Direct skin contact with chemical or physical substances is predisposed
to allergic contact dermatitis (ACD), in which the skin contact area
develops various allergic reactions. ACD can be triggered by extremely
complicated adverse outcome pathways. A variety of non-animal in vitro
tests such as direct peptide reactivity assay (DPRA), KeratinoSens™,
human cell line activation test (h-CLAT), U-SENSTM, and SENS-IS based on
different mechanisms have been developed to identify the sensitizers.
Additionally, a broad spectrum of in silico models to predict skin
sensitization have emerged based on various animal and non-animal data
using assorted modeling schemes.