GFAP and Multiple Organ Failure: However, following SARS-CoV-2 infection, the expression levels of glial fibrillary acidic protein (GFAP), as an astrogliosis marker, are highly induced in patients with moderate to severe COVID-19 (127, 128), suggesting the possible role of reactive astrocytes along with aberrant microglial functions in shaping COVID-19-induced cytokine storm, leading ultimately to multiple-organ failure.