Single extracellular vesicles protein profiling classifies renal fibrosis stages in mice model

Renal fibrosis is a common consequence of various chronic kidney diseases (CKD), leading to the loss of renal function and even end-stage renal failure. Extracellular vesicles (EVs) were shown to be involved in development of CKD and renal fibrosis. In this study, we induced renal fibrosis in mice model through unilateral ureteral obstruction (UUO) and extracted EVs from the kidney with induced fibrosis. Proximity barcoding assay (PBA) was performed to detect the expression of 112 proteins at individual EVs level for renal fibrosis of Grade I to IV and sham control group as well. The single EVs are classified into subpopulations according to the surface proteomic characteristics. We discovered several EV subpopulations, with presence of ITGAM, ITGA6, CD73, CD13 and ALDH1, increase significantly with development of renal fibrosis. These findings indicate that besides protein expression, proteomic fingerprints of single EVs can be potential biomarkers for surveillance of CKD and renal fibrosis.