Exosomes are nanosized membrane vesicles that are secreted from the cell and present in various eukaryotic fluids, such as blood and urine. And they are spherical, bilayered proteolipids and show a diverse mixture of proteins, DNAs, RNAs, and lipids. It is reported that exosomal proteins have an essential role in the pathological process of diseases. Therefore it is necessary to analyze and identify exosomal proteins. Advanced progress in mass spectrometry (MS)-based proteomic analyses of mammalian exosomes derived from different cell types and body fluids have led to the identification of thousand vesicular proteins. With the help of Creative Biolabs, an expert in exosome technical services, essential clues can be provided for customers to decipher molecular mechanisms involved in vesicle cargo sorting, biogenesis and protein functions of exosomes.
Initial proteomic analysis indicated that exosomes harbor a specific subset of cellular proteins, some of which rely on the cell that secretes them, while others are observed in most exosomes regardless of cell types. The latter contains proteins from endosomes, the cytosol, and the plasma membrane (PM), whereas proteins from the nucleus, mitochondria, Golgi complexes, and endoplasmic reticulum are mostly absent. These findings highlight the specificity of vesicle formation and demonstrate that they represent a specific subcellular compartment but not a random array of cell components.
Fig.1 Protein interaction networks of human extracellular vesicles. (Choi, 2013)
The protein content in exosomes has been extensively studied since the initial description. Technologies allowing antibody-based detection (such as western blotting, immuno-EM) of particular proteins were first used and then with the development of proteomic techniques soon permitted large-scale identification of unknown proteins. Nowadays, high-throughput proteomic analyses of exosomes are able to reveal the presence of extracellular matrix and cell surface proteins including collagens, galectin, and integrins.
Characterization of exosomal cargo is of great interest because the cargo can offer clues to exosome biogenesis, formation, targeting, and cell effects and is likely to be a source of biomarkers for disease diagnosis, prognosis and response to treatment. In Creative Biolabs, we have improved proteomics technologies to determine both qualitative and quantitative features of exosomal proteins. Meanwhile, we focus on exosome proteomics studies all along and provide detailed protocols for global customers with quantitative analysis of targeted exosomal proteins.
In addition to exosome proteomics services, Creative Biolabs provides well-established platforms that allow to isolate, extract, and analyze exosome from almost any tissue or biofluid. If you don’t find related products or services needed, you can reach us by email taking special requirements.