Implementation of an in vitro methodology for phototoxicity evaluation in a human keratinocyte cell line. (December 2019)

• Record Type: Journal Article
• Authors: Maciel, B.; Moreira, P.; Carmo, H.; Gonçalo, M.; Lobo, J.M. Sousa; Almeida, I.F.
• Is Part Of: Toxicology in vitro. Volume 61(2019)
• Publication Date: 2019-12
• Subjects: Phototoxicity -- 3T3 neutral red -- HaCaT keratinocytes; Toxicity testing -- In vitro -- Periodicals; Toxicology -- Periodicals; 615.9
• DOI: 10.1016/j.tiv.2019.104618
• Languages: English
• ISSNs: 0887-2333

Abstract

Abstract: To assess photoxicity, several in vitro methods using different cellular models have been developed for preclinical testing. Over prediction of the in vivo photosafety hazard has been however appointed. Herein, we describe the implementation and validation of an in vitro methodology for phototoxicity evaluation based on the 3T3 neutral red uptake phototoxicity test using the HaCaT human keratinocyte cell line, and UVA/UVB radiation. Known positive (5-methoxypsoralen, chlorpromazine, and quinine) and negative (acetyl salicylic acid, hexachlorophene, and sodium lauryl sulphate) controls were tested together with a set of chemical currently used in cosmetic/pharmaceutical formulations. Apart from the advantage of using a cell line of human origin, these cells were generally more resistant to the cytotoxic effects of the test substances relative to the 3T3 mouse fibroblasts when exposed to an UVA irradiation dose of 1.7 mW/cm 2 . Therefore, this HaCaT NRU assay provides a more realistic experimental model that overcomes the over/high sensitivity frequently noted with the 3T3 NRU assay and that is more consistent with the human in vivo situation. Using a more representative method can prevent time-consuming and expensive in vivo testing in both animal models and humans that can significantly delay the clinical development of new chemicals. Highlights: Implementation and validation of the HaCaT NRU in vitro methodology for phototoxicity evaluation The HaCaT human keratinocyte cell line is more resistant to the phototoxic effects relative to the 3T3 mouse fibroblasts. This more realistic experimental model overcomes the over/high sensitivity noted with the 3T3 NRU assay. Time-consuming and expensive in vivo phototoxicity testing in both animal models and humans can be prevented.