title: Validation study of the in vitro skin irritation test with the LabCyte EPI-MODEL24.
abstract: A validation study on an in vitro skin irritation assay was performed with the reconstructed human epidermis (RhE) LabCyte EPI-MODEL24, developed by Japan Tissue Engineering Co. Ltd (Gamagori, Japan). The protocol that was followed in the current study was an optimised version of the EpiSkin protocol (LabCyte assay). According to the United Nations Globally Harmonised System (UN GHS) of classification for assessing the skin irritation potential of a chemical, 12 irritants and 13 non-irritants were validated by a minimum of six laboratories from the Japanese Society for Alternatives to Animal Experiments (JSAAE) skin irritation assay validation study management team (VMT). The 25 chemicals were listed in the European Centre for the Validation of Alternative Methods (ECVAM) performance standards. The reconstructed tissues were exposed to the chemicals for 15 minutes and incubated for 42 hours in fresh culture medium. Subsequently, the level of interleukin-1 alpha (IL-1 α) present in the conditioned medium was measured, and tissue viability was assessed by using the MTT assay. The results of the MTT assay obtained with the LabCyte EPI-MODEL24 (LabCyte MTT assay) demonstrated high within-laboratory and between-laboratory reproducibility, as well as high accuracy for use as a stand-alone assay to distinguish skin irritants from non-irritants. In addition, the IL-1α release measurements in the LabCyte assay were clearly unnecessary for the success of this model in the classification of chemicals for skin irritation potential.
authors.affiliation: Japanese Centre for the Validation of Alternative Methods, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku,Tokyo 158-8501, Japan. h-kojima@nihs.go.jp
authors.forename: Hajime
authors.initials: H
authors.lastname: Kojima
authors.forename: Yoko
authors.initials: Y
authors.lastname: Ando
authors.forename: Kenji
authors.initials: K
authors.lastname: Idehara
authors.forename: Masakazu
authors.initials: M
authors.lastname: Katoh
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kosaka
authors.forename: Etsuyoshi
authors.initials: E
authors.lastname: Miyaoka
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Shinoda
authors.forename: Tamie
authors.initials: T
authors.lastname: Suzuki
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: Isao
authors.initials: I
authors.lastname: Yoshimura
authors.forename: Atsuko
authors.initials: A
authors.lastname: Yuasa
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Takashi
authors.initials: T
authors.lastname: Omori
mesh_terms: D000826:Animal Testing Alternatives; D004817:Epidermis; D006801:Humans; D011786:Quality Control; D015203:Reproducibility of Results; D023422:Skin Irritancy Tests; D046509:Tissue Culture Techniques