The study is one of three new UK-wide studies receiving a share of £8.4 million from UK Research and Innovation (UKRI) and the National Institute for Health Research (NIHR).

The Humoral Immune Correlates of COVID-19 (HICC) consortium will study the humoral immune response - molecules produced by the immune system to fight infection, including antibodies – by focusing on two cohorts: NHS workers - in collaboration with SIREN - to track immunity over 12 months, and hospitalised patients.

It will look in detail at the role of antibodies in immunity to SARS-CoV-2 and characterize the antibody response in people who have mild or asymptomatic infection versus those who develop moderate or severe COVID-19 disease. The researchers want to better understand the differences between beneficial - or protective - antibody responses versus those that cause disease. This will help to determine why early indications suggest that people with stronger antibody responses may have had more life-threatening disease and what types of antibody responses are more effective in preventing severe infection.

The results from the study will help to develop better tests to diagnose protective immunity as well as determine how long protective antibodies persist after exposure to the virus. The researchers also hope the study will inform treatments for COVID-19 patients at different stages and with different severities of the disease, including whether targeting the overactivation of the innate humoral immune response – known as the ‘complement system’ – to SARS-CoV-2, could provide a unique approach to reducing severe COVID-19 related disease and death.

The consortium is a collaboration led by Professor Wilhelm Schwaeble and Professor Jonathan Heeney at the University of Cambridge, and Dr Helen Baxendale at the Royal Papworth Hospital NHS Trust.

“Understanding the role of antibody responses to SARS-CoV-2, and the role that the overactivation of the immediate innate immune response to the virus plays through complement activation in the initiation and maintenance of inflammatory disease, is critical to improve the clinical management of life-threatening cases of COVID-19,” said Dr Baxendale.

“In critical care, we know most patients have high levels of antibody to SARS-CoV-2 however what we don’t know is whether these antibodies are helpful. Pilot data has shown that many of our NHS staff have been exposed to SARS-CoV-2, but we need to find out whether this means they are protected from further infection either in the short or the long term, or may be at risk of disease in the future. Understanding the different types of antibody responses will allow us to determine beneficial antibodies from dangerous ones.

“Collaborating nationally with other UK COVID-19 projects and supported by clinical research networks and scientists across the country, we are delighted to receive this investment to answer these fundamentally important questions.”

HICC has been given urgent public health research status by the Department of Health and Social Care, to prioritise its delivery by the health and care system.

Chief Medical Officer for England and Head of the NIHR Professor Chris Whitty said: “Understanding how our immune systems respond to COVID-19 is key to solving some of the important questions about this new disease, including whether those who have had the disease develop immunity and how long this lasts, and why some are more severely affected.

“This investment by the NIHR and UKRI will help immunology experts to discover how our immune systems respond to SARS-CoV-2, including our T cell response. This is vital information to help prevent and treat the disease.”

Science Minister Amanda Solloway said: “Thanks to the brilliant work of our world-leading scientists and researchers, we continue to gain greater knowledge and understanding of coronavirus, enabling us to rapidly develop new treatments, as well as potential new vaccines.”