PD21-02 NOVEL MECHANISMS OF INJURY IN MEMBRANOUS NEPHROPATHY

Abstract

You have accessJournal of UrologyCME1 May 2022PD21-02 NOVEL MECHANISMS OF INJURY IN MEMBRANOUS NEPHROPATHY Qi Zhang, Paolo Cravedi, Astgik Petrosyan, Valentina Villani, Roger De Filippo, Laura Perin, and Stefano Da Sacco Qi ZhangQi Zhang More articles by this author , Paolo CravediPaolo Cravedi More articles by this author , Astgik PetrosyanAstgik Petrosyan More articles by this author , Valentina VillaniValentina Villani More articles by this author , Roger De FilippoRoger De Filippo More articles by this author , Laura PerinLaura Perin More articles by this author , and Stefano Da SaccoStefano Da Sacco More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002559.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Primary membranous nephropathy (MN) is a leading cause of nephrotic syndrome in adults worldwide due to the deposition of anti-podocyte-anlibodies against in the glomerular subepithelial space. While complement deposition is thought to play a crucial pathogenic role, the exact effector mechanism of complement in MN is unclear due to the lack of in vitro and in vivo systems that recapitulate human disease. We have developed a novel glomerulus-on-a-chip system (GOAC) using human primary podocytes and glomerular endothelial cells (GEC) and assessed functional response to human MN serum, role of Membrane-attack-complex (MAC) formation and C3a/C3aR1 signaling in MN pathogenesis. METHODS: GOACs were cultured with serum containing either anti-PLA2R+ or THSD7A+ MN patients; sera from healthy individuals were used as control. Functional response was assessed by albumin permeability assay to evaluate permselectivity. Role of MAC and C3a/C3aR1 signaling pathway was assessed by immunofluorescence and functional analysis while mechanisms of action were explored by PCR arrays, Western Blotting and immunostaining. Results were confirmed in vitro using podocytes on which C3aR1 was silenced and in vivo using THSD7A induced MN in balb/c mice. RESULTS: Following exposure to sera from MN patients, we have confirmed deposition of human lgG on podocytes and formation of MAC complex, accompanied by albumin leakage. MAC inhibition did not prevent albumin leakage while GOAC supplemented with C3aR1 antagonists as well as GOAC using podocytes in which C3aR1 was silenced were able to prevent glomerular filtration damage and albumin leakage. Efficacy of C3aR1 antagonists in preventing proteinuria was confirmed in vivo, substantiating our findings. CONCLUSIONS: We have successfully developed a glomerulus-on-a-chip system that closely mimics the GFB structure and provides a powerful tool for studying renal regenerative and disease mechanisms in proteinuric diseases. Using a combination of in vitro and in vivo models, we showed that C3a/C3aR signaling plays a dominant role in complement-mediated MN pathogenesis. Source of Funding: GOFARR Fund NIH NIDDK RO1 © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e361 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Qi Zhang More articles by this author Paolo Cravedi More articles by this author Astgik Petrosyan More articles by this author Valentina Villani More articles by this author Roger De Filippo More articles by this author Laura Perin More articles by this author Stefano Da Sacco More articles by this author Expand All Advertisement PDF DownloadLoading ...