Notably, four MHC complex genes (HLA-DMA, HLA-DMB, HLA-DQA1 and HLA-DRB3), important for antigen-presenting function, as well as genes associated with monocyte adhesion and extravasation (SELL18), transendothelial migration (CD9919) and LPS signaling (MAP2K420) and MAP3K1421) were significantly downregulated in ARDS monocytes (Fig. 1l). Here, HLA-DMA is linked to acute respiratory distress syndrome.