CXCL10 and COVID-19: Supporting this hypothesis, critical COVID-19 has been associated with high levels of interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), numerous interleukins (ILs), macrophage inflammatory proteins (MIPs), and IFN γ-induced protein 10 (IP-10) (1, 7, 8).