Pre-existing coronavirus antibodies could help protect children against new pandemic strain
9 November 2020
Researchers at the Francis Crick Institute and University College London have found that some antibodies, created by the immune system during infection with common cold coronaviruses, can also target SARS-CoV-2 and may confer a degree of protection against the new viral strain.
There are several coronavirus strains which are known to infect humans, some of which are common in the UK and cause mild illness like coughs and common colds. When we encounter viruses like coronaviruses, the immune system makes antibodies to help fight it. These antibodies can remain in the body for many years, and if re-infection happens, help to tackle the virus again.
In their paper, published in Science, the scientists found that some people, notably children, have antibodies reactive to SARS-CoV-2 in their blood, despite not ever having being infected with the virus. These antibodies are likely the result of exposure to other coronaviruses, which cause a common cold and which have structural similarities with SARS-CoV-2.
The researchers were working on the development of a highly sensitive antibody test when they decided to test samples collected before the pandemic between 2011 & 2018 to check that the test was working. To their surprise they found that some samples in people who had never been exposed to SARS-CoV-2 contained COVID-19 recognising antibodies which also recognise the new virus. Notably, such cross-reactive antibodies were found much more frequently in blood samples taken from children and young people aged 6 to 16.
Kevin Ng, lead author and post-graduate student in the Retroviral Immunology Laboratory at the Crick says:
“Our results show that children are much more likely to have these cross-reactive antibodies than adults. More research is needed to understand why this is, but it could be down to children being more regularly exposed to other coronaviruses. These higher levels we observed in children could also help explain why they are less likely to become severely ill with COVID-19. There is no evidence yet, however, that these antibodies prevent SARS-CoV-2 infection or spread.”
George Kassiotis, senior author and group leader of the Retroviral Immunology Laboratory at the Crick says:
“It is important to stress that there are still many unknowns which require further research. For example, exactly how is immunity to one coronavirus modified by exposure to another? Or why does this activity decline with age? It is not the case that people who have recently had a cold should think they are immune to COVID-19.”
Professor Lucy Wedderburn , Director of the Centre for Adolescent Rheumatology Versus Arthritis at UCL, UCLH and GOSH and lead of the MRC-funded CLUSTER Consortium for childhood arthritis says:
“We were delighted to collaborate with the researchers at the Crick in this important study, especially since we know that children seem to suffer far less from the SARS-CoV2 virus. Importantly the work with Prof Kassiotis and his team is ongoing, to find out whether our patients with arthritis and related rheumatic diseases also have these protective antibodies from previous coronavirus infection, that could help to protect them against COVID-19.”
istockphoto.com/ Credit: koto_feja
- Centre for Adolescent Rheumatology Versus Arthritis
- Infection, Immunity and Infllammation Research and Teaching Department, UCL Great Ormond Street Institute of Child Health
- Paper in Science
- The Francis Crick Institute