The KeratinoSens assay for skin sensitization testing was recommended by the European Union Reference Laboratory for Alternatives to Animal Testing (EURL ECVAM) of the European Commission's Joint Research Centre.
The assay uses activation of the Keap1-Nrf2- antioxidant/electrophile response element (ARE)-dependent pathway as a measure for the skin sensitization potential of chemicals.
Following independent evaluation by EURL ECVAM and scientific peer review by EURL ECVAM's Scientific Advisory Committee (ESAC), Givaudan’s test method is now recommended for further work and the assay's potential use within integrated approaches.
Extensive regulation
The recommendation from EURL ECVAM Recommendations, like all others before, has undergone extensive commenting by EU regulators, stakeholders from industry, animal welfare and academia (ESTAF), international partners and regulators (ICATM framework), as well as the general public.
This means that it will then facilitate scientific discussions at OECD in view of developing OECD Test Guidelines for skin sensitization.
The OECD Test Guidelines are a collection of the most relevant internationally agreed test methods used by government, industry and independent laboratories to determine the safety of chemicals and chemical preparations, including pesticides and industrial chemicals.
Background
Chemicals can cause the immunological sensitization of skin tissue leading, upon repeated exposure, to an allergic reaction.
Due the biological complexity of this effect, the intrinsic hazard and risk of chemicals to sensitize skin has been assessed by animal experiments in the past.
However, there is increasing knowledge on the key biological and physiological mechanisms underlying skin sensitization, supporting the development of mechanism-based in vitro assays; a focus that Givaudan has brought to light with the development of this test method.
For example, the Keap1-Nrf2- antioxidant/electrophile response element (ARE)-dependent pathway, honed in on in this instance, is a key signaling pathway regulating the response of skin cells to chemical stressors including sensitizers.