A dataset on 145 chemicals tested in alternative assays for skin sensitization undergoing prevalidation

Abstract

Skin sensitization is a key endpoint for cosmetic ingredients, with a forthcoming ban for animal testing in Europe. Four alternative tests have so far been submitted to ECVAM prevalidation: (i) MUSST and (ii) h-Clat assess surface markers on dendritic cell lines, (iii) the direct peptide reactivity assay (DPRA) measures reactivity with model peptides and (iv) the KeratinoSens(TM) assay which is based on detection of Nrf2-induced luciferase. It is anticipated that only an integrated testing strategy (ITS) based on a battery of tests might give a full replacement providing also a sensitization potency assessment, but this concept should be tested with a data-driven analysis. Here we report a database on 145 chemicals reporting the quantitative endpoints measured in a U937- test, the DPRA and KeratinoSens(TM) . It can serve to develop data-driven ITS approaches as we show in a parallel paper and provides a view as to the current ability to predict with in vitro tests as we are entering 2013. It may also serve as reference database when benchmarking new molecules with in vitro based read-across and find use as a reference database when evaluating new tests. The tests and combinations thereof were evaluated for predictivity, and overall a similar predictivity was found as before on three-fold smaller datasets. Analysis of the dose-response parameters of the individual tests indicates a correlation to sensitization potency. Detailed analysis of chemicals false-negative and false-positive in two tests helped to define limitations in the tests but also in the database derived from animal studies.

In Vitro Approaches for Detection of Chemical Sensitization

“…This choice allows for the detection of the majority of reactive chemicals [14]. On a set of 145 chemicals, the DPRA was concordant with in vivo data in eight of 10 cases (sensitivity: 82%; specificity: 74%) [15]. Adding an incubation step with horseradish peroxidase and hydrogen peroxide provides a straightforward approach for detecting the peptide reactivity of pro-haptens [16].…”

Chlorbenzol [MAK Value Documentation in German language, 2018]

“…In vitro fanden sich negative Befunde im "Direct Peptide Reactivity Assay" sowie in den Zell-basierten Systemen des KeratinoSens-Assays, des U937-CD86-Tests (MUSST-Assay) (Natsch et al 2013) und im Hautmodell des SENS-IS-Systems (Cottrez et al 2016). Der "Human Cell Line Activation Test" (h-CLAT) ergab ein positives Ergebnis hinsichtlich der Aktivierung der CD86-Zellen, nicht aber der CD54-Zellen (Nukada et al 2011).…”

An economic approach to non-animal toxicity testing for skin sensitisation

“…"2 out of 3" ITS approach: (Bauch et al, 2012;Natsch et al, 2013;Urbisch et al, 2015a); Kao ITS and Kao STS: (Nukada et al, 2013;Takenouchi et al, 2015); RIVM STS:(van der Veen et al, 2014a;van der Veen et al, 2014b): Stacking meta model: (Gomes, 2012); IDS: (Matheson, 2015;Strickland et al, 2016); BN ITS: Jaworska et al, 2013;Jaworska et al, 2015); ANN ITS: (Hirota et al, 2013;Tsujita-Inoue et al, 2014;Hirota et al, 2015); EC-JRC: (Dimitrov et al, 2005;Asturiol et al, 2016); Global and local regression models: ; IATA: (Patlewicz et al, 2014, Patlewicz et al, 2015 was checked using the leave-one-out validation (Strickland et al, 2016). For the ANN-ITS, the ability of the model to predict the final decision outcome on the skin sensitisation potential was validated using the 10-fold cross validation approach (Hirota et al, 2013).…”

“…In case of deterministic approaches, the majority vote is frequently applied to test results without explicitly assessing uncertainties. Individual testing methods reproducibility, interchangeability and reliability is assessed for methods used in, for example, the "2 out of 3" ITS (Bauch et al, 2012;Natsch et al, 2013;Urbisch et al, 2015a) and the RIVM STS (van der Veen et al, 2014a;van der Veen et al, 2014b).…”

“…In the skin sensitisation AOP, the DPRA captures the first key event (protein binding), KeratinoSens TM and LuSens the second key event (epithelial responses), and the h-CLAT captures the third key event (dendritic cell activation; (OECD, 2012a)). Note that the cellular non-animal testing methods inherently cover cysteine reactivity and thus mechanistically overlap with the DPRA (Natsch et al, 2013).…”