vaccines, which aim to provide protection exactly where pathogens typically enter the body.
Overcoming Analytical Barriers
A primary challenge in this field has historically been the minute volume of fluid collected during non-invasive breath sampling. The research team overcame this hurdle by employing advanced analytical methods capable of detecting specific antibodies in these tiny samples. Mikael Åberg, Associate Professor at Uppsala University and SciLifeLab, noted that this combination of non-invasive collection and sensitive analysis allows for the investigation of local immune responses that were previously difficult to study.
Drug Developers Monitor Treatment Effects with New Lung Disease Technology
For firms engaged in drug and vaccine development, the technology provides a method to monitor pharmacodynamics—how a treatment affects the body directly at the site of action. Tomas Gustafsson, CEO of PExA, stated that the company is already collaborating with pharmaceutical firms on various lung diseases and that these new findings could open an entirely new application area for their instruments.
While the study serves as a proof-of-concept for measuring virus-specific antibodies, the researchers intend for these methods to eventually support the comparison of vaccine candidates and the monitoring of immune responses over time.