Brain Derived Exosomes; a non-invasive look inside the brain

Exosomes are small extracellular vesicles about the size of influenza and corona viruses and have been making news for several years due to their diagnostic and therapeutic potential.  Cells throughout the body produce exosomes and release them into the extracellular spaces. Originally thought to be a process to dispose of cellular waste, it is now known that exosomes represent a cell-to-cell communication network, carrying proteins, RNAs, and other biomolecules from the cell of origin to other cells locally and through the bloodstream to distant organs.  Due to their presence in blood and other biological fluids, the detection and isolation of exosomes has contributed to significant advancement in liquid biopsies for diagnosis and research.

A characteristic of exosomes is that they are able to cross the Blood Brain Barrier allowing for selective capture of brain-derived exosomes (BDE) from the blood. This creates the opportunity to evaluate changes in brain cells through a minimally invasive blood test.  Because exosomes are derived from a mother cell, the exosome membrane bears the molecular characteristics of that cell. As a result, BDE can be captured from blood samples using antibodies directed to specific surface molecules expressed on the parent brain cell.  Studies have shown that in progressive diseases such as Alzheimer’s and Parkinson’s, changes in blood BDE biomarkers can be detected years prior to and after the onset of observable clinical symptoms. Thus, even subclinical changes that occur in the brain cells of origin may be detected by BDE biomarkers before overt disease or progression in some cases.  In other clinical settings such as stroke and traumatic brain injury (TBI), analysis of BDE changes and associated biomarkers can provide a minimally invasive means to track the progression or regression of resulting damage or trauma to the brain. Moreover, with the advances in molecular biomarkers and sensitive selective BDE assays, this form of liquid biopsy has enormous potential in basic and clinical research for multiple types of brain trauma, dysfunction and disease.  As exosomes are highly stable while in circulation and under laboratory conditions, they can be used to identify changes from a normal state, monitor disease progression, and measure a therapeutic response.  Our company, NanoSomiX, has worked with both academic institutions and pharmaceutical companies on projects that range from new biomarker identification and clinical research to potential companion diagnostics. 

As our research uses sample sets from a variety of neurological disorders and controls, we have made significant research and clinical observations in working with BDEs.  For example, we now know that neuron-derived exosomes (NDE) in the blood under normal conditions vary greatly from person to person, but the number is generally stable within an individual over extended times. It is also clear that NDE levels can change dramatically in response to external traumatic clinical events.  This suggests that disease progression or therapeutic responses may be monitored in an individual by assessment of types of blood BDE.  NanoSomiX is also now working on BDE subtypes including neurotransmitter-specific dopaminergic and serotonergic NDEs, astrocyte-derived exosomes (ADE) and oligodendrocyte-derived exosomes (ODE). How changes in these various types of circulating neurologic exosomes fluctuate with disease and alterations in the brain is a major focus of our research and collaborations.

If you are interested to see how analysis of BDE may help with your research or clinical project, please contact vclements@nanosomix.com.  Our flexibility allows us to work with your team on a fee-for-service basis or collaboratively on a longer-term project.  Together, let’s see how BDEs can enhance your work.