A review article by Ronco and Debiec gives a summary on current knowledge regardings membranous nephropathyv(MN). It takes 20 years since the identification of the protein megalin in Heymann nephritis, the prototype of human membranous nephropathy, in rats, until the first identification of such antigen in human. Although uncommon cause of human MN, autoantibody to neutral endopeptidase (NEP) was found to be the cause of neonatal MN in infants whose mothers genetically lacked this protein. The identification of phospholipase A2 receptor in 70% of idiopathic MN is a major breakthrough in the quest for pathogenic antigen of this common glomerular disease. But as the title of this article indicates, there are still challenges before effective treatment can be established. The way in which the antigen induces autoantibody is still unclear. Multiple antigens could be involved in immune complex formation and may be at different stages of disease. The treatment targeted B lymphocyte was variable in effectiveness.
