Calming the Cytokine Storm

Evasins – proteins released by ticks to switch off inflammatory cytokines when they are sucking blood – are being investigated as a potential therapeutic avenue for COVID-19.

Biotech company ILC Therapeutics actually began collaborating with Shoumo Bhattacharya and his team at the University of Oxford, UK, in 2019, but the project took on a new direction – and increasing urgency – when the group realized how serious the COVID-19 pandemic was becoming. “My colleague, Alan Walker [CEO of ILC Therapeutics] likes to say that we didn’t come looking for COVID-19, it came looking for us,” says Bill Stimson, Chief Scientific Officer at ILC Therapeutics. 

“Cytokine storms, which are associated with many respiratory diseases, are triggered by viral infection and cause the release of many inflammation-driving chemokines in the lungs,” says Stimson. The overproduction of these pro-inflammatory cytokines results in lung damage and is associated with the onset of acute respiratory distress syndrome (ARDS) – a major cause of COVID-19-related death. 

“We have combined three types of Evasins, and our early studies show that they can bind to the chemokines released during the cytokine storm, preventing the inflammatory response of all these chemical messengers, and thus treating ARDS,” says Stimson. One potential advantage of the approach is that Evasins target the host’s backfiring immune response rather than the viral trigger; “If Evasins do prove to be suitable treatments for COVID-19, it is highly likely they will be beneficial in other viruses in the future that cause ARDS too.”