Enhancing between-facility reproducibility of the SH test as an <i>in vitro</i> skin sensitization test by the improved test method

There has been an increased demand to eliminate animal experiments and replace the with alternative tests for assessing safety of cosmetics. The SH test is in vitro skin sensitization that evaluates protein binding abilities a substance. Skin must be evaluated by multiple methods. uses same cell line measuring instruments as human Cell-Line Activation Test (h-CLAT), which one methods used evaluate different key events listed OECD guidelines. are cost advantages usher into facilities already running h-CLAT. conducted only at facility developed because studies on between-facility reproducibility validity have not performed. Therefore, verify transferability between-facilities reproducibility, we results three facilities, including development facility. After initial round testing, protocol was refined follows improve among facilities: i) determine optimum pH range, ii) change maximum applicable concentration water-soluble substances, iii) define appropriate dispersion conditions evaluating hydrophobic substances. These refinements markedly enhanced (from 76.0% 96.0%) 25 substances this study. This study confirmed effective method high technical reproducibility.