Figure 1. Transcriptional changes in lung induced by COVID-19 infection did not alter F3, but decreased aPC anticoagulant capacity, suggesting decreased inhibition of the propagation phase of coagulation.

Figure shows differential gene expression (log₂ fold change) of coagulation pathway transcripts in BALF of COVID-19 patients; the image illustrates mechanistic relationships of the protein products of the identified transcripts during coagulation. Shading indicates relative expression in COVID-19 patients compared to controls: increased (red) or decreased (blue). There was minimal change in F3 (encoding tissue factor ) and increased TFPI (encoding the major inhibitor of tissue factor activity). There was decreased THBD, PROCR, and PROS1 (encoding proteins that enhance anticoagulant activity) and increased SERPINA5 (encoding protein C inhibitor). There was also decreased SERPING1 (encoding C1-Inhibitor). Other transcripts showing changes (e.g., F11, F10, F7, F2) encode proteins typically produced in the liver; local expression of these proteins is unclear.