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Abstract: SA-PO167

Assessment of Extracellular Vesicles Isolated from the Culture Medium of Ischemic Renal Proximal Tubular Epithelial Cells

Session Information

  • AKI: Mechanisms - III
    November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
    Abstract Time: 10:00 AM - 12:00 PM

Category: Acute Kidney Injury

  • 103 AKI: Mechanisms

Authors

  • Silva Neres dos Santos, Raquel, Universidade Federal do ABC, Santo Andre, SP, Brazil
  • Carneiro-Ramos, Marcela Sorelli, Universidade Federal do ABC, Santo Andre, SP, Brazil
  • Burger, Dylan, University of Ottawa, Ottawa, Ontario, Canada
Background

Extracellular vesicles (EVs) are membranous particles released by a cell into the extracellular environment. They play an emerging and important role in cell communication and have been implicated in a variety of pathological conditions including acute kidney injury and chronic kidney diseases. Our objective was to characterize the dynamics of extracellular vesicle release by proximal tubular epithelial cells exposed to hypoxia and reoxygenation (H/R).

Methods

Primary human renal proximal tubule epithelial cells (hPTECs, n=3) were exposed to 24 hours of 1% hypoxia followed by 3 hours of reoxygenation. Proximal tubule phenotype was verified by megalin immunofluorescence and EVs were isolated from the conditioned culture medium by ultracentrifugation (100.000g for 1h30min). Extracellular vesicle size and quantity were assessed by nanoparticle tracking analysis (NTA) and EV protein quantification.

Results

The immunofluorescence analysis indicated hPTECs were megalin-positive and this was not altered by H/R. NTA indicated that the H/R exposed cells released ~2-fold more EVs than normoxia (p<0.05). This was further supported by an increase in EV protein in conditioned media of H/R vs normoxia (1.08±0.17 vs 0.75±0.12 µg/µl, p<0.05). The mean particle sizes were not significantly different between H/R (153.5nm) and normoxia (145.8nm) groups.

Conclusion

Our initial data suggest that under hypoxia induces a shift in EV release from proximal tubule cells with greater EV release. These findings suggest that proximal tubule EV release may be altered in the context of ischemic kidney disease. Such changes may contribute to disease pathogenesis.

Funding

  • Government Support – Non-U.S.