ASN's Mission

ASN leads the fight to prevent, treat, and cure kidney diseases throughout the world by educating health professionals and scientists, advancing research and innovation, communicating new knowledge, and advocating for the highest quality care for patients.

learn more

Contact ASN

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

email@asn-online.org

202-640-4660

The Latest on Twitter

Kidney Week

Abstract: FR-PO1126

A Proteomic Atlas Depicting the Changes in Small Urinary Extracellular Vesicles Throughout Kidney Transplantation

Session Information

  • Transplantation: Basic
    November 08, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
    Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

  • 1901 Transplantation: Basic

Authors

  • Braun, Fabian, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
  • Rinschen, Markus M., The Scripps Research Institute, La Jolla, United States
  • Buchner, Denise, University of Cologne, Cologne, Germany
  • Bohl, Katrin, University of Cologne, Cologne, Germany
  • Plagmann, Ingo, University of Cologne, Cologne, Germany
  • Schermer, Bernhard, University of Cologne, Cologne, Germany
  • Beyer, Andreas, University of Cologne, Cologne, Germany
  • Benzing, Thomas, University of Cologne, Cologne, Germany
  • Wahba, Roger, University of Cologne, Cologne, Germany
  • Stippel, Dirk L., University of Cologne, Cologne, Germany
  • Kurschat, Christine E., University of Cologne, Cologne, Germany
  • Mueller, Roman-Ulrich, University of Cologne, Cologne, Germany
Background

Extracellular vesicles (EVs) have come into the research focus of many life sciences. Urinary EVs, specifically since they can be collected noninvasively, hold the prospect of harboring valuable biomarkers to complement renal biopsies. We aimed to establish a concise atlas of the urinary EV protein content and its changes during living donor transplantation as a resource for the investigation of biological processes and biomarker identification.

Methods

We employed a protocol of differential highspeed- and ultracentrifugation for the separation of small urinary EVs (suEVs) of 22 recipient-donor pairs collected on day -1 (donor sample), 0, 1 as well as 3 and 12 months after transplantation (recipient samples). Quantitative mass spectrometry was used to detect the suEV proteome with subsequent GO analysis to define the involved and changing biological processes. We used linear regression models to correlate the proteomic data set with transplant function 6 and 12 months after transplantation. The resulting candidate proteins were validated in a targeted proteomic analysis of additional 22 recipient-donor pairs sets.

Results

More than 1700 unique proteins were identified in ≥50% of the initial sample set. The single samples depicted a clear clustering by time point of urine collection with specific proteomic time course patterns apparent over the course of transplantation when analyzing the mean protein intensities per time point. Specifically, we detected a decrease in membrane trafficking and increased complement components directly after transplantation. Linear regression models identified a list of 64 candidate proteins with a correlative potential for renal function (eGFR) 6 and 12 months after transplantation. The performed validation experiments showed the abundance of one protein - PEPCK – to be a potential predictor of allograft eGFR after 12 months.

Conclusion

We present the first concise atlas of the changes in the human suEV proteome throughout living donor kidney transplantation. This data set serves as a valuable resource for the investigation of both the biological processes affected by renal transplantation and the identification of potential biomarkers as indicated by our first correlation analyses.

Funding

  • Government Support - Non-U.S.