Focusing on DCs (Fig 2C), we found a significant relative reduction of cDC1 (CD123– CD141+ CD1clo), cDC2 (CD123– CD141lo CD1c+ CD5+), DC3 (CD123– CD141lo CD1c+/int CD5–) and pDC (CD123+ Axl−Siglec1–) within the Lin−HLA-DR+ CD88/89– CD16– population in COVID-19 patients compared to controls. Here, MPPE1 is linked to COVID-19.