Related Experiment Video
Updated: Feb 6, 2026

A Standardized Liquid Biopsy Preanalytical Protocol for Downstream Circulating-Free DNA Applications
Published on: September 16, 2022
Liquid biopsy biomarkers of renal interstitial fibrosis based on urinary exosome
Lv Chun-Yan1, Zhao Zi-Yi1, Yang Tian-Lin1
1Affiliated Hospital of Chengdu University of T. C. M./Clinical Medical College, Chengdu University of T. C. M., Chengdu 610072, China.
Abstract:
Renal interstitial fibrosis (RIF) is difficult to diagnose. This paper explored liquid biopsy markers in urinary exosomes derived from RIF patients. Urine samples from 32 patients with various degrees of RIF and 20 non-RIF patients were collected. The size and morphology of urinary exosomes isolated by polyethylene glycol were observed with electron microscopy. Protein biomakers of exosomes were analyzed by Western blot. qRT-PCR was used to detect the levels of biomarkers (miR-29c, miR-21, E-cadherin, and vimentin) of epithelial mesenchymal transition in urinary exosomes. The diagnostic value was detected with ROC curves. Results displayed successfully isolated urinary exosomes. The examined miRNAs and mRNAs were checked from all urinary exosomes samples, except for two cases of RIF which lacked E-cadherin mRNA. RNA levels were different in patients with diverse degrees of RIF. Urinary miR-29c was decreased with the progress of fibrosis. Levels of E-cadherin mRNA were first decreased and then increased. The contents of miR-21 and vimentin mRNA were also depended on the degrees of RIF. ROC curve analysis showed that the area under the curve (AUC) of miR-29c was 0.8621, statistically significant compared with the non-RIF group (P < 0.05). The miR-29c level within the urinary exosomes is a promising marker for the diagnosis of RIF.
Related Concept Videos
Renal Regulation of Acid-Base Balance
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...
Cystic Fibrosis: Pathogenesis
CF is primarily caused by a genetic mutation in a chromosome 7 gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The most common gene mutation leading to CF is the ΔF508 mutation,...
Overview of Exosomes
Stahl et al. discovered exosomes in 1983, but the exosomes were initially considered waste products released from the...
Introduction to Urinary System
The kidneys are bean-shaped organs located in the retroperitoneal space, on either side of the vertebral column, between the T12 and L3 vertebrae. They are partially protected by the rib cage and surrounded by perirenal fat, which provides cushioning. They are responsible for urine formation and play critical roles in regulating blood pressure, electrolyte levels, and hormone production. The ureters...
Urinary Bladder
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...
Disorders of the Urinary System
Urinary tract infections (UTIs) are one of the most common urinary system disorders. They are caused by bacteria that enter the urethra and can spread to the bladder resulting in cystitis. Pyelonephritis is the result of a UTI that has ascended to the level of the...

