ABSTRACT
Sensitive skin is classically a self-described condition, clinically diagnosed based on patient's history and symptoms. This chapter reviews toxicological methods to study the effect of environmental, physical, or chemical elements affecting skin in dermatoses that can share similar symptoms. In the absence of in vitro validated models, the predictive testing for skin sensitization potential currently has relied on animal testing. In vitro assays such as direct peptide reactivity assay (DPRA) and the KeratinoSens have been validated for classifying a substance as a skin sensitizer. Buehler's occluded path test and Magnusson and Kligman's Guinea pig maximization test have been used for years; both tests measure sensitization as well as elicitation reactions. Local lymph node assay (LLNA) studies the induction phase of skin sensitization; skin sensitizers are identified by their ability to provoke proliferative responses in the mouse local lymph node. Photoallergy occurs when certain photoreactive allergens in the skin absorb light and create an inflammatory response.
