Validation Study on Five Cytotoxicity Assays by JSAAE - V. Details of the Crystal Violet Staining Assay

The inter-laboratory validation study on 5 cytotoxicity assays conducted by JSAAE has been described in the preceding articles. Presented here are precise data and the protocols for the crystal violet staining (CV) assay with two cell lines, namely, HeLa S3 (SC) which is common to the other 4 assays, and CHL which has been utilized widely in this assay. Hand-plotted dose-response curves revealed information that enables us to easily detect abnormal data files. Characteristics of data files from 14 laboratories were visualized in a Figure together with all the log(ED50) values. Very low OD590 values were found in negative controls of submitted data, suggesting the need to carefully examine whether the results of the assay fell within the linear dose-response range or not. High inter-laboratory reproducibility, therefore low inter-laboratory variation, was observed with both cell lines in the CV assay. Any influence of cell lines was not apparent in the tested chemicals except for cetylpyridinium chloride monohydrate. Results will supplement our understanding on the CV assay carried out in the large-scale inter-laboratory validation. Isogo-ku, Yokohama-shi 235, Japan Food Research Laboratories, 6-11-10 Nagayama, Tama-shi, Tokyo 206, Division of Radiation Medicine, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263, Hakko Electric Machine Works Co. Ltd., 3055 Togura, Togura-machi, Hanishina-gun, Nagano 389-08, Central Research Laboratory, Takasago International Co., 1-411 Nishiyawata, Hiratsuka-shi, Kanagawa 254, Japan