NIHR and UK Research and Innovation (UKRI) are streaming ￡8.4 million into three new UK-wide research studies aiming to understand immune responses to the novel coronavirus.

The researchers hope to develop better tests to define immunity, study the body’s immune response to SARS-CoV-2, and shed light on why some people suffer from severe life-threatening COVID-19 while others have mild or asymptomatic infections but can still transmit the virus.

Crucially, these studies are designed to determine when and how immunity persists or whether people can become re-infected.

The UK Coronavirus Immunology Consortium will receive ￡6.5 million to bring together leading immunologists from 17 UK universities that will investigate a series of questions, including: how long does immunity from COVID-19 last?; why are some people’s immune systems better able to fight off the virus; and how does the virus ‘hide’ from the immune system and how can this be addressed?

A better understanding of immune responses could provide targets for new therapies to treat COVID-19 and inform the efforts to develop a vaccine, the organisations noted.

“Understanding the complexities of the immune response to SARS-CoV-2 is key to successfully developing new diagnostics, treatments and vaccines against COVID-1,” said Professor Paul Moss, University of Birmingham, who leads the consortium.

“The UK Coronavirus Immunology Consortium will see the UK immunology community come together in an unprecedented way to answer questions that are crucial in helping us control this pandemic, such as how effective immunity is developed and why individuals respond differently to the disease.”

The Humoral Immune Correlates of COVID-19 (HICC) consortium is being given ￡1.5 million to explore the humoral immune response, focusing on NHS workers and hospitalised patients.

This study will look at the role of antibodies in immunity to SARS-CoV-2 and characterise the antibody response in people who have mild or asymptomatic infection versus those who develop moderate or severe COVID-19 disease.

The researchers are striving to increase understanding on the differences between protective antibody responses versus harmful ones, which will help determine why people with stronger responses may have had more life-threatening disease, and develop better tests to diagnose protective immunity.

“Understanding the role of antibody responses to SARS-CoV-2 and the critical role that overshooting immune system activation plays in driving the disease processes associated with COVID-19 is critical to optimising management of severe acute COVID-19 disease and developing the most effective vaccination strategies,” said Dr Helen Baxendale, Royal Papworth Hospital NHS Trust, one of the consortium's leaders.

“In critical care, we know most patients have high levels of antibodies to SARS-CoV-2; however, we don’t know whether these antibodies are helpful. Pilot data has shown that many of our NHS staff have been exposed to SARS-CoV-2, but we don’t know 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 types of antibody responses will allow us to determine beneficial antibodies from bad ones.”

The third study – Inflammation in COVID-19: Exploration of Critical Aspects of Pathogenesis, or ICECAP – will receive funding of ￡394,000 to focus on the key features of fatal COVID-19 and the impact the virus has upon the lungs and other vital organs.

Using hospital post-mortem examinations of patients who have died from COVID-19, the study will assess the effect of the disease on the whole body, analysing tissue samples collected during these examinations to collect crucial information on the presence of COVID-19 in multiple organs across the body.

The study is led by Dr Christopher Lucas at the University of Edinburgh, who said: “We have learned so much from COVID-19 patients during the past six months. However, there is only so much that we can learn from clinical examinations and blood tests.

“By having a deeper look at those who have died from COVID-19 through post-mortem examination, we will increase our understanding of what is happening to the body in the most severe cases of this disease. Critically, this will allow us to rapidly answer key clinical questions and help inform the care of patients and the development of new treatments.”