Abstract: TH-PO0352
Identification of Functional Minicollagen EMB-9 Constructs in Caenorhabditis elegans for Adeno-Associated Virus-Based Gene Therapy Approaches to Alport Syndrome
Session Information
- Glomerular Diseases: Genetics to Therapeutics
October 22, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: Mechanisms, including Podocyte Biology
Authors
- Ganga, Anil Kumar, Duke University, Durham, North Carolina, United States
- Su, Caitlin Y., Duke University, Durham, North Carolina, United States
- Chi, Qiuyi, Duke University, Durham, North Carolina, United States
- Goncalves, Kevin A., Deerfield Management Company LP, New York, New York, United States
- Steinsapir, Andrew, Deerfield Management Company LP, New York, New York, United States
- Lennon, Rachel, The University of Manchester, Manchester, England, United Kingdom
- Sherwood, David R., Duke University, Durham, North Carolina, United States
Group or Team Name
- Sherwood Lab
Background
Type IV collagen networks between podocyte and endothelial cells in the kidney glomerular basement membrane (GBM) are essential for proper kidney filtration. Mutations in type IV collagen genes that impair or prevent type IV collagen heterotrimer formation lead to Alport syndrome, a hereditary disease characterized by defects in the GBM and progressive renal dysfunction. Although current treatments can slow disease progression, curative therapies are not available. Therefore, gene therapy is a promising therapeutic approach for Alport syndrome. However, the large size of type IV collagen genes exceeds the adeno-associated virus (AAV) payload limit. Thus, there is a critical need to identify smaller collagen constructs that can be efficiently delivered through AAV and restore kidney basement membrane function.
Methods
Toward this goal, we used Caenorhabditis elegans as a rapid animal model system establish the secretion, localization, and function of mini collagens. We generated several truncated constructs based on EMB-9, the C. elegans ortholog of human type IV collagen α1 chains. Each construct was C-terminally fused to mRuby2 and introduced into worms to generate transgenic lines. To evaluate whether these constructs restore BM defects, we utilized the C. elegans utse-seam basement membrane-basement membrane (BM-BM) linkage as a model, which has similarities to the fused BM-BM at the kidney GBM. The Utse-seam BM-BM linkage maintains the uterus during egg laying and defects in this connection lead to a uterine rupture phenotype. We introduced mRuby2 tagged mini-collagen constructs into worms expressing endogenous EMB-9 tagged with mNeonGreen (mNG). Using mNG-targeting RNAi to deplete endogenous EMB-9, we assessed functional rescue.
Results
We discovered, using fluorescence microscopy, that several truncated mini-collagen proteins were successfully secreted and localized to the basement membrane (BM) using fluorescence microscopy. Using mNG-targeting RNAi to deplete endogenous EMB-9, we assessed functional rescue. Through this screen, we have thus far identified one construct that partially rescues the rupture phenotype.
Conclusion
Overall, our findings demonstrate that C. elegans provides a rapid in vivo platform for evaluating and prioritizing mini-collagen gene therapy constructs for BM diseases such as Alport syndrome.
Funding
- Commercial Support – Deerfield Management