Marasmius oreades lectin induces renal thrombotic microangiopathic lesions

The present studies demonstrate that infusion of a type B specific lectin derived from the mushroom Marasmius oreades (MOA) into mice binds selectively to the glomerular endothelial cells via surface carbohydrate moieties resulting in cell injury and death associated with platelet-fibrin thrombi. This selective MOA binding to the endothelial cells can be abrogated by a sugar specific for the carbohydrate sequence. Hemolytic-Uremic Syndrome (HUS) and the closely associated Thrombotic Thrombocytopenic Purpura (TTP) are diseases associated with widespread microvascular injury in various organs. Clinically, these diseases are associated with microangiopathic hemolytic anemia and thrombocytopenia. The kidney glomerulus is a primary target of this microvascular injury. There are many underlying etiologies including bacterial toxins. Experimentally, such toxins injure endothelial cells in vitro but in vivo studies have failed to reproduce the characteristic renal pathology. We suggest that MOA-induced glomerular microangiopathic injury could be used to study the pathophysiology of endothelial cell injury as related to glomerular microangiopathic injury.