A CLASSIFICATION MODEL FOR ALLERGIC CONTACT-DERMATITIS

A classification model based on 36 compounds inducing allergic contact dermatitis and 36 non-allergens was developed by the discriminant tec hnique of two-value multiple regression analysis. One outlier was obse rved and several of the compounds fell in the indeterminate region bet ween the classes. Based on variable results of clinical data (human an d animal), some overlap in the model was considered more reasonable th an perfect separation. The descriptors in this model clearly imply int ercellular transport (LogP derived) and various forms of binding (Lond on forces [MR] and hydrogen-bonding [HBA, HBD]) as part of the allergi c contact dermatitis (ACD) response mechanism. In addition, substructu re descriptors related to the epidermal reactivity of the ACD inducers were statistically important. These include directly reactive functio nal groups from haptens and metabolizable precursor groups of prohapte ns. The model was developed from carefully selected compounds of diver se structure, representing a broad range of hapten and prohapten subst ructures without undue molecular complexity. Validation of the model i s in progress on a broad range of molecular structures far beyond thos e used in construction.