The coronavirus SARS-CoV-2 causes the COVID-19 pandemic, and effective treatment options for COVID-19 are urgently needed. SARS-CoV-2 viruses have glycoprotein “spikes” on their surface. These spikes help the virus to enter host cells by binding to a receptor on the surface of the host cells’ membrane—the angiotensin-converting enzyme 2 (ACE2). In severe cases of COVID-19, patients show elevated levels of inflammatory cytokines, signaling molecules important for the immune system. Such a “cytokine storm” can lead to life-threatening disease or even fatal outcomes.
Lu Lu, Youhua Xie, Shibo Jiang, Fudan University, Shanghai, China, Xiaoyuan Chen, National Institutes of Health (NIH), Bethesda, MD, USA, and colleagues have developed a nanodecoy made from engineered cell membranes that could neutralize both the virus and inflammatory cytokines. The team first genetically engineered human embryonic kidney 293T cells to express the ACE2 receptor. Then they collected cell-membrane nanovesicles from these engineered 293T/ACE2 cells and from THP-1 cells, a cell line that has abundant cytokine receptors. These two types of cell membrane were mixed to give fused nanovesicles via sonication and extrusion of the cell membranes through nanopores.
The resulting nanodecoys contain both abundant ACE2 receptors and cytokine receptors from the source cells. These nanodecoys can compete with healthy cells and bind both the SARS-CoV-2 virus and inflammatory cytokines, such as interleukin 6 (IL-6) and granulocyte-macrophage colony-stimulating factor (GM-CSF). The team used a mouse model for acute lung inflammation to show that the nanodecoys can prevent lung injury. However, the researchers point out that further studies and optimization will be necessary before such nanoparticles can be used to fight COVID-19.
- Decoy nanoparticles protect against COVID-19 by concurrently adsorbing viruses and inflammatory cytokines,
Lang Rao, Shuai Xia, Wei Xu, Rui Tian, Guocan Yu, Chenjian Gu, Pan Pan, Qian-Fang Meng, Xia Cai, Di Qu, Lu Lu, Youhua Xie, Shibo Jiang, Xiaoyuan Chen,
Proc. Natl. Acad. Sci. USA 2020.
https://doi.org/10.1073/pnas.2014352117
Also of Interest
- Collection: SARS-CoV-2 Virus
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