Isolation and application of milk exosomes
Introduction
Extracellular vesicles (EVs) are small membrane-bound particles released by a variety of cells, including milk cells. Milk-derived EVs are known as milk EVs (mEVs) or milk microvesicles. Studies have shown that mEVs contain many biologically active molecules, including proteins, lipids, and nucleic acids, which have implications for both human and animal health.
Several studies have highlighted the potential therapeutic benefits of mEVs, including their use as drug delivery vehicles, immunomodulators, and therapeutic agents in disease treatment. However, before these potential applications can be fully realized, important questions need to be addressed, including the most effective methods for mEV isolation and characterization.
Milk EV isolation methods
Several methods are currently used for the isolation and characterization of mEVs, and these have been extensively reviewed elsewhere (1, 2). Here, we briefly summarize some of the most commonly used methods.
Method 1: Ultracentrifugation (3)
Ultracentrifugation is currently the most widely used method for mEV isolation. This method involves centrifuging milk samples at high speeds to separate the mEVs from other milk components. However, this method may not be suitable for the isolation of mEVs from small volumes of milk or for sensitive downstream applications.
Method 2: Size exclusion chromatography (SEC) (4)
SEC is a chromatography-based technique that separates mEVs based on their size. This method has been shown to be effective for the isolation of highly pure mEVs, but it is time-consuming and may not be suitable for the isolation of mEVs from large volumes of milk.
Method 3: Immunoaffinity capture (5)
Immunoaffinity capture involves using specific antibodies to capture mEVs from milk samples. This method is highly specific and allows for the isolation of mEVs from small volumes of milk. However, the use of antibodies can affect the downstream applications of the isolated mEVs.
mEV characterization methods
Once mEVs have been isolated, various methods can be used to characterize their size, shape, and composition. Here, we summarize some of the most commonly used methods.
Method 1: Transmission electron microscopy (TEM) (6)
TEM is a microscopy-based technique that allows for the visualization of mEVs and their internal structure. This method can provide information on mEV size, morphology, and the presence of other components such as proteins and lipids.
Method 2: Dynamic light scattering (DLS) (7)
DLS is a light-scattering-based technique that measures the size distribution of mEVs in solution. This method is relatively quick and easy to perform, but it may not accurately reflect the size distribution of mEVs in complex biological samples.
Method 3: Western blotting (8)
Western blotting is a protein detection technique that can be used to identify specific proteins in mEVs. This method allows for the detection of specific proteins in mEVs and can provide information on mEV composition.
Clinical applications of mEVs
mEVs have a wide range of potential clinical applications, including drug delivery, cancer diagnosis and treatment, and immune modulation. Here, we briefly summarize some of the most promising clinical applications.
Application 1: Drug delivery (9)
mEVs have shown promise as drug delivery vehicles due to their ability to encapsulate hydrophobic and hydrophilic molecules and their ability to target specific cells. This application has the potential to revolutionize drug delivery by providing a new way to deliver therapeutics to specific tissues or organs.
Application 2: Cancer diagnosis and treatment (10)
mEVs have been shown to contain tumor-specific markers, making them a potential diagnostic tool for cancer. Additionally, mEVs have been shown to play a role in tumor growth and metastasis, making them a potential target for cancer treatment.
Application 3: Immune modulation (11)
mEVs have been shown to play a role in immune regulation, making them a potential therapeutic agent for the treatment of autoimmune diseases, allergies, and other immune-related disorders.
Conclusion
mEVs have the potential to revolutionize the field of medicine by providing new diagnostic and therapeutic tools for a wide range of diseases. However, before these potential applications can be fully realized, important questions need to be addressed, including the most effective methods for mEV isolation and characterization.
References:
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