title: Differentiation of skin sensitizers from irritant chemicals by interleukin-1α and macrophage inflammatory protein-2 in murine keratinocytes.
abstract: The development of novel alternative testing methods is required to identify the sensitizing capacity of chemicals as a replacement for animal experimentation. We aimed to evaluate in vitro assays as screening tools for detecting skin sensitizers. The murine epidermal keratinocyte cell line HEL-30 was exposed to 16 relevant skin sensitizers and 6 skin irritants. The dose causing 75% cell viability (CV(75)) measured by an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was chosen as a highest dose and three more doses (0.5×, 0.1×, and 0.01× of CV(75)) were tested. As parameters, levels of interleukin 1α (IL-1α), macrophage inflammatory protein 2 (MIP-2), IL-6, and IL-18 production were measured using 4 different doses. The accuracy of detecting sensitizers or irritants by IL-1α or MIP-2 alone was exactly same: 75% (12 out of 16) for sensitizers, 83% (5 out of 6) for irritants, and overall 77% (17 out of 22). However, combination of IL-1α and MIP-2 showed better accuracy: 94% (15 out of 16), 67% (4 out of 6), and overall 86% (19 out of 22). IL-6 and IL-18 could not differentiate sensitizers from irritants. This study suggests that the combination of pro-inflammatory cytokines IL-1α and MIP-2 in murine HEL-30 cells can be a reliable in vitro method for identifying chemicals that may act as skin sensitizers.
authors.affiliation: Department of Microbiology and Immunology, Institute of Endemic Disease, College of Medicine, Seoul National University, Seoul 110-799, South Korea.
authors.forename: Dain
authors.initials: D
authors.lastname: Son
authors.forename: Yirang
authors.initials: Y
authors.lastname: Na
authors.forename: Wan-Seob
authors.initials: WS
authors.lastname: Cho
authors.forename: Byoung-Hee
authors.initials: BH
authors.lastname: Lee
authors.forename: Yong
authors.initials: Y
authors.lastname: Heo
authors.forename: Jae-Hak
authors.initials: JH
authors.lastname: Park
authors.forename: Seung Hyeok
authors.initials: SH
authors.lastname: Seok
mesh_terms: D000826:Animal Testing Alternatives / Q000379:methods*; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D054426:Chemokine CXCL2 / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects; D053582:Interleukin-1alpha / Q000235:genetics / Q000378:metabolism*; D007509:Irritants / Q000633:toxicity*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D008198:Lymph Nodes / Q000187:drug effects; D051379:Mice; D012867:Skin / Q000187:drug effects*
chemical_list: D054426:Chemokine CXCL2; C404915:Cxcl2 protein, mouse; D053582:Interleukin-1alpha; D007509:Irritants