ABSTRACT
Experience to date confirms that the local lymph node assay provides a reliable method for the identification of the majority of skin allergens and, in addition, offers a number of important advantages compared with guinea pig predictive tests. The assay is relatively rapid and costeffective, is unaffected by the color of the test material, and is largely uninfluenced by irritant properties. Unlike the more sensitive guinea pig tests, the local lymph node assay does not require the use of adjuvant. Activity in guinea pig methods is assessed normally by visual evaluation of challenge-induced erythema and/or edema in previously sensitized animals. In contrast to such subjective assessment, the local lymph node assay provides an objective endpoint. Finally, fewer animals are required and, as there is no requirement to elicit contact hypersensitivity reactions, the animals tested are subject to less trauma.
