New Study Links Lung Inflammation and Immune Cell Damage to Long Covid

A groundbreaking new study published in Science¹ has uncovered a critical mechanism behind the lingering lung damage seen in many patients with Long Covid, offering a potential path toward new therapies for the condition that continues to afflict millions worldwide.

The research, highlighted in a commentary by Alan Sariol and renowned virologist Stanley Perlman, explains how immune cell dysfunction in the lungs may be a key driver of post-acute sequelae of SARS-CoV-2 infection—commonly known as Long Covid.

According to the study by Wei et al., featured in the same issue (Vol. 387, Issue 6738), alveolar macrophages—the immune cells responsible for tissue repair in the lungs—lose vital organelles called peroxisomes after COVID-19 infection. Peroxisomes help regulate inflammation and process fatty acids. Their absence, the researchers found, prevents normal healing of lung tissue and leads to persistent scarring known as fibrosis.

The work was conducted in mice, which, despite species differences, have long been used as a model for studying respiratory diseases. In the experiments, animals infected with SARS-CoV-2 showed clear evidence of ongoing inflammation, defective repair, and tissue damage—a mirror of the symptoms seen in many human Long Covid patients, including difficulty breathing and reduced lung function.

“This study provides some of the clearest evidence yet that Long Covid is not just a lingering infection, but rather a consequence of immune system derailment,” said Dr. Perlman, a leading authority on coronaviruses. “If we can find ways to preserve or restore peroxisome function in these macrophages, we may be able to help patients recover more fully.”

The findings could mark a shift in how Long Covid is approached, moving the focus away from virus persistence toward repairing immune and cellular function.

With nearly 3,000 downloads since its release, the article is already drawing strong attention from the scientific community. Experts hope that this research will not only inform treatment strategies for Long Covid but may also provide insights into post-viral syndromes more broadly.

As millions continue to grapple with Long Covid, which includes not just respiratory issues but also neurological and cardiovascular symptoms, understanding the cellular damage behind these symptoms is more urgent than ever.

Further Reading:

Sariol, A., & Perlman, S. (2025). Lung inflammation drives Long Covid. Science, 387(6738), 1039–1040. https://doi.org/10.1126/science.adw0091

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