Combination of precipitation and size exclusion chromatography as an effective method for exosome like extracellular vesicle isolation from pericardial fluids

Extracellular vesicle biomarkers in ocular fluids associated with ophthalmic diseases

Extracellular vesicles (EVs) are released as highly stable lipid bilayer particles carrying proteins, lipids, glycans and miRNAs. The contents of EVs vary based on the cellular origin, biogenesis route and the functional state of the cell suggesting certain diseased conditions. A growing body of evidence show that EVs carry important molecules implicated in the development and progression of ophthalmic diseases. EVs associated with ophthalmic diseases are mainly carried by one of the three ocular biofluids which include tears, aqueous humor and vitreous humor. This review summarizes the list of EV derived biomarkers identified thus far in ocular fluids for ophthalmic disease diagnosis. Further, the methods used for sample collection, sample volume and the sample numbers used in these studies have been highlighted. Emphasis has been given to describe the EV isolation and the characterization methods used, EV size profiled and the EV concentrations analyzed by these studies, thus providing a roadmap for future EV biomarker studies in ocular fluids.

Encapsulation and assessment of therapeutic cargo in engineered exosomes: a systematic review

Exosomes are nanoscale extracellular vesicles secreted by cells and enclosed by a lipid bilayer membrane containing various biologically active cargoes such as proteins, lipids, and nucleic acids. Engineered exosomes generated through genetic modification of parent cells show promise as drug delivery vehicles, and they have been demonstrated to have great therapeutic potential for treating cancer, cardiovascular, neurological, and immune diseases, but systematic knowledge is lacking regarding optimization of drug loading and assessment of delivery efficacy. This review summarizes current approaches for engineering exosomes and evaluating their drug delivery effects, and current techniques for assessing exosome drug loading and release kinetics, cell targeting, biodistribution, pharmacokinetics, and therapeutic outcomes are critically examined. Additionally, this review synthesizes the latest applications of exosome engineering and drug delivery in clinical translation. The knowledge compiled in this review provides a framework for the rational design and rigorous assessment of exosomes as therapeutics. Continued advancement of robust characterization methods and reporting standards will accelerate the development of exosome engineering technologies and pave the way for clinical studies.

A comparison of size exclusion chromatography-based tandem strategies for plasma exosome enrichment and proteomic analysis

Proteomic analysis of exosomes from human plasma faces a tremendous challenge mainly due to the low abundance of the exosome itself and the complexity of the plasma matrix. Therefore, enrichment of exosomes from human plasma is an essential and indispensable step for large scale and in depth proteomic analysis. Size exclusion chromatography (SEC) is one of the most extensively used methods for exosome isolation from human plasma and many SEC-based tandem methods were established in order to increase the purity of the enriched exosomes and thus the accuracy of the proteomic analysis. To compare the advantages and disadvantages of the different isolation methods and subsequently to promote the establishment of a standardized method for plasma proteomic research, the capacities of the direct SEC method, the combination of SEC with ultracentrifugation (SEC-UC), ultrafiltration (SEC-UF), and titanium dioxide microspheres (SEC-TiO2) were systematically evaluated for exosome isolation from human plasma and thus proteomic analysis. The results demonstrated that the SEC-based tandem methods were superior to the direct SEC method in the purity of exosomes isolated from human plasma. Additionally, the SEC-UC method possessed the highest number of the total identified proteins and the overlapped proteins with the top 100 exosome markers in comparison with the other methods. The SEC-TiO2 method displayed the biggest capacity for plasma protein deleting. We expect that the research will have more beneficial values in the field of exosome research.