Walter and Eliza Hall Institute researchers have identified a molecular switch that impacts immune responses to viral infections, and whether or not protective antibodies are produced.
The team also made the discovery that the immune system protects against different viruses via distinct pathways. Their findings could lead to better strategies to develop vaccines for previously hard-to-prevent viruses. The research, led by Joanna Groom and PhD student Amania Sheikh, was published in the journal Cell Reports.
Researchers have identified that the protein T-bet determines how the immune system responds to viral infections. The research showed that T-bet enables immune T cells to distinguish between different viral infections, controlling whether or not protective antibodies are produced.
Antibodies are an essential component of long-lived immunity to viruses, and this discovery could underpin the development of better vaccines to prevent viral diseases, according to the researchers.
Our immune system comprises a complex network of cells and signaling molecules that can produce a range of responses to infections, Sheikh said. “Immune T cells are critical for coordinating specific immune responses, recruiting other cells and directing how we respond to different microbes such as bacteria, fungi or viruses,” she said.
“We knew that the protein T-bet was important for the function of many immune cells, and wanted to understand its role in a subset of immune T cells that help in the formation of protective antibodies.”
Antibodies are long-lived proteins that can be produced following an infection. They specifically bind to other proteins – such as those on a microbe’s surface – and are important for protecting us against repeat infections by the same microbe. Vaccines work by stimulating the production of antibodies that are specific to an infectious disease, preventing the infection from establishing.
Sheikh said the team discovered that T-bet was an essential switch that enabled T cells to stimulate antibody production in response to viral infections. “The level of T-bet in T cells is influenced by factors such as how a virus enters the body, and how much inflammation it triggers in its early stages. This in turn influences the immune response to the virus,” she said.