Abstract: FR-PO1009

Non-Invasive Proteomics to Detect Biomarkers for Kidney Allograft Dysfunction

Session Information

Category: Transplantation

  • 1701 Transplantation: Basic and Experimental

Authors

  • Watson, Maura A., Walter Reed National Military Medical Center, Vienna, Virginia, United States
  • Srivastava, Meera, USU School of Medicine, Bethesda, Maryland, United States
  • Little, Dustin J., AstraZeneca, Gaithersburg, Maryland, United States
  • Eidelman, Ofer, Uniformed Services University of the Health Sciences , Bethesda, MD, Maryland, United States
  • Nee, Robert, Walter Reed National Military Medical Center, Vienna, Virginia, United States
  • Bera, Alakesh, Uniformed Services University, Bethesda, Maryland, United States
  • Oliver, David K, Walter Reed National Military Medical Center, Vienna, Virginia, United States
  • Pollard, Harvey, Uniformed Services University of the Health Sciences , Bethesda, MD, Maryland, United States
  • Jindal, Rahul M., Uniformed Services University of Health Sciences, SILVER SPRING, Maryland, United States
Background

Non-invasive biomarkers are needed for monitoring patients with transplant-associated renal injury to predict early acute rejection (AR). Currently, invasive allograft biopsy is required to make a definitive diagnosis of AR. We hypothesized that protein biomarkers released from rejecting allograft tissues can be detected early in the systemic circulation.

Methods

Serum from healthy individuals, transplant patients with either stable allograft function or chronic kidney disease (CKD), transplant patients requiring kidney biopsy, and CKD patients awaiting transplant (25 patients per category) were labeled with the fluorescent dye Cy3, and assayed on 1275 feature phosphoprotein microarray platform from Fullmoon biosystems. We validated these biomarkers associated with disease severity using a quantitative Reverse Capture Protein Microarray (RCPM) platform. Serum samples were spotted individually in serial dilutions and probed with a specific antibody predicted by the antibody microarray platform.

Results

Bioinformatic analysis compared healthy individuals, pre and post-transplant CKD patients and identified proteins that were present in higher serum concentrations in pre-transplant CKD and transplant allograft rejected patients. These included ATM, p38MAPK, HDAC8, SAPK/JNK, GSK3a-b, NFkappa B and RelB which pointed to an affected p53 signaling pathway. Among the tested phosphorylated proteins, phospho-species of SAPK/JNK and RelB were elevated in stable allograft function compared with CKD pre-transplant and graft rejected serum.

Conclusion

These novel serum analytes, together or independently, may constitute a robust and quantitative serum proteomic signature for AR in renal allografts. Detection of kidney allograft AR by affinity proteomics offers a promising non-invasive tool for surveillance of transplant recipients and for guiding treatment of graft rejection.

The views expressed are the authors and do not reflect official policy of the Department of Army/Navy/Air Force, Department of Defense, or U.S. Government.

Funding

  • Other U.S. Government Support