Perspectives of microscopy methods for morphology characterisation of extracellular vesicles from human biofluids

Malenica, Mladenka (author), Wechtersbach, Karmen (author), Kojc, Nika (author)

Extracellular vesicles (EVs) are nanometric membranous structures secreted from almost every cell and present in biofluids. Because EV composition reflects the state of its parental tissue, EVs possess an enormous diagnostic/prognostic potential to reveal pathophysiological conditions. However, a prerequisite for such usage of EVs is their detailed characterisation, including visualisation which is mainly achieved by atomic force microscopy (AFM) and electron microscopy (EM). Here we summarise the EV preparation protocols for AFM and EM bringing out the main challenges in the imaging of EVs, both in their natural environment as biofluid constituents and in a saline solution after EV isolation. In addition, we discuss approaches for EV imaging and identify the potential benefits and disadvantages when different AFM and EM methods are applied, including numerous factors that influence the morphological characterisation, standardisation, or formation of artefacts. We also demonstrate the effects of some of these factors by using cerebrospinal fluid as an example of human biofluid with a simpler composition. Here presented comparison of approaches to EV imaging should help to estimate the current state in morphology research of EVs from human biofluids and to identify the most efficient pathways towards the standardisation of sample preparation and microscopy modes.

• Language: English
• Keywords: extracellular vesicles, human biofluids, nanotechnology, atomic force microscopy, electron microscopy, morphology
• Work type: Article
• Typology: 1.02 - Review Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 29 str.
• Numbering: Vol. 9, iss. 6, art. 603
• PID: 20.500.12556/RUL-135645
• UDC: 54
• ISSN on article: 2227-9059
• DOI: 10.3390/biomedicines9060603
• COBISS.SI-ID: 64802819
• Publication date in RUL: 23.03.2022

Record is a part of a journal

• Title: Biomedicines
• Shortened title: Biomedicines
• Publisher: MDPI
• ISSN: 2227-9059
• COBISS.SI-ID: 523006745

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.06.2021