Expression of interleukin-18 in murine contact hypersensitivity.
In this study, we made a mouse model for contact hypersensitivity (CH) using oxazolone as a contact allergen and examined the expression of interleukin-18 (IL-18) in the diseased skin sites at both mRNA and protein levels. In the kinetic study by semiquantitative RT-PCR, IL-18 mRNA was constitutively produced in normal murine skin but increased significantly at 12 h and peaked at 24 h in the ear skin of CH mice. A positive correlation was confirmed between the IL-18 mRNA signal and CH, as measured by mouse ear swelling response. Histologically, in situ hybridization showed that the IL-18 mRNA signal was weakly observed in the dermis but not the epidermis of normal skin, whereas the IL-18 mRNA signal was found intensively in the dermis, particularly in inflammatory cell areas. Using IL-18-specific antibody immunostaining, it was further found that IL-18 protein production had a histologic location similar to that of IL-18 mRNA in both normal and CH mice. The present study suggests that IL-18 may be implicated in the pathogenesis of murine CH.
Xu
B
B
Department of Environmental Medicine, Faculty of Medicine, Kagoshima University, Japan. xubaohui@med3.kufm.kagoshima-u.ac.jp
Aoyama
K
K
Yu
S
S
Kitani
A
A
Okamura
H
H
Kurimoto
M
M
Matsuyama
T
T
Matsushita
T
T
D000818:Animals; D000918:Antibody Specificity; D003877:Dermatitis, Contact / Q000378:metabolism*; D004195:Disease Models, Animal; D005260:Female; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D020382:Interleukin-18 / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000378:metabolism
D020382:Interleukin-18; D012333:RNA, Messenger