ATF4 and COVID-19: In severe relative to mild COVID-19 patient BALF, we observed downregulation of all eIF2B isoforms (eIF2B1-5; Figure 3A) and an upregulation of GADD34, ATF4, and CHOP, all indicative of increases in p-eIF2⍺, suggesting that severe COVID-19 patient BALF cells are likely in a translationally repressed state, driven by eIF2⍺ phosphorylation.