THBS1 and COVID-19: Ontology terms underlying the connectivity of large-effect regulator genes revealed signaling associations including ECM deposition (collagen family members) and fibroblast activation (STAT3, THBS1) in fibroblasts (43, 44), further emphasizing that dysregulated fibroblast activity is a salient feature of COVID-19–associated cardiac microthrombi (Supplemental Figure 6).