Test No. 442D: In Vitro Skin Sensitisation
Assays addressing the Adverse Outcome Pathway Key Event on Keratinocyte activation
The present Key Event based Test Guideline addresses the human health hazard endpoint
skin sensitisation, following exposure to a test chemical. Skin sensitisation refers
to an allergic response following skin contact with a tested chemical, as defined
by the United Nations Globally Harmonized System of Classification and Labelling of
Chemicals (UN GHS). This Test Guideline is proposed to address a Key Event leading
to skin sensitisation, namely keratinocyte activation. This Key Event on the Adverse
Outcome Pathway (AOP) leading to skin sensitisation takes place in the keratinocytes
and includes inflammatory responses as well as gene expression associated with specific
cell signalling pathways such as the antioxidant/electrophile response element (ARE)-dependent
pathways. This Test Guideline provides three in vitro test methods addressing the
same Key Event on the AOP for skin sensitisation: (i) the ARE-Nrf2 luciferase KeratinoSens™
test method, (ii) the ARE-Nrf2 luciferase LuSens test method and (iii) the Epidermal
Sensitisation Assay – EpiSensA. The KeratinoSens and the Lusens are in vitro ARE-Nrf2
luciferase-based test methods and the EpiSensA is based on gene expression quantification
using Reverse Transcription- quantitative PCR in reconstructed human epidermis models.
The proposed test methods are used for supporting the discrimination between skin
sensitisers and non-sensitisers in accordance with the UN GHS. Performance standards
have been developed to enable the validation of similar test methods.
Published on June 25, 2024Also available in: French
In series:OECD Guidelines for the Testing of Chemicals, Section 4: Health Effectsview more titles