Posted: 9 November
New research from the Peter Doherty Institute of Infection and Immunity (Doherty Institute), The University of Melbourne and WEHI has unlocked key information in our understanding of molecular immune responses to COVID-19.
Following COVID-19 infection, virus-specific antibodies are generated, which can both neutralise the virus and clear the infection. While much has been said about the importance of Immunoglobulin G (IgG) antibodies for protection and control of SARS-CoV-2, the study of the role of Immunoglobulin A (IgA) antibodies against SARS-CoV-2 has been relatively neglected throughout the pandemic. Until now.
In a paper published in Clinical & Translational Immunology, the scientists conducted an experimental study to compare antibody responses to the virus in blood serum from people who had recovered from COVID-19.
University of Melbourne’s Samantha Davis, PhD Researcher at the Doherty Institute, is the lead author of the paper.
“In simple terms, we’ve deconstructed blood in our lab to measure its ability to smother the virus and to activate immune cells to kill SARS-CoV-2,” Ms Davis explained.
“While we knew that IgG is very important in the antibody response to clear the virus, we discovered that IgA also plays a key role in neutralising it in most people.”
As neutralising antibodies are an indicator of immune response and protection against viral infections, this discovery is critical in the context of vaccine development.
University of Melbourne’s Dr Amy Chung is a Laboratory Head the Doherty Institute and one of the senior authors of the paper.
“This research opens the door to new approaches for the development of future vaccines against SARS-CoV-2,” Dr Chung said.
“Our findings are particularly important as IgA is the most abundant antibody present in the mucosa of our respiratory tract, which is the main route of virus infection. This means if we’re able to specifically make these antibodies at these vulnerable sites, we now know that we can induce a robust immune response to protect against the virus.”
The research was funded by grants from the National Health and Medical Research Council (NHMRC), the Medical Research Future Fund (MRFF), Mercatus Center Emergent Ventures and the Paul Ramsay Foundation.