2018-11, Messner, Catherine, Mauch, Linda, Mannino, Salvatore, Prestigiacomo, Vincenzo, Suter-Dick, Laura

2018-11, Suter-Dick, Laura

2018-09, Gaiser, Carine, Weston, Anna, Suter-Dick, Laura

2018-07, Suter-Dick, Laura, Gaiser, Carine

2018-11, Suter-Dick, Laura

2018-10, Messner, Catherine, Prestigiacomo, Vincenzo, Mannino, Salvatore, Mauch, Linda, Suter-Dick, Laura

2018-08, Vormann, Marianne K., Gijzen, Linda, Hutter, Simon, Boot, Lisette, Nicolas, Arnaud, van den Heuvel, Angelique, Vriend, Jelle, Ng, Chee Ping, Nieskens, Tom T.G., van Duinen, Vincent, de Wagenaar, Bjorn, Masereeuw, Rosalinde, Suter-Dick, Laura, Trietsch, Sebastian J., Wilmer, Martijn, Joore, Jos, Vulto, Paul, Lanz, Henriette

Proximal tubules in the kidney play a crucial role in reabsorbing and eliminating substrates from the body into the urine, leading to high local concentrations of xenobiotics. This makes the proximal tubule a major target for drug toxicity that needs to be evaluated during the drug development process. Here, we describe an advanced in vitro model consisting of fully polarized renal proximal tubular epithelial cells cultured in a microfluidic system. Up to 40 leak-tight tubules were cultured on this platform that provides access to the basolateral as well as the apical side of the epithelial cells. Exposure to the nephrotoxicant cisplatin caused a dose-dependent disruption of the epithelial barrier, a decrease in viability, an increase in effluent LDH activity, and changes in expression of tight-junction marker zona-occludence 1, actin, and DNA-damage marker H2A.X, as detected by immunostaining. Activity and inhibition of the efflux pumps P-glycoprotein (P-gp) and multidrug resistance protein (MRP) were demonstrated using fluorescence-based transporter assays. In addition, the transepithelial transport function from the basolateral to the apical side of the proximal tubule was studied. The apparent permeability of the fluorescent P-gp substrate rhodamine 123 was decreased by 35% by co-incubation with cyclosporin A. Furthermore, the activity of the glucose transporter SGLT2 was demonstrated using the fluorescent glucose analog 6-NBDG which was sensitive to inhibition by phlorizin. Our results demonstrate that we developed a functional 3D perfused proximal tubule model with advanced renal epithelial characteristics that can be used for drug screening studies.

2018-11, Yan, Lu, Zenker, Armin, Suter-Dick, Laura

2018-10, Suter-Dick, Laura

2018-07, Suter-Dick, Laura, Mauch, Linda, Caj, Michaela, Vormann, Marianne K., Hutter, Simon, Lanz, Henriette, Wilmer, Martijn, Ramp, Daniela, Masereeuw, Rosalinde, Vriend, Jelle

Drug-induced kidney injury is often observed in the clinics and can lead to long-term organ failure. In this work, we evaluated a novel in vitro system that aims at detecting whether compounds can cause renal proximal tubule damage in man. For this, we implemented organotypic cultures of human conditionally immortalized proximal tubule epithelial cells overexpressing the organic anion transporter 1 (ciPTEC-OAT1) in a three-channel OrganoPlate under microfluidic conditions. Cells were exposed to four known nephrotoxicants (cisplatin, tenofovir, cyclosporine A, and tobramycin). The effect on cell viability and NAG release into the medium was determined. A novel panel of four miRNAs (mir-21, mir-29a, mir-34a, and mir-192) was selected as potential biomarkers of proximal tubule damage. After nephrotoxicant treatment, miRNA levels in culture medium were earlier indicators than cell viability (WST-8 assay) and outperformed NAG for proximal tubule damage. In particular, mir-29a, mir-34a, and mir-192 were highly reproducible between experiments and across compounds, whereas mir-21 showed more variability. Moreover, similar data were obtained in two different laboratories, underlining the reproducibility and technical transferability of the results, a key requirement for the implementation of novel biomarkers. In conclusion, the selected miRNAs behaved like sensitive biomarkers of damage to tubular epithelial cells caused by several nephrotoxicity mechanisms. This biomarker panel, in combination with the 3D cultures of ciPTEC-OAT1 in the OrganoPlate, represents a novel tool for in vitro nephrotoxicity detection. These results pave the way for the application of miRNAs in longitudinal, time-course in vitro toxicity studies.