We are interested in defining diagnostic makers and molecular mechanisms for immune-mediated kidney diseases. For the diagnostics, we are identifying specific auto-antibodies that target the kidney. In 2009 we reported the identification of PLA2R as a target antigen for a condition call membranous nephropathy. Measurement of blood levels of anti-PLA2R is now a FDA approved test for this condition. We are now using a similar approach for lupus nephritis. We are also interested in using mass spectrometry techniques to identify the epitopes on PLA2R, with the goal of developing a blocking peptide therapeutic. For the mechanism studies, we have identified polymorphisms in an ABIN1 gene in association with lupus nephritis and show that mice with disrupted ABIN1 function develop this disease. We are now using proteomics to define protein-protein interaction and secretion of inflammatory mediators that are regulated by ABIN1 activity in kidney cells. We are also performing structural studies on mutant forms of ABIN1 that would result from different polymorphisms.