Bacterial extracellular vesicles in biofluids as potential diagnostic biomarkers

ABSTRACT

Introduction

Extracellular vesicles (EVs) are spherical membrane-derived lipid bilayers released by cells. The human microbiota consists of trillions of microorganisms, with bacteria being the largest group secreting microbial EVs. The discovery of bacterial EVs (BEVs) has garnered interest among researchers as potential diagnostic markers, given that the microbiota is known to be associated with various diseases and EVs carry important macromolecular cargo for intercellular interaction.

Areas covered

The differential bacterial composition identified from BEVs isolated from biofluids between patients and healthy controls may be valuable for detecting diseases. Therefore, BEVs may serve as novel diagnostic markers. Literature search on PubMed and Google Scholar databases was conducted. In this special report, we outline the commonly used approach for investigating BEVs in biofluids, the 16S ribosomal RNA gene sequencing of V3-V4 hypervariable regions, and the recent studies exploring the potential of BEVs as biomarkers for various diseases.

Expert opinion

The emerging field of BEVs offers new possibilities for the diagnosis of various types of diseases, although there remain issues that need to be resolved in this research area to implement BEVs in clinical applications. Hence, it is important for future studies to take these challenges into consideration when investigating the diagnostic value of BEVs

KEYWORDS:

• Bacterial extracellular vesicles
• biofluids
• biomarkers
• diagnosis
• gene sequencing
• microbiota

Article highlights

• Cells release spherical membrane-derived lipid bilayers known as extracellular vesicles (EVs), which are found to carry essential macromolecular cargo for intercellular interaction.

• The human microbiota is known to play an important role in many diseases, and it consists of trillions of microorganisms whereby bacteria are the largest group that secrete microbial EVs.

• Differential bacterial composition determined from bacterial EVs (BEVs) in biofluids between healthy controls and patients may be valuable for identifying diseases.

• BEVs hold great potential in the field of disease diagnosis and could serve as novel biomarkers for various types of pathological conditions.

• Currently, there remain issues that need to be resolved in the research area of BEVs. Addressing these challenges in future studies will help to advance the clinical application of BEVs in disease diagnosis.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewers disclosure

Peer reviewers on this manuscript have no relevant financial relationships or otherwise to disclose.

Additional information

Funding

This work was supported by the Monash University Malaysia School of Pharmacy’s Pilot Research Grant 2022 (SOP/SRG-Pilot/02/2022) & School of Science’s Strategic Funding Scheme 2022 (STG-000125).