Chemical mediators in atopic dermatitis:: Involvement of leukotriene B4 released by a type I allergic reaction in the pathogenesis of atopic dermatitis

Background: The mediators produced from a type I allergic reaction have not get been able to explain the pathogenesis of atopic dermatitis (AD), Objective: The purpose of this study was to elucidate the involvement of leukotriene (LT) B-4 produced from a type I allergic reaction in the pathogenesis of AD. Method: The release of LTB4 was measured both in vitro, in passively sensitized and antigen-challenged human skin slices, as well as in vivo, in skin chambers on patients with AD. Results: LTB4 was released from in vitro human skin by stimulation of the antigen (54.9 +/- 14.6 pg/g wet weight of skin by antigen challenge and 28.0 +/- 11.1 pg/g in control skin, P <.002). Antigen-specific release of LTB4 and histamine was also observed in vivo in nonlesional skin from the patients with AD by using the skin chamber technique. Conclusion: LTB4 release during type I allergic reaction in human skin has been determined in vitro. The released LTB4 possibly contributes to cellular response at the acute inflammatory lesion of AD.