March 28, 2018
Alternative methods, including the validated 3T3 Neutral Red Uptake (NRU) Phototoxicity assay (OECD TG 432) may be used as a pre-clinical test to address phototoxicity. Currently, there are no validated alternative test methods to identify photoallergens; however, there are several validated alternative test methods to address skin sensitization, including the Direct Peptide Reactivity Assay (DPRA) (OECD 442C). To address photoallergy, we utilized the 3T3 Phototoxicity assay in combination with a modified photo-DPRA assay to determine if these assays were able to 1) identify compounds with phototoxicity potential and 2) discriminate between photoirritants and photoallergens.