Abstract: FR-PO873
Single-Cell Transcriptomics Tracking the Evolution of Cell and Gene Expression in Blood and Urine Cells of a Patient with IgA Nephropathy before, during, and after Therapy
Session Information
- IgA Nephropathy: Clinical, Outcomes, and Therapeutics
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Schena, Francesco Paolo, Universita degli Studi di Bari Aldo Moro, Bari, Puglia, Italy
- Limardo, Monica, ASST-Lecco, Lecco, Italy
- D'Aliberti, Deborah, Universita degli Studi di Milano-Bicocca, Milano, Italy
- Spinelli, Silvia, Universita degli Studi di Milano-Bicocca, Milano, Italy
- Piazza, Rocco, Universita degli Studi di Milano-Bicocca, Milano, Italy
- L'Imperio, Vincenzo, Universita degli Studi di Milano-Bicocca, Milano, Italy
- Cox, Sharon N., Universita degli Studi di Bari Aldo Moro, Bari, Puglia, Italy
Background
Longitudinal studies on IgAN patients with active renal lesions at an early stage of the disease using parallel single-cell transcriptomics (scRNA) during therapeutic intervention have never been conducted. Our objective was to investigate transcriptomic variations at a single-cell level in PBMCs and urinary cells before, during, and after therapy.
Methods
The IgAN patient with active renal lesions (E1,C1 ) was followed up for one year after undergoing 4 months of pulse and oral corticosteroids and supportive therapy. PBMCs and urinary cells were collected at baseline, during therapy (at the 2nd and 4th month), and after 4 months. Cells were processed using a Chromium 10x platform. Libraries were obtained with a Single Cell 3' Kit followed by sequencing on a Novaseq 6000. Data analysis included read processing with Cell Ranger v. 7.1.0 and Seurat v. 5.0. Unique Molecular Identifiers were regressed out, followed by PCA for dimensionality reduction. UMAP was applied for further reduction and cluster identification using FindNeighbors and FindClusters algorithms. SingleR was used for cell type identification, followed by manual curation. Differentially expressed genes were obtained comparing scRNA profile obtained from 2 healthy control donors using Wilcoxon nonparametric tests.
Results
Laboratory data revealed stable eGFR and progressive reduction of proteinuria (from 1.5 g to 0.2 g/day) after 1 year. scRNA data analysis showed significant transcriptional changes in IgAN, particularly affecting genes associated with B and T cell receptors, as well as the complement cascade. An inversion of the CD4/CD8 ratio and increase in the monocytic fraction were found. Specific changes in gene expression and cell type composition were noted upon treatment and ongoing analysis is evaluating the effect of corticosteroids on urinary cells.
Conclusion
Transcriptional and cell type composition changes were found in PBMCs at a single cell resolution in IgAN, particularly demonstrating specific alterations during corticosteroid therapy.
Funding
- Government Support – Non-U.S.