IL7 and COVID-19: Quantitative reverse-transcriptase PCR (qRT-PCR) analysis showed a time-dependent upregulation of inflammatory cytokines and chemokines including IL-7, IL-8, tumor necrosis factor-α (TNF-α), CXCL10, and CCL5 in the virus-infected cells (Fig. 1a), of which upregulation were also reported in the COVID-19 patients.13 Furthermore, SARS-CoV-2 infection of Calu-3 cells induced IL-1β processing and secretion in an multiplicity of infection (MOI)-dependent manner (Fig. 1b).