Raby, Katie Louise; (2020) Urinary exosomes protein cargo as biomarkers of Autosomal Dominant Polycystic Kidney Disease (ADPKD). Doctoral thesis (Ph.D), UCL (University College London).

Preview

Text Raby_10090265_Thesis_Appendix_redacted.pdf Download (22MB) | Preview

Abstract

ADPKD is the most common genetic renal disease and affects 1:1000 people worldwide with highly variable rates of progression to end-stage renal disease (ESRD). While 50% of patients (PKD1 mutation) will reach ESRD at an average age of 53 years, it is not possible to predict individual rates of progression. There is an unmet clinical need for reliable biomarkers of disease progression. One potential source of biomarkers is exosomes, small vesicles released via the endosomal pathway into the extracellular space and body fluids including urine, in both healthy and diseased states. Exosomes reflect their cell of origin and contain a subset of proteins and RNAs which have been shown to play a role in biological processes and provide the potential to be prognostic markers of disease and severity. Using urine collected from ADPKD patients over a 5-year period stored in 5ml aliquots, a protocol was optimised for the isolation of urinary exosomes (UEX) from small volumes. UEX yield, purity and size were validated using nanoparticle tracking analysis, transmission electron microscopy, immunoblotting and FACS of exosome membrane markers. Liquid-chromatography tandem-mass-spectrometry of UEX proteins revealed differences in expression between: i) normal healthy controls and ADPKD patients; ii) ADPKD patients at different CKD stage; iii) patients with rapid or slow disease progression regardless of renal function at clinical presentation; and, iv) patients with poor, delayed or good responses to Tolvaptan©. In vitro experiments investigated the potential role of exosomes in promoting a disease phenotype by assessing functional changes in exosome-treated normal and ADPKD renal epithelial cells. The intracellular distribution of exosomes was assessed by confocal microscopy providing insight into the uptake of exosomes into normal and ADPKD cells. Taken together the data show an important role for UEX proteins as prognostic markers of ADPKD progression and for monitoring of Tolvaptan efficacy and suggest a role for exosomes in intercellular communication in this disease.

Download activity - last month

Export as JSONXMLCSV

Download activity - last 12 months

Export as JSONCSVXML

Downloads by country - last 12 months

Export as XMLCSVJSON

Archive Staff Only

View Item