Review on Strategies and Technologies for Exosome Isolation and Purification.

Jiaci Chen,Xiaowen Huang,Peilong Li,Ruiming Wang,Lutao Du,Zhipeng Xu,Taiyi Zhang

doi:10.3389/fbioe.2021.811971

Abstract

Exosomes, a nano-sized subtype of extracellular vesicles secreted from almost all living cells, are capable of transferring cell-specific constituents of the source cell to the recipient cell. Cumulative evidence has revealed exosomes play an irreplaceable role in prognostic, diagnostic, and even therapeutic aspects. A method that can efficiently provide intact and pure exosomes samples is the first step to both exosome-based liquid biopsies and therapeutics. Unfortunately, common exosomal separation techniques suffer from operation complexity, time consumption, large sample volumes and low purity, posing significant challenges for exosomal downstream analysis. Efficient, simple, and affordable methods to isolate exosomes are crucial to carrying out relevant researches. In the last decade, emerging technologies, especially microfluidic chips, have proposed superior strategies for exosome isolation and exhibited fascinating performances. While many excellent reviews have overviewed various methods, a compressive review including updated/improved methods for exosomal isolation is indispensable. Herein, we first overview exosomal properties, biogenesis, contents, and functions. Then, we briefly outline the conventional technologies and discuss the challenges of clinical applications of these technologies. Finally, we review emerging exosomal isolation strategies and large-scale GMP production of engineered exosomes to open up future perspectives of next-generation Exo-devices for cancer diagnosis and treatment.

Highlights

The development of medical technologies has reached an unprecedented level in the 21st century
It is worth noting that the isolated exosomes may contain other impurities with membrane because the methods are mainly based on lipid bilayer-closed structures
Wu and others fabricated an acoustic-based microfluidic device consisting of two acoustofluidic modules for removing larger blood components and separating exosomes, respectively (Wu et al, 2017)

Summary

Introduction

The development of medical technologies has reached an unprecedented level in the 21st century. The specific steps are to remove large impurities by low-speed centrifugation, and the sample is added to the top of the separation medium for ultracentrifugation (Figure 4B). Different from the powerful force of ultracentrifugation, exosome separation can be accomplished only by gravity or low-speed centrifugation in this method, maintaining the biological function of exosomes (Batrakova and Kim, 2015).

Results

Conclusion