APP and deep vein thrombosis: Furthermore, there were also some reported cases of LND/LNVs developing thrombosis [11]–[13] while APP is an important regulator of vein thrombosis and controls coagulation and neutrophil extracellular traps (NETs) formation via the Kunitz-type serine protease inhibitor (KPI)-containing the α soluble fragment of APP (APPsα fragment) that were demonstrated in vitro to be effective inhibitors of the coagulation FXa, FIXa, FXIa, and FVIIa:tissue factor complex [14].