ISG15 and COVID-19: First, in myeloid cells from the lungs of COVID-19 patients (19), whose contact with infected epithelia would most closely mimic our experimental configuration, gene expression signatures of alveolar macrophages from severe patients proved up-regulated in our CoV2-cocultured monocytes (Fig. 5B, Left; chisq P < 10−4); some aligned with the swath equally affected in IAV- and CoV2-infected cocultures (including ISGs like IFI27 and ISG15), but the largest group belonged to the CoV2-specific quadrant (e.g., IL1B, TNF, CCL3, CD163, TIMP1, and PLAC8).