ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Please note that you are viewing an archived section from 2023 and some content may be unavailable. To unlock all content for 2023, please visit the archives.

Abstract: FR-PO1063

Identification of Surrogate Biomarkers Reflecting Tubular Failed Repair in CKD

Session Information

Category: CKD (Non-Dialysis)

  • 2303 CKD (Non-Dialysis): Mechanisms

Authors

  • Bohnenpoll, Tobias, Evotec International GmbH, Göttingen, Germany
  • Lo, I-Ju, Evotec International GmbH, Göttingen, Germany
  • Ragan, Seamus, Chinook Therapeutics Inc, Seattle, Washington, United States
  • Badal, Shawn S., Chinook Therapeutics Inc, Seattle, Washington, United States
  • Radresa, Olivier, Evotec International GmbH, Göttingen, Germany
  • Kuo, Jay, Chinook Therapeutics Inc, Seattle, Washington, United States
  • Cox, Jennifer H., Chinook Therapeutics Inc, Seattle, Washington, United States
  • Andag, Uwe, Evotec International GmbH, Göttingen, Germany
  • King, Andrew J., Chinook Therapeutics Inc, Seattle, Washington, United States
  • Olson, N. Eric, Chinook Therapeutics Inc, Seattle, Washington, United States
Background

Interstitial fibrosis, tubular atrophy and inflammation (IFTA) are common final pathways to end-stage kidney disease (ESKD), contributing to progressive nephron loss and functional decline in most chronic kidney diseases (CKD), including those typically glomerular in origin. Disease-associated failed repair proximal tubule cells (FR-PTs) have been described in rodent models and are characterized by a proinflammatory and profibrotic phenotype that contributes to IFTA severity. We have recently demonstrated that accumulation of FR-PTs in humans predicts reduced event-free survival in multiple CKD etiologies. Here we used multi-omics analysis of patient-matched kidney biopsies and biofluids from the NURTuRE CKD cohort to discover biomarkers associated with an accumulation of FR-PTs to non-invasively identify patients at risk for progression.

Methods

Serum (n = 99) and urine samples (n = 22) from multiple etiologies from the NURTuRE biobank were assayed using Olink and SomaScan proteomics platforms, respectively. Patient-matched kidney biopsies for each of the samples were analyzed via RNA-Seq and scored for a gene signature reflecting FR-PTs. Correlation analysis of biofluid protein abundance with kidney mRNA expression and FR-PTs signature scores suggested candidate non-invasive biomarkers for further validation (r ≥ 0.4 and p ≤ 0.05).

Results

Proteomic analysis identified 78 serum and 79 urine proteins significantly correlated with the kidney biopsy FR-PT score in CKD patients. Strong positive correlation of 14/78 serum and 9/79 urine proteins with kidney mRNA expression suggests these proteins originate from the kidney or share a common regulatory mechanism. Importantly, expression of the respective genes was negatively correlated with eGFR and enriched in FR-PTs and immune cells, likely reflecting the kidney inflammatory and fibrotic microenvironment.

Conclusion

This study identified potential surrogate biomarkers associated with the accumulation of FR-PTs in subjects with different CKD etiologies from the NURTuRE cohort. These may aid in identifying patients with a disease-relevant phenotype and at risk for progression and will complement our target identification and validation focused on maladaptive tubular repair.

Funding

  • Commercial Support – Chinook Therapeutics, Evotec SE