Replacing the Draize eye test: Impedance spectroscopy as a 3R method to discriminate between all GHS categories for eye irritation

Abstract

Highly invasive animal based test procedures for risk assessment such as the Draize eye test are under increasing criticism due to poor transferability for the human organism and animal-welfare concerns. However, besides all efforts, the Draize eye test is still not completely replaced by alternative animal-free methods. To develop an in vitro test to identify all categories of eye irritation, we combined organotypic cornea models based on primary human cells with an electrical readout system that measures the impedance of the test models. First, we showed that employing a primary human cornea epithelial cell based model is advantageous in native marker expression to the primary human epidermal keratinocytes derived models. Secondly, by employing a non-destructive measuring system based on impedance spectroscopy, we could increase the sensitivity of the test system. Thereby, all globally harmonized systems categories of eye irritation could be identified by repeated measurements over a period of 7 days. Based on a novel prediction model we achieved an accuracy of 78% with a reproducibility of 88.9% to determine all three categories of eye irritation in one single test. This could pave the way according to the 3R principle to replace the Draize eye test.

Preparation of Phosphorescent Eu2+, Dy3+‐Doped Strontium Aluminate Nanoparticles by Laser Vaporization for the Modification of Therapeutic Contact Lenses

“…Generation of 3D Cornea-like Models: Modified reconstructed human epidermis (mRHE) tissue models were used as cornea-like models, as published by seeding hEK on cell culture inserts with polycarbonate membrane (0.4 μm pore size, Brand, Wertheim, Germany) at a density of 1 Â 10 6 /mL in Epilife with 300 μL/insert. [44] Tissue models were exposed to the air-liquid interface 24 h upon model setup and culture medium was changed to a high-calcium air-liquid interface medium. mRHE models were cultured for 11 days for the application of an EIT.…”

“…The barrier integrity was measured at a frequency of 1000 Hz (transepithelial electrical resistance [TEER] 1000 Hz ). [43,44] TEER 1000Hz values were normalized to the NC of respective culture days. Repeated impedance measurements of LAVA Ar-treated mRHE resulted in a continuous level above 60% (Figure 4e).…”

Tissue Models for Neisseria gonorrhoeae Research—From 2D to 3D

“…However, these models were not made with infection research in mind. Instead, diverse efforts were taken to replace the in vivo Draize test of eye irritation (Lotz et al, 2016;Lotz et al, 2018), generate 3D corneal models to use them as grafts in transplant medicine (Sharif et al, 2018), and for investigating specific pathologic conditions such as Keratoconus (Karamichos et al, 2012) or dry-eye disease (Park et al, 2018;Kaluzhny et al, 2020). On the other hand, adaptation and usage of these alreadyexisting models in gonococcal research might provide new insights into the pathology of eye infection with N. gonorrhoeae.…”

Development and evaluation of a quality control system based on transdermal electrical resistance for skin barrier function in vitro

“…24 Lotz et al demonstrate a more sensitive in vitro test system on cornea epithelium, that allows identification of small barrier changes, by employing an impedance spectroscopy. 25 However, it is questionable if the transferability to more lipophilic molecules is guaranteed. The relationship between resistance data and permeability coefficient data of three physicochemical different permeants showed good linear correlations for the hydrophilic compounds urea (R 2 : 0.939) and mannitol (R 2 : 0.745), respectively.…”