Groundbreaking research, published in Nature Immunology, has identified that killer T cells can fight all influenza viruses creating the potential for the development of a world-first universal, one-shot flu vaccine.
The collaborative international research team investigated the breadth of CD8+ T cell cross-recognition and provided evidence of CD8+ T cell cross-reactivity across A, B and C influenza virus (IAV, IBV, ICV) strains.
Using mass spectrometry they identified immunodominant CD8+ T cell epitopes from IBVs that were protective in mice and found memory CD8+ T cells directed against universal and influenza-virus-type-specific epitopes in the blood and lungs of healthy humans. Lung-derived CD8+ T cells displayed tissue-resident memory phenotypes. Notably, CD38+Ki67+CD8+ effector T cells directed against novel epitopes were readily detected in IAV- or IBV-infected pediatric and adult subjects.
The research team then attempted to find robust responses to those viral parts in healthy and influenza-infected subjects. “Our immunisation studies with the peptide responsible for activating the killer T cells revealed remarkably reduced levels of flu virus and inflammation in the airways,” study author Marios Koutsakos said.
The researchers are now examining immunity in high-risk ethnic groups, including indigenous Australians and Alaskans, who might not share the same immune response as those investigated by this study.