Abstract: SA-PO040
Screening of Drugs for Nephrotoxicity Using a Microfluidic Proximal Tubule on-a-Chip
Session Information
- Engineering-Based Approaches to Problems in Nephrology
November 09, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bioengineering
- 300 Bioengineering
Authors
- Donoghue, Leslie, University of Alabama at Birmingham, Birmingham, Alabama, United States
- Sethu, Palaniappan, University of Alabama at Birmingham, Birmingham, Alabama, United States
Background
Off target effects of pharmaceutical drugs account for approximately 20% of all patients diagnosed with acute renal failure. To avoid such scenarios and prevent drugs that have nephrotoxic effects from advancing past pre-clinical testing to late-stage clinical trials, it may be necessary to evaluate drug induced nephrotoxicity early during the drug discovery cycle to ensure safety and minimize costs associated with drug failure in late-stage clinical trials.
Methods
We engineered a scaffold that enables co-culture of human proximal tubule epithelial cells (RPTEC) with renal microvascular endothelial cells (MVEC) on either side of a porous polycarbonate membrane which enables cell-cell and soluble factor communication and facilitate reabsorption. The surface was coated with Collagen IV for cell attachment and approximately 1x106 cells of each RPTECs and MVECs were seeded on each side of the membrane. The device was then integrated into a microfluidic flow loop assembly to match physiological and biomechanical conditions associated with tubular flow and resorption to accurately recreate the proximal tubule.
Results
We evaluated the cells integrated within a flow loop to determine the effects of fluid shear associated with tubular flow. Our results indicate that the cells can be grown to confluence and can be maintained in culture under fluid flow at physiological levels of shear (approximately 0.1 dynes/cm2). We used immunofluorescence to determine confluency using phalloidin for actin skeleton, LIVE/DEAD® for cell viability, and occuldin for the establishment of barrier function. These stains provided insight of cell-cell tight junction formation, monolayer integrity, and paracellular permeability in polarized and transporting RPTECs.
Conclusion
In this project, we were able to recreate the architecture of the proximal tubule using the bilayer scaffold within the microfluidic flow loop to reproduce the fluid flow associated with both tubular flow and resorption ensuring a physiologically accurate model of the tubule. This model was evaluated for cell viability, resorption and establishment of barrier function to further validate the physiological function. Finally, we expect to be able to reproduce effects of drugs known to have low, intermediate and high levels of toxicity using our model and will confirm that this model can be used for pre-clinical evaluation of new drugs.
Funding
- NIDDK Support