The COVID-19 pandemic highlighted severe consequences of unchecked respiratory disease, including cytokine storms. This phenomenon affected many COVID-19 patients and is a potential side effect of many other diseases involving significant inflammation, but approaches to treating these symptoms remain unclear.
Researchers from the University of Osaka and other institutions report that a specially treated cell-derived product called a SPLEV strongly protects against the effects of cytokine storms. The findings have been published in Science Advances.
A cytokine storm is a runaway immune response that can be induced by infection, triggering severe systemic inflammation and causing respiratory failure, liver damage, abnormal blood clotting and, in some cases, death. There has been increasing interest in the role of extracellular vesicles—which are small membrane-wrapped packages of RNAs, proteins and fats—in treating this potentially life-threatening response. This interest stems from their known ability to fight excessive inflammation.
"Mesenchymal stem cell–derived extracellular vesicles are currently attracting attention as a potential treatment for cytokine storm," says lead author Shunya Nakayama. "However, we recently discovered that extracellular vesicles derived from liver cells are even more potent, and that their activity can be further enhanced by treatment with the secreted phospholipase A2 enzyme (sPLA2)."
The researchers treated liver cell extracellular vesicles with sPLA2 to generate sPLA2-reacted EVs, or SPLEVs. They then injected the SPLEVs into mice with acute respiratory distress syndrome and assessed the effects.
"The results were very clear," explains senior author Ai Kotani. "We found that the SPLEVs strongly suppressed lung inflammation, as evidenced by fewer immune cells in the lungs and considerably lower levels of cytokine production."
Intriguingly, the SPLEVs appeared to preferentially interact with the lung lining, unlike untreated extracellular vesicles, which targeted macrophages. Further analysis showed that they acted directly on lung epithelial cells to trigger massive production of tissue-protective lipids.
"We coined the term 'lipid counterstorm' to describe this effect, as it successfully counters the effects of a cytokine storm induced by lung disease," says Nakayama.
The SPLEVs also exhibited significant beneficial effects in mouse models of other inflammatory diseases, suggesting that they could be useful for treating sepsis, coagulopathy, liver injury, colitis and pneumonia. As lysophosphatidylglycerols increased following SPLEV treatment, the potential to develop inexpensive, cell-free artificial SPLEVs may be a valuable future therapeutic tool.
Publication details
Shunya Nakayama et al, sPLA2-reacted extracellular vesicles (SPLEVs) as a therapeutic modality for cytokine storm syndromes, Science Advances (2026). DOI: 10.1126/sciadv.adr9135. www.science.org/doi/10.1126/sciadv.adr9135
Who's behind this story?
MA in English, copy editor since 2021 with experience in higher education and health content. Dedicated to trustworthy science news. Full profile →
Bachelor's in mathematical biology, Master's in creative writing. Well-traveled with unique perspectives on science and language. Full profile →
Citation: Modified cell vesicles trigger 'lipid counterstorm' against lung inflammation in mice (2026, July 31) retrieved 31 July 2026 from https://phys.org/news/2026-07-cell-vesicles-trigger-lipid-counterstorm.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.