WP7.2: Improving in vitro/in vivo correlations – Nephrotoxicity

 

WP7.2 results, download the entire summary: Results WP7.2.pdf

The kidney is especially susceptible to toxicity because of its role in excreting compounds, which involves a high blood supply, concentrating, metabolizing and transporting compounds. The focus in WP7.2 was on developing in vitro assays which reflect the role of the kidneys in vivo based on functional parameters including transport and barrier function involving a transepithelial cell layer and transport.

 

For the measurement of nephrotoxicity, transepithelial resistance (TEER) was chosen as the functional assay and the LLC-PK1 proximal tubular cell line as the test system. The results of functional assay were compared to the results of a viability assay (alamar blue) under exactly the same experimental conditions and testing was carried out in the 96-well plate format for both assays.

 

The fifty seven reference chemicals (including some nephrotoxic) were tested and the overall results show that the TEER is a sensitive predictor of toxicity. Using the data obtained, the IC20, IC50 and IC80 for both assays for all chemicals tested were calculated where possible using the statistical analysis techniques available at present. TEER showed greater sensitivity for nephrotoxic chemicals compared to non-nephrotoxic chemicals. However, compounds requiring metabolism, such as diethylene glycol did not show toxicity at the highest concentration tested. The results indicate that the TEER functional assay is a very promising assay to detect nephrotoxicity in vitro and is a more sensitive than a viability assay.