Perspective
Open Access
Lipoproteins as overlooked RNA carriers in saliva: implications for extracellular vesicle biomarker studies
Tiago Degani Veit1,∗Fernanda Visioli2,3José Artur Bogo Chies4
1 Department of Microbiology, Immunology and Parasitology, Institute of Health’s Basic Science, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
2 Dentistry School, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
3 Experimental Center Research, Porto Alegre Clinical Hospital, Porto Alegre, Brazil
4 Postgraduate Program in Genetics and Molecular Biology, Laboratory of Immunobiology, Department of Genetics, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
  • Volume
    Volume 6 Issue 4, 2024
  • Citation
    Veit TD, Visioli F, Chies JAB. Lipoproteins as overlooked RNA carriers in saliva: implications for extracellular vesicle biomarker studies. ExRNA 2024(4):0016, https://doi.org/10.55092/exrna20240016. 
  • DOI
    10.55092/exrna20240016
  • Copyright
    Copyright2024 by the authors. Published by ELSP.
Abstract

Extracellular vesicles (EVs) are nanoscopic structures released by all cell types, playing a crucial role in cellular communication. EVs contain various types of RNAs, and a significant number of studies in the field of biomarker research have focused on the RNA content of these vesicles, particularly microRNAs. Saliva is an easily and non-invasive obtainable body fluid that is being increasingly studied for the identification of biomarkers associated with oral and systemic disorders. Early studies investigating salivary RNA distribution reported that the majority of its microRNA content seemed to be associated with EVs. Recently, an RNAseq analysis of host and microbial salivary RNA content in different salivary fractions reported that a majority of the most abundant microRNAs (miRNAs) were detected in both EV-enriched and unenriched saliva fractions. In this letter we raise the hypothesis that this high correlation regarding the miRNA content among saliva fractions might be partially explained by the presence of alternative, overlooked sources of miRNAs in saliva such as lipoproteins. The focus of this report is to raise awareness regarding potential contaminants in EV saliva preparations and to emphasize the need of further research aimed at directly assessing the contribution of these alternative miRNA carriers.

Keywords

extracellular vesicles; saliva; lipoproteins; miRNAs; biomarker research; cancer; exosomes

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