Recent advance on extracellular vesicle labeling: From strategy to probe

Abstract

Extracellular vesicles (EVs) are rapidly advancing in the field of biomedicine, and play an essential role in many physiological processes. However, current understandings on EVs' behavior and distribution in vivo, as well as their sensitive and specific detection in vitro are limited. To comprehend the mechanism of action and intracellular fate, and possible applications in diagnosis and treatment of EVs, suitable labeling them is crucial. Up to now, diverse label probes and strategies towards EVs have been progressively developed, but are rarely summarized and discussed. Herein, in this review, we systematically summarize recent research progress on extracellular vesicle labeling, and focus on the development of label probes, strategy, and their applications in tracing and detection. According to the source of detection signal, the labeling methods of EVs are classified into magnetic labeling, radioactive labeling, optical labeling, and emerging metal labeling. The probes used in EV labeling are correspondingly categorized, meanwhile, their merits and drawbacks are discussed objectively. In final, the challenges and future possibilities of EV labeling are proposed. This review presents an overview of EV labeling from probes to strategies, and we hope that it will bring some inspirations to relevant researchers.