CCL3 and COVID-19: Systemic inflammation in patients with COVID-19 has been associated with elevated serum levels of pro-inflammatory cytokines and chemokines such as IL-2, IL-7, IL-8, IL-10, IP-10 (interferon-γ-inducible protein), MCP-1 (monocyte chemoattractant protein), MIP-1α (macrophage inflammatory protein 1 alpha), and TNFα.