Exosome Labeling and Tracking Services
As a medium of intercellular communication between cells, exosomes are uptaken through different routes and mechanisms, including fusion with the plasma membrane as well as receptor-mediated endocytosis, phagocytosis, lipid raft-dependent endocytosis and other endocytic pathways. Since the use of exosomes for therapeutic mRNA delivery has gained more and more attention. The reliable and effective techniques for monitoring exosomes in cell endocytosis and the in vivo biodistribution are highly desirable. Particularly, it is an essential step to analyze the biodistribution of exosomes, which contributes to the determination of therapeutic dose as well as prediction of the potential side effects of exosomes. Exosome labeling are a novel strategy for visualizing and tracking exosomes, which promotes the development of exosome-based diagnosis and treatment. With professional scientists and advanced technologies, Creative Biogene is committed to providing customized exosome labeling and tracking services to customers from all over the world.
Monitoring methods for exosomes
Monitoring exosomes in vivo can provide important information about their mechanism of targeting action, biodistribution, migration abilities, physiological functions, and toxicity. To date, there are different methods developed for exosome tracking, involving bioimaging modalities and exosome labeling methods.
In vivo imaging methods for exosome tracking
The bioimaging modalities provide real-time in vivo imaging of the administered exosomes. To achieve the desired imaging and therapeutic goals, the selection of appropriate imaging technology is important. Currently, the available imaging technologies, such as bioluminescence imaging (BLI), fluorescence, magnetic resonance imaging (MRI), and nuclear imaging modalities, have different capabilities regarding biocompatibility, spatial and temporal resolution, penetration depth, and so on. Among them, BLI has the highest sensitivity and high signal-to-noise ratio. However, BLI with luciferase and fluorescence imaging with near-infrared (NIR) fluorescent dyes are limited by spatial-temporal resolution. Nuclear imaging modalities are a feature of the highest penetration, low spatial resolution, and high cost. While, MRI is known to have high penetration and spatial-temporal resolution, but low sensitivity and high cost.
Various strategies have been developed in order to elucidate exosome trafficking and selective targeting in vivo. (Betzer, O.,et al. 2020)
Labeling methods for exosomes
For in vivo imaging, exosomes labeled with probes using proper methods are essential. Various methods include membrane integration, internalization, covalent binding, and genetic modification, have been used to label exosomes.
Table 1. Comparison of labeling methods.
| Labeling Methods | Pros | Cons |
| Covalent biding | Tight binding of probes to proteins | Cannot distinguish between exosomes vs. non-exosome proteins May change membrane protein functions which affect the interaction of exosomes with target cells |
| Genetic modification | Can avoid surface modification | Genetic change of cells may change the property of cells and/or exosomes Uneven loading into exosomes |
| Membrane integration (lipophilic fluorescent dyes) |
Simple and easy | May cause clumping of exosomes Cannot distinguish between lipid proteins and micelle May cause background signals from dissociated probes May cause pseudo signals even after clearance of exosomes May affect the interaction of exosomes with target cells |
| Encapsulation by electroporation | May avoid surface modification | May cause aggregation or fusion of exosomes |
| Encapsulation by lipophilic agents | Simple and easy | May cause background signals from released probes |
| Transporter-dependent encapsulation | Simple and easy | Depends on the transporter (e.g., GLUT1) Un-even encapsulation May cause background signals from released probes |
| Metabolic labeling | Covalent binding of probes by click chemistry | May change the property of cells and/or exosomes May change membrane protein functions which affect the interaction of exosomes with target cells |
Yi, Y. W., et al. 2020 (International journal of molecular sciences)
Service offering in Creative Biogene
With efficient exosome labeling methods and professional detection equipment, we are offering customized exosome labeling and tracking services according to specific projects of our global customers. For exosome labeling, we offer two different strategies, including direct labeling and indirect labeling approaches. Based on the endogenous labeling technique and the exogenous labeling technique, our specific services include,
- Exosome tracking based on exosomal lipid labeling
- Exosome tracking based on exosomal protein labeling
- Exosome tracking based on exosomal RNA labeling
If you are interested in our services, please feel free to contact us. We will reply to your message shortly.
References
- Yi, Y. W., et al. (2020). "Advances in analysis of biodistribution of exosomes by molecular imaging." International journal of molecular sciences, 21(2), 665.
- Betzer, O., et al. (2020). "Advances in imaging strategies for in vivo tracking of exosomes." Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology, 12(2), e1594.