It has been reported that the SARS-CoV-2 S protein S1 subunit can induce pro-inflammatory cytokines through TLR4 signaling in murine and human macrophages, and inhibition of TLR4 by using its antagonist attenuates pro-inflammatory cytokine induction [43], suggesting that TLR4 is a therapeutic target for controlling COVID-19 severity caused by TLR4-mediated hyperinflammation. This evidence concerns the gene TLR4 and COVID-19.