Abstract: SA-OR050
A Human Model of Membranous Nephropathy on-a-Chip
Session Information
- Glomerular Diseases: Technologies, Mechanisms, and Therapeutics
November 09, 2019 | Location: 201, Walter E. Washington Convention Center
Abstract Time: 04:54 PM - 05:06 PM
Category: Glomerular Diseases
- 1204 Podocyte Biology
Authors
- Da Sacco, Stefano, Children's Hospital Los Angeles, Los Angeles, California, United States
- Petrosyan, Astgik, Children's Hospital Los Angeles, Los Angeles, California, United States
- Cravedi, Paolo, Mount Sinai Nephrology, Pianoro, BOLOGNA, Italy
- Villani, Valentina, Children's Hospital Los Angeles, Los Angeles, California, United States
- Angeletti, Andrea, Mount Sinai Nephrology, Pianoro, BOLOGNA, Italy
- Manrique, Joaquin, Complejo Hospital de Navarra, Pamplona, Spain
- De Filippo, Roger E., Children's Hospital Los Angeles, Los Angeles, California, United States
- Perin, Laura, Children's Hospital Los Angeles, Los Angeles, California, United States
Background
Primary membranous nephropathy (MN) is a leading cause of nephrotic syndrome in adults worldwide. MN pathogenesis involves the deposition of auto-antibodies against podocyte-expressed antigens in the glomerular subepithelial space, causing podocyte injury and initiating progressive renal damage which leads to kidney failure in approximately one third of patients. While the role of complement has been confirmed, many questions are still unanswered and the study of mechanisms responsible for MN pathogenesis is challenged by the lack of in vitro systems that recapitulate human disease.
Methods
We have developed a novel glomerulus-on-a-chip system (GOAC) using primary, immortalized and amniotic fluid derived podocytes together with glomerular endothelial cells (GEC) in combination with OrganoPlates and assessed the functional response to human MN serum. Human podocytes were seeded on microfluidic chips with human GEC. Immunofluorescence and WB were performed for podocyte, endothelial and GBM markers. Barrier selective-permeability was investigated. Chips were cultured with serum from MN patients or healthy individuals. Functional response was assessed by albumin permeability assay. IgG/IgG4 deposition was assessed by immunofluorescence while mechanisms of action were explored by Western Blotting and immunostaining.
Results
This system recapitulates salient characteristics and functions of the in vivo glomerular filtration barrier. The GOAC is permeable to inulin and impermeable to albumin. When exposed to serum of subjects affected by MN, the chip displayed deposition of IgG and complement C3 on podocytes and loss of permselectivity to albumin to an extent correlated to urinary protein loss in respective patients. Moreover, we have found evidence suggesting that activation of ILK/MAPK/SNAIL signaling pathway in podocytes might contribute to injury during MN pathogenesis.
Conclusion
We have successfully developed a glomerulus-on-a-chip system that closely mimics the GFB structure and provides a powerful tool for studying pathophysiology of MN. This system will increase our ability to individualize treatments and facilitate drug discovery, thus ultimately benefiting patients affected by this and potentially other glomerular diseases.
Funding
- Private Foundation Support