In Vitro Skin Sensitisation: The FBS free ARE-Nrf2 Luciferase α-Sens® Test Method

The α-Sens® test method was developed to achieve a serum-free and simple operation procedure with high accuracy for the prediction of skin sensitizers. The α-Sens® employs a dual luciferase assay system to detect both antioxidant response element (ARE)-mediated transcriptional activity and cell viability to evaluate the KE-2 response, the keratinocyte activation of the AOP in the skin sensitization process. The α-Sens® cell line was originally developed as “α-Sens (without ®)”, the multi-clone cell system of PHK 16-0b cell line (immortalized human keratinocyte by HPV16 virus genome) stably transfected with two reporter constructs, Antioxidant response element (ARE) inducible Firefly luciferase gene for ARE response and Thymidine Kinase (TK) promoter-driven Renilla luciferase gene for cell viability measurement(Maeda et al., 2020). Therefore, the α-Sens can measure ARE-mediated activity and cell viability simultaneously with the same exposure sample. α-Sens was further improved by modifying the reporter gene construct and was established as a single clone cell system, “α-Sens® (with ®)