Murine auricular transepidermal water loss -- a novel approach for evaluating irritant skin reaction in mice.

UNLABELLED: The standard method for evaluating contact allergy in mice is the ear swelling technique. However, in experimental irritant contact dermatitis, the epidermal barrier disruption, that represents a predominant effect of irritants, cannot be assayed by this

METHOD: An appropriate method to evaluate barrier disruption is the measurement of transepidermal water loss (TEWL) but to date this has so far been possible only on the trunk of hairless or shaved mice. We therefore developed a new technique to measure the TEWL of mice ears (murine auricular TEWL: MATEWL). After patch testing with irritants and allergens, respectively, we found that the ear swelling method is most suitable for evaluating allergic skin reactions, whereas MATEWL is most appropriate for evaluating irritant skin reactions.