Abstract: SA-PO690
Recapitulating Shiga Toxin-Mediated Renal Injury in Engineered Microvessels
Session Information
- Pediatric Glomerular Disease
November 09, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pediatric Nephrology
- 1700 Pediatric Nephrology
Authors
- Whelan, Russell S., Seattle Children''s Hospital, Seattle, Washington, United States
- Himmelfarb, Jonathan, Kidney Research Institute, Seattle, Washington, United States
- Zheng, Ying, University of Washington, Seattle, Washington, United States
Background
Hemolytic-Uremic Syndrome (HUS) presents as a severe form of thrombotic microangiopathy (TMA), and the endothelial injuries that precipitate HUS/TMA are caused by a wide range of insults, including metabolic, immunologic, pharmacologic, and infection-associated etiologies. Shigatoxin-producing E. Coli HUS (STEC-HUS) is an infectious TMA that results in renal injury, leading to AKI, permanent renal damage and death, and is the leading cause of dialysis initiation in otherwise healthy children. Despite severe long-term consequences with STEC-HUS, no targeted therapies to-date have demonstrated any clinical benefit. Use of perfusable vascular models previously developed in our lab provide physiologically relevant platforms to evaluate specific cellular injury mechanisms responsible for the endothelial injury in STEC-HUS. These models also provide a well-controlled and efficient platform for evaluating novel therapeutic interventions.
Methods
Human primary renal endothelial cells were treated with Stx1 and Stx2, the principal toxins responsible for STEC-HUS, and evaluated for cell death, cell injury, and morphology. Studies were performed in both 2D tissue culture and 3D microvessel platforms.
Results
Treatment of isolated human primary renal endothelial cells with either Stx1 or Stx2 demonstrated effective binding, toxin internalization and death. Significant increases in both apoptosis and necrosis were appreciated in a dose-dependent manner in these microvascular cells, with non-renal endothelial cell lines demonstrating insensitivity to Stx1 or Stx2 treatment at equivalent or higher doses. Engineered microvessels using primary renal endothelial cells were generated and maintained under flow for several days. In these models, treatment with Stx1 and Stx2 demonstrated effective binding to luminal endothelia, with evidence of a greater degree of endothelial injury and endothelial denudation observed with Stx2 than Stx1.
Conclusion
Human primary renal endothelial cells exhibit dose-specific responses to Shigatoxin consistent with clinical presentation of STEC-HUS. Notably, engineered renal microvessels also exhibited endothelial injury consistent with Shigatoxin toxicity. Ongoing phenotypic and transcriptional studies will use these models to delineate the specific injury pathways responsible for endothelial injury that result in vascular damage and progression to TMA.
Funding
- NIDDK Support