Specificity Evaluation Service for Exosome Product

Fig. 1 Schematic illustration of the molecular
composition of exosomes. (Kimiz-Gebologlu, 2022)

The composition of exosomes (Exos) is related to the source and type of secreting cells. Exos have been widely considered as a potential drug delivery vehicle and drug delivery system. Large-scale production of qualified Exo products can provide reliable raw materials for drug development, help researchers develop and optimize the application of Exos as drug delivery systems, and accelerate the process of drug development and transformation. In the qualification process of Exo products, the specificity evaluation of Exo products is a very important link. In order to ensure the functional specificity of Exo products and meet customer needs, Creative Biolabs provides high-quality specificity evaluation service for Exo products.

Three Types of Exosome-specific Markers

Specific markers for Exo themselves

The distinctive identifiers of Exos pertain to proteins that exhibit significant enrichment both on the surface and within the confines of Exos. Examples of these markers include CD9, CD81, and TSG101, which are utilized widely for the purpose of Exo identification. This is primarily due to their profound involvement in the process of Exo formation and release, and their marked concentration within the Exo.

Inherited specific markers in Exo

Exos are formed through the endoplasmic reticulum and multivesicular systems within cells, and these intracellular structures fuse with the Exo membrane during Exo formation, resulting in the enrichment of some donor cell-specific proteins on the Exos. For example, the specificity of Exos secreted by neuronal cells mainly lies in containing L1 cell adhesion molecular. In addition, since Exos are the carrier of material exchange between cells, donor cells will release Exos containing specific regulatory molecules or ligands, allowing Exos to regulate other recipient cells on their own behalf. For example, Exos derived from dendritic cells have CD40 ligand on their surface, which can bind to CD40 receptors on the surface of target cells.

Loaded specific markers in Exo

Since Exos can be engineered before being secreted and after being secreted, engineered Exos are endowed with various specific targeting functions, including modified molecules targeting specific tissues or cells and targeting and therapeutic molecules targeting specific genes or pathways within recipient cells. For example, Brain-targeting peptide rabies virus glycoprotein is loaded onto Exos by endogenous modification as usual.

For large-scale production of Exo products, the quality and application effect of Exo products can be improved by ensuring the correctness and effectiveness of the above three types of specific markers.

Comprehensive Exosome Specificity Evaluation Service at Creative Biolabs

Creative Biolabs has the ability to provide the most comprehensive Exo specificity evaluation service, specifically covering the following technical services.

Published Results of Stability Evaluation of Exosome Product

Technical service	Evaluation advantage
Nano flow cytometry	Rapid detection of specific markers on the surface of Exos based on a small sample volume. This method has high sensitivity and can simultaneously detect multiple molecules on the surface of Exos.
Western blot	By being recognized and bound by specific antibodies, the amount of target Exo-specific marker protein is presented as band intensity. The relative content of the protein can be estimated by equal total protein loading and band grayscale analysis.
Enzyme-linked immunosorbent assay	Based on the recognition and binding of antibodies or antigens, the amount of target Exo-specific marker protein is presented in color intensity. This method has the advantage of high-throughput detection and is suitable for large-scale samples.
Mass spectrometry	All the molecules contained in Exos serve as fingerprints of Exos, which can be analyzed by mass spectrometry and presented as molecular profile. You can also evaluate the content of interested molecules in Exos through targeted omics analysis.
RNA analysis	The target RNA can be quantitatively analyzed by gene amplification.
Efficacy verification	Whether the specific markers in Exos can exert function can be evaluated by conducting in vivo and in vitro functional experiments of Exo products.

If you plan or are in the process of large-scale production of Exos and need to evaluate the specificity of the expected or obtained Exo products, please contact us.

Reference

Kimiz-Gebologlu, I.; Oncel, SS. Exosomes: large-scale production, isolation, drug loading efficiency, and biodistribution and uptake. Journal of Controlled Release. 2022. 347:533-543.

Plant Exosome Isolation