Cytokine storms play a limited role in moderate-to-severe #COVID-19 | EurekAlert! Science News
“The lack of hyperinflammation in most COVID-19 patients does not mean they had less disease,” said co-first author Jeremy Chase Crawford, Ph.D., of St. Jude Immunology. “We are saying that in most cases the disease was not caused by broad hyperinflammation from cytokine storm, which has important implications for developing generalizable COVID-19 therapeutics.”
The analysis revealed that the antiviral immune response was profoundly suppressed in COVID-19 patients compared to flu patients. Along with measuring cytokines, researchers analyzed cytokine transcription in individual blood cells in patients with flu, COVID-19 and healthy volunteers. COVID-19 was associated with significantly reduced production of and response to Type I and Type II interferons, cytokines that play a central role in the antiviral immune response.
Researchers also found evidence that SARS-CoV-2 alters pathways controlling the immune response to promote steroid production by patients. “Our results suggest that most COVID-19 patients are perhaps already producing high levels of glucocorticoids prior to treatment, possibly leading to the blunted immunity we see in most of them,” Thomas said. “These patients may need therapy to turn up their immune response to knock the virus down.”