Healthcare worker giving a COVID-19 vaccine to an adult man at the hospital

Research identifies immunosuppressed people are least likely to have COVID-19 antibodies

Wednesday, 23 August 2023

New research has identified which people with compromised immune systems are less likely to have COVID-19 antibodies - making them more vulnerable to a severe infection.

Around one in five people with solid organ transplant, rare autoimmune disease or blood cancer affecting lymphocytes had no COVID-19 antibodies after three or more vaccinations.

The MELODY study was carried out by a team of doctors and researchers from several institutions including Imperial College London, The Universities of Southampton, Nottingham, and Cambridge, Nottingham University Hospitals NHS Trust, NHS Blood and Transplant, the National Disease Registration Service at NHS England, and IPSOS MORI.

People were more likely to have antibodies if they were younger, had more vaccine doses (e.g. five vs three) or had previously had COVID-19. Some medications that weaken the immune system reduced the likelihood of having antibodies.

The findings published in The Lancet Rheumatology will help to better plan care and treatment for people living with these conditions. People who are less likely to have COVID-19 antibodies could be offered antibody testing and targeted interventions, such as further vaccine doses or preventative medicine. The absence of antibodies could also influence which immunotherapy medications are given to those with different underlying conditions.

Clinically vulnerable patients who are at increased risk are encouraged to attend if they are invited for a booster vaccine, to get the best protection against COVID-19.
Dr Michelle Willicombe, from the Department of Immunology & Inflammation at Imperial College London

Dr Michelle Willicombe, from the Department of Immunology & Inflammation at Imperial College London, who led the research, said: “We know from previous research that people who have a weakened immune system were more likely to catch COVID-19. They were also more likely to need to go into hospital for treatment or die from COVID-19.

“Vaccines trigger the immune system to make antibodies. But if your immune system is weak, you may not produce enough antibodies needed to fight infection and prevent serious illness. Clinically vulnerable patients who are at increased risk are encouraged to attend if they are invited for a booster vaccine, to get the best protection against COVID-19.”

People with suppressed immune systems could choose to enrol in the study if they had received at least three COVID-19 vaccine doses. More than 23,000 people took part by doing a home finger-prick antibody test and reporting the results using an online portal.

Participants also provided personal details (such as their age, gender and ethnicity), information about their condition, and their COVID-19 history, including number of vaccinations.

Antibodies were found in 77 per cent of people who had a solid organ transplant, 79 per cent of those with a blood cancer, and 86 per cent with rare autoimmune disease.

“This research shows that the majority of immunosuppressed people produce antibodies after having COVID-19 vaccines,” says Dr Fiona Pearce from the University of Nottingham. “Across all groups, we found that people who had had more doses of vaccine were more likely to have antibodies. In the future, this could help to develop bespoke booster vaccination schedules for more vulnerable groups.”

Dr Peter Lanyon, Consultant Rheumatologist, Nottingham University Hospitals NHS Trust and Rare Diseases Clinical Lead, National Disease Registration Service, NHS England said: “This study demonstrates the utility of national rare disease registration to identify and invite whole population-based cohorts of people to participate in research that answers important clinical questions and can inform clinical practice and health policy.”

Antibody prevalence after three or more COVID-19 vaccine doses in 23,000 immunosuppressed individuals: a cross-sectional study from MELODY is available online.

The research was funded by Funding for the Medical Research Council and health charities including Kidney Research UK, Vasculitis UK, Blood Cancer UK, and Cystic Fibrosis Trust.

Story credits

For further information, please email Dr Fiona Pearce, NIHR Advanced Fellow & Clinical Associate Professor, University of Nottingham at

Adam Mallaby - Media Relations Manager for the Faculty of Medicine and Health Sciences (Maternity Cover)
Phone: 0115 748 5719

Notes to editors:

About the University of Nottingham

Ranked 32 in Europe and 16th in the UK by the QS World University Rankings: Europe 2024, the University of Nottingham is a founding member of the Russell Group of research-intensive universities. Studying at the University of Nottingham is a life-changing experience, and we pride ourselves on unlocking the potential of our students. We have a pioneering spirit, expressed in the vision of our founder Sir Jesse Boot, which has seen us lead the way in establishing campuses in China and Malaysia - part of a globally connected network of education, research and industrial engagement.

Nottingham was crowned Sports University of the Year by The Times and Sunday Times Good University Guide 2024 – the third time it has been given the honour since 2018 – and by the Daily Mail University Guide 2024.

The university is among the best universities in the UK for the strength of our research, positioned seventh for research power in the UK according to REF 2021. The birthplace of discoveries such as MRI and ibuprofen, our innovations transform lives and tackle global problems such as sustainable food supplies, ending modern slavery, developing greener transport, and reducing reliance on fossil fuels.

The university is a major employer and industry partner - locally and globally - and our graduates are the second most targeted by the UK's top employers, according to The Graduate Market in 2022 report by High Fliers Research.

We lead the Universities for Nottingham initiative, in partnership with Nottingham Trent University, a pioneering collaboration between the city’s two world-class institutions to improve levels of prosperity, opportunity, sustainability, health and wellbeing for residents in the city and region we are proud to call home.

More news…

Media Relations - External Relations

The University of Nottingham
YANG Fujia Building
Jubilee Campus
Wollaton Road
Nottingham, NG8 1BB

telephone: +44 (0) 115 951 5798