Figure 1.

Diversity of exRNA carriers in biofluids

exRNA are associated with a plethora of carriers ranging from a few nanometers to several microns. Although EVs are the most studied exRNA carriers, RNPs, exomeres, supermeres, lipoproteins, and extracellular organelles are associated with a high proportion of exRNA in biofluids. Their relative abundance may explain the specific exRNA biotype composition observed in distinct biofluids. During viral infection, RNA viruses also constitute a significant exRNA carrier in specific biofluids, a property exploited for diagnostics. Here, all known exRNA carriers are represented at scale thereby illustrating their high size heterogeneity, and the challenge to fractionate them in parallel. Acronyms: RNP: ribonucleoprotein; HDL. High-density lipoprotein; LDL: Low-density lipoprotein; VLDL: Very-Low Density Lipoprotein; EVs: extracellular vesicles; SARS-Cov-2: severe acute respiratory syndrome coronavirus two; HIV-1: Human immunodeficiency virus 1.