Development and Validation of Technologies for Rapid Isolation and Characterization of Extracellular Vesicles of Central Nervous System Origin

Presenter:

Geetha Senthil, Ph.D.
Office of Genomics Research Coordination

Goal:

This concept was developed by the NIMH to contribute to the NIH Blueprint for Neuroscience Research , a framework to enhance cooperative activities among NIH Institutes, Centers and Offices that jointly support neuroscience-related research.  The primary goal for the concept presented here is to develop novel methods, technologies, and validated approaches for improved cell-type specific isolation of central nervous system (CNS) extracellular vesicles (EVs) from various human biofluids. The secondary goal is the development of technology for the characterization of the composition of CNS specific EVs, including the full range of EV cargo molecules such as RNA, proteins, lipids, and metabolites.

Rationale:

EVs encompass a diverse array of cell-derived, nano-scale (100-1000 nm), membrane bound vesicles. They are ubiquitous in many biofluids and act as important mediators of extracellular signaling through their capacity to transfer proteins, lipids, and nucleic acids between cells. EVs are produced by all major CNS cell types and appear to play a role in normal physiological functions and in pathological processes. In neurodegenerative disorders and brain cancer, EVs directly influence the disease state by spreading misfolded or cancer proteins to healthy cells. The role of EVs in mental health disorders has been receiving increased attention. CNS-EVs cross the blood-brain barrier and can be found in peripheral circulation and other easily accessible biofluids (e.g. saliva, urine). The presence of CNS-EVs in such biofluids offers an opportunity to access information about brain health and function noninvasively, in living individuals. The key barrier to utilizing CNS-EVs from peripherally accessible biofluids is the limited availability of technologies and protocols that yield specific detection, isolation and characterization of CNS-EVs by cellular origin. This initiative seeks to enhance current strategies and develop new methodologies to specifically detect, isolate, and characterize – in a robust and reproducible manner – the EVs derived from different CNS cell types and as found in biofluids. Methods developed under this initiative could potentially lead to new strategies for diagnosis, prognosis, and intervention in CNS disorders, including mental health disorders.

Areas of interest under this FOA include, but are not limited to:

• Development of high-throughput isolation, specific detection, and quantification approaches and technologies for CNS-EVs.
• Development of novel or improved methods for enrichment and/or purification of CNS-EVs.
• Identification of specific markers to distinguish different CNS-EVs based on the cell type from which they were derived in biofluids, such as serum and plasma. For example, all CNS-EVs may contain common and unique surface or cargo markers where relative proportions of different elements, such as RNAs or proteins, may distinguish EVs derived from different cell types.
• Development of protocols optimized for CNS-EV isolation from different biofluid sources (e.g. saliva, plasma or urine).
• Development of methods, techniques, and/or in silico approaches to characterize the composition of CNS-EVs. These techniques may include deep characterization of EV cargo, such as RNA, protein, lipid, and/or metabolites.