Similarly, MCEMP1 and HLA-DRA, but not ETS1 expression, was significantly correlated with the type I IFN score, which captures the expression of 28 type I IFN-stimulated genes in myeloid and lymphoid cells21 and was previously demonstrated to be induced during severe COVID-19 and in children with multisystem inflammatory syndrome33 (Fig. 2d–f). Here, MCEMP1 is linked to COVID-19.