First Identification of an Antigen in Autoimmune Idiopathic Membranous Nephropathy: Toward Targeted Therapy?

Proposed scheme of in situ formation of immune deposits in membranous nephropathy (MN). The in situ formation of immune complexes involves circulating antibodies binding to a native podocyte protein. Two antigenic targets have been identified: neutral endopeptidase (in alloimmune MN) and phospholipase A₂ receptor (in idiopathic MN). In both cases, the pathogenic antigens are integral glycoproteins of podocytes. The formation of subepithelial immune deposits and complement activation are responsible for functional impairment of the podocytes and proteinuria.