Furthermore, the gene for the adapter protein SCIMP, a transmembrane scaffold for TLR4 that drives IL-6 production in macrophages and is expressed in B cells and other professional antigen-presenting cells at the immunological synapse via tetraspanin-enriched microdomains, has been implicated in COVID-19 lung hyper-inflammation and host-defense programs [38]. This evidence concerns the gene TLR4 and COVID-19.