Exosomes from human saliva as a source of microRNA biomarkers

Objective: The aim of this study was to examine the presence of microRNAs (miRNAs) within exosomes isolated from human saliva and to optimize and test methods for successful downstream applications. Design: Exosomes isolated from fresh and frozen glandular and whole human saliva were used as a source of miRNAs. The presence of miRNAs was validated with TaqMan quantitative PCR and miRNA microarrays. Results: We successfully isolated exosomes from human saliva from healthy controls and a patient with Sjogren's syndrome. microRNAs extracted from the exosomal fraction were sufficient for quantitative PCR and microarray profiling. Conclusions: The isolation of miRNAs from easily and non-invasively obtained salivary exosomes with subsequent characterization of the miRNA expression patterns is promising for the development of future biomarkers of the diagnosis and prognosis of various salivary gland pathologies.