Notably, through single cell RNAseq analysis of T-cell dysregulation in severe COVID-19 it has been demonstrated that CD4+ T cells from severe COVID-19 patients expressed higher levels of a set of inflammatory genes that include FOS, FOSB, JUN and others, gene expression (40) not dissimilar to those found in our M-specific TCLs derived from SARS-CoV-2 unexposed individuals. Here, FOS is linked to COVID-19.