GSE122621
Comparability of the small RNA secretome across human biofluids concomitantly collected from healthy adults
Small extracellular vesicles (sEV) are nano-sized (40-150 nm), membrane-encapsulated vesicles that are released by malignant or pathologic and non-pathologic cells into the extracellular space and function as intercellular signaling vectors through the horizontal transfer of biologic molecules, including microRNA (miRNA) and other small non-coding RNA (ncRNA), that can alter the phenotype of recipient cells. sEV are present in essentially all extracellular biofluids, including serum, urine and saliva, and offer a new avenue for discovery and development of novel biomarkers of various disease states and exposures. The objective of this study was to determine the similarities and differences between sEV ncRNA derived from saliva, serum and urine, as well as cell-free ncRNA from serum. Saliva, urine and serum were concomitantly collected from 4 healthy donors, and sEV were isolated from each respective biofluid, along with cfRNA from serum. sEVs were isolated from the respective biofluids via differential ultracentrifugation. Small RNA-sequencing was performed on each sample, and cluster analysis was performed based on ncRNA profiles. While some similarities existed in terms of sEV ncRNA cargo across biofluids, there are also notable differences in ncRNA class and ncRNA secretion, with each sEVs in each biofluid bearing a unique ncRNA profile. We conclude that sEV ncRNA cargo varies according to biofluid, so thus should be carefully selected and interpreted when designing translational or epidemiological studies. Overall design: Saliva, urine and serum were concomitantly collected from 4 healthy donors, and sEV were isolated from each respective biofluid, along with cfRNA from serum. sEVs were isolated from the respective biofluids via differential ultracentrifugation. Small RNA-sequencing was performed on each sample, and cluster analysis was performed based on ncRNA profiles.