Commonalities between COVID-19 and arthritis could lead to new treatments for long-COVID

30 July 2021

Research led by Dr. Mariola Kurowska-Stolarska of the Research into Inflammatory Arthritis Centre Versus Arthritis (RACE) in collaboration with Prof. Elisa Gremese at Fondazione A.Gemelli IRCCS, Italy has found similarities in immune cells knowns as macrophages within the lungs of patients with severe COVID-19 and in the joints of rheumatoid arthritis (RA) patients.

These findings could help develop new treatment strategies for severe COVID-19 and post-COVID-19 syndrome, or long COVID.

Read the findings published in the peer-reviewed Journal of Clinical Investigation (JCI) Insight.

What did researchers discover?

Macrophages are immune cells responsible for removing harmful pathogens, such as viruses from the body. However, when over-activated they can cause inflammation that causes tissue damage.

Researchers found that these cells express a gene called SPP1, and levels of this molecule are high in blood of people with COVID-19. This gene causes the macrophages to produce a protein known as osteopontin that may contribute to inflammation.

The science behind the research

The researchers also discovered:

  • Measuring SPP1 levels could help to predict if people would need treatment in intensive care.
  • People who recovered from severe COVID-19 and were virus negative, but with persistent symptoms, still had abnormally high blood levels of SPP1, despite normal levels of other pro-inflammatory molecules.

This all suggests the molecule could play a role in long-COVID-19.

Why is this research important?

Dr Caroline Aylott, Head of Research Delivery at Versus Arthritis, said: “In both rheumatoid arthritis and COVID-19, the immune system attacks the body's own tissues, causing inflammation and damage.

This research is a step forward in understanding why inflammation continues in both rheumatoid arthritis and COVID-19 and may provide a potential target for the future treatments for both conditions.

Understanding our immune system is key to helping the 18 million people who experience the pain and fatigue linked to arthritis. Versus Arthritis research funding may be unlocking the prospects of future treatment not only for arthritis but also for long COVID.”

How will this research benefit future treatments?

Lucy MacDonald, RACE Versus Arthritis, PhD student and one of the first lead authors of the study, said:

“By understanding this commonality, we have now identified SPP1 as a potential therapeutic target. Our goal is to improve the treatment for patients with COVID-19 and post-COVID-19 as well as for our rheumatoid arthritis patients.”

The study was funded by the Medical Research Council, Versus Arthritis and the Italian Ministry of Health. Find out more on our research.

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