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Microbial Extracellular Vesicles (EVs)

What are EVs ?
Nanometer-sized extracellular lipid bi-layered vesicles containing genetic material, proteins, & metabolites that are released from cells and carried systemically throughout our bodies
What is the function of EVs?
Key Messenger of Cell-to-Cell Communication:
EVs deliver cellular components to cells throughout the body with immune modulating properties that influence health and disease
When do cells release EVs?
All cells, both human and bacterial, universally release EVs throughout their proliferation including exosomes and ectosomes, as well as upon cell death (apoptotic bodies)

History of Microbial EVs

Although bacterial vesicles have been well characterized in gram-negative bacteria (also called outer membrane vesicles (OMV)) as early as 1966 in Escherichia coli, it wasn’t until 1989 that DNA and RNA were discovered to be contained in “microbial blebs” released from another gram-negative bacteria Neisseria gonorrhoeae. For a long time, extracellular vesicles (EVs) were given little thought and dismissed as the cellular equivalent of a waste disposal system.

However, as awareness of EVs’ functional capacity as cell-to-cell communication tools came to light, further scrutiny was given to the potential of gram-positive bacteria despite their thick membrane walls. It was then in 2009 that our group found via proteomic analysis that gram-positive bacteria such as Staphylococcus aureus, also releases EVs. This discovery in coincidence with the microbiome revolution at the time led to the establishment of MD Healthcare with the goal of developing precision healthcare solutions based on microbiome and EV convergence biotechnology.


Gram-negative bacteria release EVs
Electron microscopy enabled discovery that E. coli secretes outer membrane vesicles (OMVs)

Work E, et al. Am N Y Acad Sci 1966


Bacterial EVs contain DNA & RNA
Nucleic acid including DNA and RNA reported in “microbial blebs” released by N. gonorrhoeae

Dorward DW, et al. J Bacteriol 1989


Gram-positive bacteria release EVs
Our research team discovers that S. aureus releases EVs, first gram-positive bacteria determined to release EVs

Lee EY, et al. Proteomics 2009


Establishment of MD Healthcare Inc.
Fouded micobiome-based healthcare 4.0 company specializing in microbial EVs-based biotechnology
MD Healthcare

Importance of Microbial EVs in Precision Medicine

Through our continued research of microbial EVs, we have confirmed the importance of microbial EVs in precision medicine targeting chronic, inflammatory disease. Some key highlights of our currently published reports include the role of a variety of bacterial EVs as potential etiological agents in insulin resistance & diabetes, pulmonary disease such as asthma & chronic obstructive pulmonary disease (COPD), as well as atopic dermatitis. Microbial EVs primary influence our health by increasing our inflammatory immune responses that increase our risk to develop a variety of chronic illnesses. In total, these finding lead us to believe that the unique composition of microbial EVs within our bodies play a tremendous role in health and disease.