Researchers have uncovered a promising approach to treat the respiratory issues associated with long COVID by pinpointing an unknown trigger for the condition within the lungs.
Researchers at the University of Virginia School of Medicine have discovered a potential therapy for the respiratory symptoms of long COVID, revealing an unidentified cause within the lungs.
Under the guidance of Jie Sun, PhD, the UVA research team found that COVID-19 infection induces substantial alterations in the immune cells located in lung tissues. This leads to scarring and persistent inflammation, even after the initial COVID infection has resolved. The researchers suggest that this prolonged inflammation contributes to the enduring respiratory symptoms, such as coughing and breathing difficulties, commonly associated with long COVID.
According to their recent findings, Sun and his colleagues propose that physicians might manage this chronic inflammation using certain classes of medications, like baricitinib, which are already utilized to treat rheumatoid arthritis. These anti-inflammatory drugs were previously granted emergency use authorization by the federal Food and Drug Administration (FDA) for severe COVID-19 cases displaying uncontrolled inflammation.
“Our study pinpointed a fundamental cause of the respiratory issues related to long COVID by conducting a comparative analysis of clinical samples alongside a suitable animal model,” stated Sun from UVA’s Carter Center for Immunology Research and UVA’s Division of Infectious Diseases and International Health. “We are optimistic that understanding these underlying mechanisms will enable us to carefully devise clinical studies that repurpose these FDA-approved drugs for long COVID soon.”
Millions Affected by Long COVID
It is estimated that over 60 million people worldwide suffer from long COVID. For these individuals, a COVID-19 infection can turn into an unending struggle, with symptoms that can linger for weeks, months, or even years. Long COVID symptoms can vary from uncomfortable to severely debilitating; respiratory issues may include shortness of breath, chest pain, and even chronic lung damage known as interstitial lung disease.
Previous investigations into long COVID have primarily focused on blood samples, but Sun and his team aimed to observe the changes occurring directly in the lung tissues. They analyzed cell samples collected from the lower airways of both lab mice and human subjects. Their findings showed that immune cells, specifically macrophages and T cells, had become dysfunctional and were engaging in damaging interactions. While these immune cells typically support the body in fighting infections, in this scenario, they continued their aggressive responses even after the initial COVID infection had cleared.
The researchers discovered a concerning influx of macrophages in abnormal quantities within the lungs, which contributed to tissue scarring. In parallel, T cells were producing interferon, a substance that perpetuates inflammation.
Sun and his team believe that physicians may be able to disrupt this inflammatory cycle using drugs already approved for treating harmful inflammation in rheumatoid arthritis, an autoimmune disease affecting joints. Although further research is essential, Sun expresses hope that their new findings will pave the way for innovative treatments for patients experiencing respiratory issues stemming from long COVID.
“We aspire for our clinical partners worldwide to initiate trials soon to evaluate the effectiveness of baricitinib or similar drugs that target the identical inflammatory pathways in long COVID,” Sun expressed. “Our research has laid a groundwork for discovering new therapeutic strategies for long COVID through a combination of comprehensive clinical testing and fundamental scientific exploration.”
Research Findings Released
The researchers have shared their results in the journal Science Translational Medicine. The research team included Chaofan Li, Wei Qian, Xiaoqin Wei, Harish Narasimhan, Yue Wu, Mohd Arish, In Su Cheon, Jinyi Tang, Gislane de Almeida Santos, Ying Li, Kamyar Sharifi, Ryan Kern, Robert Vassallo, and Sun. It’s worth noting that Sun received funding from Icosavax unrelated to this project; a detailed disclosure of the authors’ funding is available in the publication.
The National Institutes of Health supported this research with grants AI147394, AG069264, AI112844, AI176171, AI154598, and HL170961.
