Abstract: TH-PO565
Urinary Exosomes as Noninvasive Window to Glomerular and Tubular Cells and Their Communication
Session Information
- Glomerular Diseases: Omics, Biomarkers, and Tools
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: Mechanisms, including Podocyte Biology
Authors
- Thiagarajan, Sindhu, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Kern, Janina, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Sopel, Nina, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Müller-Deile, Janina, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
Background
Although many renal diseases originate in glomerular unit, subsequent damage of tubular cells may lead to alleviate the disease condition. Exosomes are a type of extracellular vesicles, which play a major role in intercellular communication in many diseases. All cells secrete exosomes which carry nucleic acids, proteins, lipids and metabolites to recipient cells. Our previous studies showed the role of microRNAs in intraglomerular communication as well as their disease specific detection in the urine. However, little is known if such communication can be mediated by exosomes and if they also can serve as non-invasive biomarker.
Methods
Characterization of exosomes from the glomerular and tubular cell lines and patients’ urines was performed via nanoparticle tracking analysis to identify size and concentration, electron-microscopic imaging to show intact morphology and appropriate size of the exosomes as well as FACS staining and western blotting to detect common exosome markers. Proteome profiling and proteases activity assay of exosomes from cell culture supernatant and respective “mother cells“ was used to characterize internal and external exosome cargo. Cell type specific marker in FACS sorting of exosomes was used to identify the cellular origin of urinary exosomes.
Results
Cell culture and urinary derived extracellular vesicles showed typical exosome size, morphology and marker expression (CD63, CD9, CD81). Proteomics of cell culture derived exosomes and mother cells allowed distinct protein cargo characterization of the exosomes. Proteases activity could be detected on exosome surface derived from glomerular cells. Glomerular cell derived exosomes could be detected and isolated via cell sorting from urines of patients with different glomerular diseases giving a non-invasive material for further characterization as potential biomarker.
Conclusion
Podocyte derived exosomes might deliver cargo to tubular cells on their way of being secreted with the urine where they might serve as non-invasive snapshots of their cell of origin. Size wise exosomes should not be able to pass the glomerular basement membrane in vivo. However, the presence of proteases on exosomes might enable the passage of endothelial cell or even systemic exosomes through the GBM to reach podocytes or even tubular cells.
Funding
- Government Support – Non-U.S.