Broad T-cell response is currently protective but recognition of seven out of ten T-cell targets mutated in SARS-CoV-2 variants is impaired
As new variants of concern are discovered, scientists say they will need to check how immune systems are able to recognise and defend against SARS-CoV-2
Immune T cells are continuing to target the spike protein of SARS-CoV-2 variants of concern, although mutations are making some T cells less effective, according to new research.
Published in Nature Immunology, researchers from the University of Birmingham have shown that human T cell immunity is currently coping with mutations that have accumulated over time in COVID-19 variants.
In the study, funded by the National Institute for Health and Care Research, the research partner of the NHS, the researchers tested CD4+ T cells collected at the start of the pandemic from healthcare workers infected with COVID-19.
Some of the T-cells were still able to recognise parts of the spike protein, called epitopes, unaltered in later virus strains including the current Omicron variant. However, T cell recognition was worse against seven out of ten epitopes mutated in different variants of concern.
The researchers caution that as SARS-CoV-2 continues to mutate, T-cell recognition of additional epitopes could be lost decreasing overall protection by the immune system.
Dr Heather Long, Associate Professor in the Institute of Immunology and Immunotherapy at the University of Birmingham and lead author of the research said:
“Our paper shows that although most people have a diverse T cell response against the virus, some responses are less effective against Omicron. As further variants of concern are identified we will need to consider carefully how new viral mutations affect T-cell recognition.”
As further variants of concern are identified we will need to consider carefully how new viral mutations affect T-cell recognition.
Dr Graham Taylor, Associate Professor in the Institute of Immunology and Immunotherapy at the University of Birmingham said:
“The vaccines currently in use are still vital to protect us from COVID-19. Should SARS-CoV-2 continue to mutate to evade the immune system, our findings will help researchers to develop new vaccines better suited to those variants.”
NIHR is funded by the Department of Health and Social Care. Its work in low and middle income countries is principally funded through UK Aid from the UK government.
Associate Professor
Contact details and biography for Dr Heather Long, Researcher in the School of Cancer Sciences at the University of Birmingham.
Senior Lecturer in Tumour Immunology
Staff profile for Dr Graham Taylor, Senior Lecturer in Tumour Immunology, Institute of Immunology and Immunotherapy, College of Medical and Dental Sciences, the University of Birmingham
