Exosomes are spherical to cup-shaped bilayered membrane enclosed nanosize vesicles (30-100 nm) which have the ability to shuttle active cargoes between cells. Johnstone et al. 1987 pioneered in documenting the generation of exosomes in differentiating reticulocytes as a result of the fusion of multi-vesicular endosomes/MVBs with the plasma membrane. However, later studies established that exosomes are actively secreted by almost all types of cells through the process of exocytosis and that exosomes can be found in most of the body fluids (blood, saliva, semen and urine). Structurally, exosomes contain various types of biomolecules (lipids, proteins, DNA, RNA etc.) from the parent cells, and the bacterial/viral proteins or nuclear acids in infected cells. Exosomes act as signalosomes and facilitate intercellular communication through delivering bioactive molecules (Tran et al. 2015)
Owing to their biomedical significance, exosomes have been of great interest to researchers in the last few yars. Exosomes are now known to implicate in cellular signaling, metabolic pathways, development/regeneration, cell adhesion/motility, immunosuppression or immunoactivation, inflammation, infectious pathogenesis, cancer progression/metastasis, stemness /reprogramming, hepatic and cardiovascular diseases, and development and homeostasis of nervous system as well as various neurodiseases (Parkinson's, Alzheimer's and ALS).
Isolation, quantification, characterization and analysis of exosomes (or their contents) are essential for delineating their role in physiology, pathology or related therapeutics. Differential centrifugation is one of the most commonly used techniques for exosome isolation which involves serial centrifugation (200 to 100,000×g) of cell contents or supernatants, finally sedimenting the exosomes at 100,000×g (Ha et al. 2106). Besides being time consuming and requiring technical expertise as well as sophisticated instrument, the major drawback of this technique is the contamination of exosomal fraction with aggregates of cellular proteins and debris/particulates.
Antibody based immunocapture tools are emerging as an easy, quick and highly specific options in exosome research. The isolation of exosomes in these methods is dependent on specific antibodies against exosome-associated antigens such as Alix, CD9, CD24, CD63, CD81, CD82 and TSG101. For expediting the research on exosomes, Novus Biologicals has enabled scientists with the tools they need for the isolation, quantification and analysis of normal or disease related exosomes. Some of our offerings on these tools are:
Also see: Exosomes Research >>>
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