Virginia Via Research Day Book 2026

Faculty Research Biomedical

02 PRIMING ENHANCES EXTRACELLULAR VESICLE UPTAKE IN SCHWANN AND ENDOTHELIAL CELLS

Virginia Grey Fritz, DO; Sarah I. P. Santos, PhD; Zachary Simmons, DO, Taylor M. Wynne, DO; Thais Sloop, DO; Carey W. Hung, DO; Alexandre L. R. de Oliveira, PhD; Kelly C. S. Roballo DVM, PhD Corresponding author: kroballo@vcom.edu

VCOM-Virginia, Blacksburg, Virginia University of Campinas

Context: Extracellular vesicles (EVs) are vesicles released by cells that can carry waste, proteins, genetic material, and lipids throughout the body. Historically, it was thought that EVs only carried waste products out of cells, but in recent years, researchers have discovered that these EVs play a role in cell signaling, cell fusion, immune modulation, and cell regeneration. However, the research has now been directed to explore appropriate dosage of exosomes to achieve optimal healing and repair. Objective and/or Hypothesis: Our project investigated mechanisms to utilize neuron-derived and Schwann cell-derived EVs and explored how different concentrations and conditions affect their uptake into Schwann cells or endothelial cells, respectively. Further, this study developed a protocol to introduce EVs to cells in a process named here as “priming”.

Methods: We postulated that performing a first exposure of the EVs to a target cell, which means priming EVs through co-culture with the respective recipient cell type for 24 hours, would increase the EV’s tendency for uptake and long-term cell survival. Results: We found that after 24 hours of cell priming, neuron-derived EVs had optimal uptake into Schwann cells at a concentration of 10 µL, while Schwann cell-derived EVs had the greatest uptake into endothelial cells at a concentration of 25 µL, at 7 days of co-culture. Lastly, we evaluated the perinuclear localization of EVs and found no differences between primed and non-primed EVs. These experiments, however, confirmed that EVs are not retained at the outer cell membrane but are internalized into the cytoplasm and positioned near the nucleus.

Conclusion: Overall, the findings suggest that priming EVs and the concentration of EVs affect the uptake potential of EVs into cells. Optimizing these conditions could improve the therapeutic benefit of these natural messengers and EVs may later be applied as pre-conditioned treatments to target specific cells in animal models.

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115 2026 Research Recognition Day