Introduction

Urine is a good biofluid to obtain non-invasively for health check and medical examination. Many trials have been done to find biomarkers in urine by proteomics and to apply the biomarker detection to clinic. For the purpose, we have been collecting urine samples from healthy volunteers and patients since 2013. In this presentation, we will introduce the numbers of samples in our urine bank in Biofluid Biomarker Center (BBC), Niigata University, Japan and how to select urine samples for proteomic analysis.

Methods

Urine samples have been collected at several hospitals and facilities according to the guideline for urine collection proposed from HUPO Kidney and Urine Proteome Project Initiative and stored in freezers at BBC http://www.hkupp.org/Urine%20collectiion%20Documents.htm). The number of peoples who donated urine is more than 15.000 and the number of urine samples is more than 160.000, indicating more than 10 urine samples have been collected serially from a person for several years. In this presentation, we focused on urine samples from diabetic patients who might develop kidney impairment detected by microalbuminuria/proteinuria and decrease of the glomerular filtration rate (GFR) during urine collection,

Results

In BBC urine bank, 105,592 urine samples have been collected from 8,346 diabetic patients. Among them, 3,353 patients were in good GFR (>60 ml/min) in 2018 and were followed for 5 years to the present. The patients who still keep the good GFR was 2,760 (82.3%) but the others (17.7%) had decline of the GFR in these 5 years. In addition, 2,777 (61.1%) patients out of 3,353 had no microabluminuria or proteinuria in 2018, but 1,081 (38.9%) patients developed microabluminuria or proteinuria. These urine samples may be used to find1by quantitative proteomics.

Conclusion

We have collected a world largest number of urine samples from various disease patients in BBC for more than 5 years. These urine collection may be useful for discovery of urine biomarkers to predict or find diseases in early stages.