PROTEOMIC ANALYSIS OF THE RESPONSE OF EPIDERM™ CULTURES TO SODIUM LAURYL SULPHATE.

• TR Number: 397
• Keywords: 2D-gel electrophoresis, Allergic reactions, Cytotoxicity, ECVAM, ELISA, EpiDerm, HS1, In vitro alternatives, Involucrin, MTT, MTT assay, Peroxiredoxin 1, Proteomic analysis, Proteomicis, Rapid test system, Serine protease inhibitor, Skin irritation, Skin irritation mechanisms, Sodium lauryl sulphate (SLS), Western blotting

This study by researchers at Unilever’s Safety and Environmental Assurance Centre (SEAC) demonstrated how Mattek’s EpiDerm in vitro human skin tissue equivalent was used to identify a number of proteins that could be used as general markers for skin irritation. Scientists at Unilever’s Safety and Environmental Assurance Centre (UK) performed an analysis of EpiDerm™ cultures treated with the known skin irritant sodium lauryl sulphate (SLS) using 2D-gel electrophoresis in order to understand the mechanism of action and thereby identify novel markers of skin irritation. A range of both broad and narrow pH gradient first-dimension gels were run (pH 4-7, 6-11, 4-5, 5-6 and 6-9) consistently followed by 12% SDS-PAGE in the second dimension. Following treatment of EpiDerm with SLS, 67 proteins of interest were identified, of which 8 were selected as interesting: calmodulin-like skin protein, involucrin, epithelial cell marker protein, HS1, per-oxiredoxin 1, serine protease inhibitor, KIAA0117 and ribosomal protein L17. Involucrin was confirmed as being up-regulated by both ELISA and Western blotting. The use of proteomics and EpiDerm human skin tissue equivalents identified a number of proteins which could be used as general markers for skin irritation, and which may in particular be of value for the development of in vitro predictive models.