The sudden increase in rare autoimmune disease cases during the COVID-19 outbreak in the UK has led to the discovery of a new syndrome. This is the new autoimmune syndrome related to COVID-19 that can cause life-threatening lung disease.
The syndrome—referred to by scientists as “MDA5-associated interstitial lung disease concurrent with the COVID-19 pandemic,” or simply MIP-C—is a serious, rare condition in which the immune system mistakenly attacks the body. In the worst cases, the lungs can become so scarred and stiff that the only way to save the patient is through a full lung transplant.
Scientists have discovered an autoimmune syndrome that may be related to COVID-19. (Photo: Christoph Burgstedt/ Science Photo Library)
However, only a small fraction of cases are related to lung disease. Dr. Dennis McGonagle, a rheumatologist at the University of Leeds in the UK, who was the first to investigate the patterns of this new illness, stated: “Two-thirds of the studied cases do not have lung disease. But we found that 8 cases progressed rapidly and resulted in death despite all the high-tech therapies we could apply to them.”
In total, McGonagle and his colleagues have identified 60 cases of this syndrome so far. They published their findings in the May issue of the journal eBioMedicine.
McGonagle noted that this disease resembles the known condition MDA5 dermatomyositis, which primarily occurs in women of Asian descent. Patients experience joint pain, muscle inflammation, and skin rashes, and in two-thirds of cases, they suffer from life-threatening lung scarring. MDA5 dermatomyositis occurs when the immune system attacks one of its own proteins: a protein called MDA5 that typically helps detect RNA viruses. These viruses include those causing influenza, Ebola, and COVID-19.
McGonagle explained that the new research indicates that exposure to the RNA of the Coronavirus, a COVID-19 vaccine, or both can sometimes trigger the production of anti-MDA5 antibodies.
Typically, MDA5 activates when it senses viral RNA in cells and prompts the body to produce antibodies against the virus. However, in individuals with MIP-C, this immune response malfunctions. McGonagle suggested that either the body mistakes the MDA5 protein for a foreign protein and attacks it, or the RNA triggers such a strong immune response that the body’s own proteins, including MDA5, become targets of the immune attack.
Researchers found that the activation of IFIH1 was accompanied by a significant amount of an inflammatory protein called interleukin-15 (IL-15). IL-15 activates a layer of immune cells that typically destroy infected cells but can sometimes attack the body’s own cells.