Regeneration and Diagnosis of Kidney Disease Using Exosomes

A growing global prevalence of acute kidney injury (AKI) and chronic kidney disease (CKD), high costs of kidney transplantation, a shortage of kidney donors, and low survival rate after dialysis have popularized mesenchymal stem cell (MSC) therapy via transplantation. However, the risks of tumorigenesis, immune rejection, pathogen transmission, loss of differentiation, and morphological changes after long-term culture have prompted researchers to develop a safer and more effective therapy method. Therefore, cellfree approaches have been developed to reduce the risks associated with stem cell-based therapies. In cell-free therapy of AKI and CKD, MSC-derived extracellular vesicles, with nanometer sizes, are used, called exosomes. Exosomes have a lipid bilayer membrane with various genes, microRNAs, and proteins for kidney repair. As known, MSC-derived exosomes have improved the kidney regeneration process for various reasons, such as increased safety and reduced inflammation, immune rejection, and tumorigenesis. With the advancement of exosome isolation techniques, the possibility of using biologically active molecules for renal injury prediction and diagnosis has emerged. The use of urinary exosomes in AKI and CKD diagnosis is based on changes in the expression of specific molecule cargos of exosomes. This review article summarizes the diagnosis and therapeutic applications of exosomes in AKI and CKD.