Status quo of Extracellular Vesicle isolation and detection methods for clinical utility

Extracellular Vesicles as Biomarkers in Head and Neck Squamous Cell Carcinoma: From Diagnosis to Disease-Free Survival

“…However, EV detections and applications have not been widely adopted for clinical use since we are still pursuing a greater platform that could ensure highly sensitive and specific methods, but these require minimal sample volume for testing. Additionally, the platform should be capable of detecting different cargoes delivered by EVs (i.e., DNA, RNA, proteins), since they might also be specific biomarkers for certain diseases, and if a platform for detecting EVs could realize such a high-throughput analysis for development, then the clinical application for EVs as biomarkers would be applied in future [ 30 ].…”

“…The precipitation or commercial kit is relatively efficient at isolating EVs, but reports have mentioned that there are miRNA contaminations and a decreased EV subpopulation enrichment [ 28 , 29 ]. For the other EV isolation methods, due to the small sample size for clinical applicability or validation, the detection methods of ultrafiltration, size exclusion chromatography, and immunoaffinity capture have not been put into wide clinical use [ 28 , 30 ]. The leading method to detect EVs or related biomarkers in this field, such as DNA, RNA, and proteins conveyed by EVs, involves size-based and immunoaffinity-based detection.…”

“…The leading method to detect EVs or related biomarkers in this field, such as DNA, RNA, and proteins conveyed by EVs, involves size-based and immunoaffinity-based detection. The principle is the combination method that accomplishes the attachment of the “probe”, such as the aptamers of specific EV membrane proteins or EV marker-bound magnetic beads, for detecting EVs or their intravesicular cargoes, to condense them together by the physical or chemical filters [ 30 , 31 , 32 , 33 ].…”

Clinical application of pancreatic juice‐derived small extracellular vesicles of pancreatic ductal adenocarcinoma

“…Despite the expectations raised in prior investigations, there are still some issues to be solved in relation to PJ-derived sEV-based biomarkers and therapeutic target discovery, to progress from the investigation stage to clinical application. [55][56][57][58] First, the development of a simple, reproducible and high-throughput method for the isolation of PJ-derived sEVs is essential for widespread clinical use. Second, a reliable normalization method is needed for the analysis of sEVs, for both miRNA biomarkers and protein biomarkers, although the alignment of sample volumes, compensation using synthetic nonhuman miRNAs, cel-miR-39, or the expression of multiple miRNAs, and certain sEVs markers (e.g., CD9 and CD63) have been commonly used.…”

Recent advances of small extracellular vesicle biomarkers in breast cancer diagnosis and prognosis

“…For example, in the ISEV 2018 guideline EV subtypes are classified by physical characteristics such as EV size (small EVs < 200 nm, large EVs > 200 nm), density, and biochemical composition (e.g., CD63, CD81, Annexin A5) [ 24 ]. Large EVs (lEVs) have a density 1.10–1.15 g/mL and Cav-1, CK18, and GAPDH expression, while small EVs (sEVs) are characterised by CD9, CD63, CD81, TSG101, Alix, Flotilin-1, and heat-shock proteins (HSPs) and have a density range of 1.05–1.2 g/mL [ 25 ]. Based on this classification, this review will focus on sEVs and references that refer to exosomes will fall under this group.…”