Membranous glomerulopathy is an autoimmune disease caused by autoantibodies directed against kidney podocyte antigens. Determination of the target autoantigen has diagnostic significance, informs prognosis, and allows for non-invasive monitoring of disease activity in serum. Many cases of membranous glomerulopathy can be classified according to the target autoantigen as either phospholipase A2 receptor (PLA2R) or thrombospondin-type-1-domain containing 7A (THSD7A)-associated disease. The autoantigenic targets for the remaining cases of membranous glomerulopathy are yet to be determined, and the goal of this project is the identification of these unknown antigens. We have developed an interactive R-based omics data visualization tool to aid in this analysis. Here we demonstrate that mass spectrometry of laser capture microdissected glomeruli can identify the antigenic etiology of membranous glomerulopathy. We utilized mass spectrometry for antigen discovery of laser capture microdissected glomeruli from FFPE and tissue IgG immunoprecipitation studies from frozen tissue. Mass spectrometric analysis of laser capture microdissected glomeruli with 23 cases of membranous glomerulopathy (MG) including 3 PLA2R-positive MG, 2 THSD7A-positive MG, and 15 cases of membranous that were negative for PLA2R and THS7DA, and 3 lupus membranous. A total of 1695 proteins were identified in this analysis. For each known membranous type, protein differential abundance was compared against the remaining groups by normalized iBAQ values. Statistical analysis was performed within the interactive R-tool, which showed meaningful differences between different subtypes of membranous glomerulopathy. PLA2R was significantly more abundant in cases of PLA2R-associated MG and showed the strongest fold change. THSD7A displayed the strongest fold changes in THSD7A-associated MG. Several proteins were seen uniquely in the PLA2R/THS7DA negative membranous or lupus membranous cases. Immunohistochemistry analysis of kidney biopsy specimens to determine their specificity is being performed.