CXCL10 and COVID-19: In general, CXCL10 levels in the serum were higher than in the CSF for the entire COVID-19 cohort (serum = 405.2 pg/ml, 32.8–234.3 pg/ml versus CSF = 226.7 pg/ml, 49.1–622.1 pg/ml) resulting in CSF/serum ratios in between 0.53–0.59 pointing at a cytokine origin from outside of the CNS.