Abstract: TH-PO775
Single-Cell Transcriptional Analysis Reveals the Effect of Anti-PLA2R and Anti-THSD7A Sera on Human Glomerular Cells
Session Information
- Glomerular Diseases: Podocyte Biology - I
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1403 Podocyte Biology
Authors
- Da Sacco, Stefano, Children's Hospital Los Angeles, Los Angeles, California, United States
- Zhang, Qi, Children's Hospital Los Angeles, Los Angeles, California, United States
- Vink-van Setten, Coralien, Radboud Universiteit, Nijmegen, Gelderland, Netherlands
- Wetzels, Jack F., Radboud Universiteit, Nijmegen, Gelderland, Netherlands
- Cravedi, Paolo, Icahn School of Medicine at Mount Sinai, New York, New York, 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 due to the deposition of anti-podocyte antibodies in the glomerular subepithelial space. Several podocyte proteins have been identified as targets of these autoantibodies, with PLA2R and THSD7A the most prominent. We investigated the specific effect of anti-PLA2R and anti-THSD7A on glomerular cells using single cell transcriptomics on a human glomerulus-on-a-chip (GOAC) system.
Methods
GOACs were generated using human primary podocytes and glomerular endothelial cells and cultured with human serum from MN patient with anti-PLA2R or anti-THSD7A antibodies for 72 hours. Sera from healthy individuals were used as a control. Samples from three different individuals were used for each group. Albumin leakage assay was performed on GOAC to confirm injury. Single cell RNA-seq analysis (scRNA-seq) was performed on cells retrieved from the GOAC. Downstream analyses were done using UMAP, gene and pathway enrichment, and intra- and inter-cluster comparative transcriptomics.
Results
Exposure to anti-PLA2R and anti-THSD7A sera from MN patients induced injury on the GOAC as confirmed by albumin leakage. scRNA-seq analysis showed robust activation of the complement pathway in both cohorts. Preliminary analysis also suggested activation of podocyte injury pathways with changes in genes involved in slit diaphragm formation being more prominent in cells exposed to anti-THSD7A sera vs the anti-PLA2R. At the same time, GEC displayed an enrichment in genes involved in proliferation and metabolic changes under both conditions compared to healthy sera, suggesting a broader effect of MN sera that extends beyond direct podocyte damage.
Conclusion
The combined use of the GOAC and transcriptomics studies allows to investigate molecular and transcriptional changes affecting podocytes and GEC when both exposed to MN sera. This approach can help unraveling glomerular mechanisms of injury in MN, thus providing potential new targets for the treatment of nephropathies and other glomerular diseases.
Funding
- NIDDK Support