Analysis of interleukin-1alpha (IL-1alpha) and interleukin-8 (IL-8) expression and release in in vitro reconstructed human epidermis for the prediction of in vivo skin irritation and/or sensitization.
In the present study, reconstructed human epidermis (RHE) was used as an in vitro model to discriminate 1-chloro-2,4-dinitrobenzene (DNCB), nickel sulfate (NiSO(4)), oxazolone (OXA), 2,4-dinitrofluorobenzene (DNFB) and 2,4,6-trinitrobenzenesulfonic acid (TNBS) as skin sensitizers from benzalkonium chloride (BC), benzoic acid (BA) and sodium lauryl sulfate (SLS) as skin irritants. Our criteria were (a) the differential IL-1alpha and IL-8 synthesis and release (b) cytotoxicity assessment by MTT assay. When the RHE are topically treated with the sensitizers, very low levels of extra- and intracellular IL-1alpha are observed although they induce significant cytotoxicity. In contrast, they exhibit a sharp maximum of IL-8 release. In the presence of the tested irritants, we observe the inverse cytokine release profile, although they induce dose-dependent cytotoxicity profiles similar to those observed with the sensitizers. Finally, IL-1alpha mRNA upregulation is observed after topical application of both sensitizers and irritants, but only the latter significantly increase extracellular IL-1alpha. In conclusion, our results suggest that the associated determination of IL-8, with IL-1alpha, and MTT conversion are at least necessary to discriminate and classify, in a single assay, irritant and sensitizing agents and represent a potential in vitro alternative to two classical in vivo assays.
Coquette
A
A
Department of Biology, SGS Biopharma S.A., Vieux Chemin du Poète 10, B-1301, Wavre, Belgium. alain_coquette@sgs.com
Berna
N
N
Vandenbosch
A
A
Rosdy
M
M
De Wever
B
B
Poumay
Y
Y
D000287:Administration, Topical; D000826:Animal Testing Alternatives; D001681:Biological Assay / Q000379:methods; D015415:Biomarkers / Q000032:analysis*; D004396:Coloring Agents / Q000008:administration & dosage; D046508:Culture Techniques; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects*; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis* / Q000378:metabolism; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000378:metabolism; D007509:Irritants / Q000633:toxicity*; D011237:Predictive Value of Tests; D023422:Skin Irritancy Tests / Q000379:methods; D013778:Tetrazolium Salts / Q000008:administration & dosage; D013844:Thiazoles / Q000008:administration & dosage
D015415:Biomarkers; D004396:Coloring Agents; D007375:Interleukin-1; D016209:Interleukin-8; D007509:Irritants; D013778:Tetrazolium Salts; D013844:Thiazoles; C022616:thiazolyl blue