IL-13 Protects against SARS-CoV-2?

Peebles Jr discusses the paper by Bonser et al which examines the effects of IL-13 on SARS-CoV-2 infection of differentiated human bronchial epithelial cells (HBECs) cultured at an air-liquid interface. The authors report that IL-13 decreased viral RNA recovered from SARS-CoV-2-infected HBECs and reduced double-stranded RNA, a marker of viral replication. This IL-13-mediated inhibition of SARS-CoV-2 infection of HBECs was independent of either IL-13-induced mucus gel or SAM pointed domain-containing Ets transcription factor expression (SPDEF) , suggesting that IL-13 had antiviral effects unrelated to its ability to induce a mucus barrier. They also found that mucus inhibited SARS-CoV-2 infection of HBECs in cells not cultured with IL-13 compared with HBECs in which mucus had been removed by washing. The authors further performed bulk RNA sequencing from HBECs from six subjects who were cultured with IL-13 or IFN-α and were subsequently infected with SARS-CoV-2 and, not surprisingly, found that there were nonredundant differential effects of these cytokines on viral-induced gene expression.