Researchers are one step closer to understanding the mechanisms behind "cytokine storms," an immune system reaction that can cause severe COVID-19 symptoms in patients infected with the coronavirus. In a new paper published in the journal Cell, scientists from St. Jude Children's Research Hospital describe their identification of the specific cytokines, or small proteins, that are produced by the body in an effort to fight the virus but sometimes overreact and wind up causing damage, including inflammation, lung injury, and organ failure.
After examining the many different kinds of cytokines in the body, researchers determined that no single cytokine caused this inflammatory response. Instead, it appears to be a combination of two specific cytokines, dubbed tumor necrosis factor (TNF)-alpha and interferon (INF)-gamma, that work in collusion to cause inflammatory cell death.
By identifying these proteins as the culprit, researchers suggested that administering neutralizing antibodies and disrupting the protein pathways that promote cell death might present a new treatment method for COVID-19.
"Understanding the pathways and mechanism driving this inflammation is critical to develop effective treatment strategies," co-author Thirumala-Devi Kanneganti, vice chair of St. Jude's department of immunology, said in a press release. "This research provides that understanding. We also identified the specific cytokines that activate inflammatory cell death pathways and have considerable potential for treatment of COVID-19 and other highly fatal diseases, including sepsis."
Thus far, this theory has only been tested in mice, which received neutralizing antibodies and were protected from severe COVID-19 symptoms. But in isolating the exact cytokines involved, it will likely be easier to locate an effective treatment, either from an existing drug or one developed specifically for the task. In time, researchers hope clinical trials of select drugs can be another tool in the fight against the virus.