Biochemical and biological properties of Lonomia obliqua bristle extract

Abstract

Lonomia obliqua caterpillar is frequently seen in accidents with humans especially in the south of Brazil. Patients develop a hemorrhagic syndrome that can be treated with specific antilonomic serum. A consumptive coagulopathy was found to be the main cause of bleeding complications observed in patients after contact with L. obliqua. Studies revealed that L. obliqua caterpillar bristle extract (LOCBE) displays a procoagulant activity that leads to intravascular thrombin formation, resulting in a special form of disseminated intravascular coagulation (DIC). Fibrinolysis seems to be secondary to the fibrin production, since no direct fibrinolytic activity was found in LOCBE. Two procoagulant toxins, a factor X activator (Losac) and a prothrombin activator (Lopap), were isolated from LOCBE and characterized. Infusion of Lopap into experimental animals triggered a condition similar to that observed in human envenomation.