In a recent publication, researchers of IMoPA’s lab together with the support of NGS Core Facility of UMS2008 IBSLor describe a thoughtful and extensive characterization of human extracellular RNAs (exRNAs) in human plasma. These species are secreted by almost any type of cell and now known to play multiple physiological roles. In human, exRNA population is found in nearly any physiological liquid and attracts growing interest as potential source for biomarker discovery.

In this work, Next-Generation sequencing was used to characterize exRNA species from blood of healthy human donors, in order to achieve the most comprehensive view of the species, sizes and origin of exRNA present in plasma fractions. Unbiased analysis of exRNA composition was performed with pre-fractionation of plasma exRNA followed by library preparation, sequencing and bioinformatics analysis.

Unexpectedly, the data show, that, in addition to “mature” RNAs species, human plasma contains a substantial proportion of degraded RNA fragments. These degraded RNAs represent the major fraction in population and mostly correspond to rRNA, in contrast to mature products which mostly contain miRNAs and hY4 RNA fragments.

Highly purified EV preparations contain a substantial proportion of exRNA of non-human origin, coming from human skin and gut microbiota, including viral microbiota. These exogenous exRNA represent up to 75-80% of total RNA reads in highly purified extracellular vesicles, opening the way for biomedical exploitation of these non-human biomarkers.

Publication : Galvanin A, Dostert G, Ayadi L, Marchand V, Velot É, Motorin Y. Diversity and  heterogeneity of extracellular RNA in human plasma. Biochimie. 2019 May 17.

DOI : 10.1016/j.biochi.2019.05.011

PMID :  31108123

HAL : HAL-02140106