One of the primary causes for untimely loss of organ transplants is the inability to recognize immune injury from acute rejection early, resulting in considerable injury and irreversible loss of function of the organ. With the increasing gap between available organs and patients with end stage kidney disease awaiting organ transplants, and the only mechanism of definitely classifying organ injury being dependent on an invasive biopsy, improved methods for early and non-invasive detection of transplant injury is a critical unmet need. This is an application for renewal of an existing RO1, which conducted human urine proteomic studies by sophisticated mass spectrometric and bioinformatic techniques in 396 pediatric and adult kidney transplant recipients, and resulting in the identification of a 33 urine protein panel that classifies acute rejection, chronic rejection and vral inflammation from BK virus infection, with >80% accuracy by a non-invasive urine protein assay. With expertise in clinical trial design, urine sample acquisition and processing from multiple clinical sites, clinical database design, access to archived, highly annotated samples from 600 kidney transplant recipients, access to serial urine samples from two randomized clinical trials and deep expertise in biostatistics, this mature team of investigators now propose to use these selected proteins to generate a transplant injury atlas in the renal transplant biopsy by a novel multiplex immunofluorescence/ in situ hybridization (miFish) assay (Aim 1) and to interrogate the clinical utility of the 33 urine proteins by a customized multiplex MSD- ELISA assay (Aim 2) for prediction of rejection and infection specific transplant injury, accurate staging of rejection and to evaluate these biomarkers as surrogate outcome measures of therapy. The benefit of this research would be to move urine protein non-invasive markers for clinical evaluation of graft rejection ready for out-patient clinical application avoid biopsies and individualize immunosuppression, while avoiding rejection, thus supporting the application of predictive, personalized and precision medicine for the kidney transplant recipient.

Public Health Relevance

There is a critical unmet need for improved monitoring of organ transplant recipients. Current diagnosis of transplant injury is based on the non-specific rise in the serum creatinine, which triggers an invasive biopsy, subject to variations in histological interpretation. We have identified key urine proteins that diagnose transplant injury non-invasively and define different types of injury, inclusive of acute rejection. These urine proteins will be further evaluated for their biological relevance in the organ and will be evaluate for their clinical utility as a non-invasive assay for early diagnosis and prediction of injury in enal transplant recipients, avoiding

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
High Priority, Short Term Project Award (R56)
Project #
2R56DK083447-07A1
Application #
9132405
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Flessner, Michael Francis
Project Start
2009-07-01
Project End
2016-08-31
Budget Start
2015-09-20
Budget End
2016-08-31
Support Year
7
Fiscal Year
2015
Total Cost
Indirect Cost
Name
University of California San Francisco
Department
Surgery
Type
Schools of Medicine
DUNS #
094878337
City
San Francisco
State
CA
Country
United States
Zip Code
94118
Sigdel, Tara K; Gao, Yuqian; He, Jintang et al. (2016) Mining the human urine proteome for monitoring renal transplant injury. Kidney Int 89:1244-52
Yang, Joshua Young Cynming; Sigdel, Tara K; Sarwal, Minnie M (2016) Self-antigens and rejection: a proteomic analysis. Curr Opin Organ Transplant 21:362-7
Nasr, Michael; Sigdel, Tara; Sarwal, Minnie (2016) Advances in diagnostics for transplant rejection. Expert Rev Mol Diagn 16:1121-1132
Delville, Marianne; Sigdel, Tara K; Wei, Changli et al. (2014) A circulating antibody panel for pretransplant prediction of FSGS recurrence after kidney transplantation. Sci Transl Med 6:256ra136