Journal
KIDNEY INTERNATIONAL
Volume 85, Issue 5, Pages 1225-1237Publisher
ELSEVIER SCIENCE INC
DOI: 10.1038/ki.2013.422
Keywords
actin cytoskeleton; exosome; glomerular disease; podocyte; proteomics; Q-exactive mass spectrometer
Categories
Funding
- NIH [1RC1DK086161-01]
- NIDDK [P30 DK090728]
- NephCure Foundation
- David Woods Kemper Memorial Foundation
- Mayo Clinic College of Medicine
- [10266762]
Ask authors/readers for more resources
Urinary exosome-like vesicles (ELVs) are a heterogenous mixture (diameter 40-200 nm) containing vesicles shed from all segments of the nephron including glomerular podocytes. Contamination with Tamm-Horsfall protein (THP) oligomers has hampered their isolation and proteomic analysis. Here we improved ELV isolation protocols employing density centrifugation to remove THP and albumin, and isolated a glomerular membranous vesicle (GMV)-enriched subfraction from 7 individuals identifying 1830 proteins and in 3 patients with glomerular disease identifying 5657 unique proteins. The GMV fraction was composed of podocin/podocalyxin-positive irregularly shaped membranous vesicles and podocin/ podocalyxin-negative classical exosomes. Ingenuity pathway analysis identified integrin, actin cytoskeleton, and Rho GDI signaling in the top three canonical represented signaling pathways and 19 other proteins associated with inherited glomerular diseases. The GMVs are of podocyte origin and the density gradient technique allowed isolation in a reproducible manner. We show many nephrotic syndrome proteins, proteases, and complement proteins involved in glomerular disease are in GMVs and some were only shed in the disease state (nephrin, TRPC6, INF2 and phospholipase A(2) receptor). We calculated sample sizes required to identify new glomerular disease biomarkers, expand the ELV proteome, and provide a reference proteome in a database that may prove useful in the search for biomarkers of glomerular disease.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available