Increased circulating Th17 frequencies and serum IL-22 levels in patients with acute generalized exanthematous pustulosis.
OBJECTIVE
Acute generalized exanthematous pustulosis (AGEP) is a diffuse pustular disorder that usually begins in intertriginous folds with widespread erythema. The causes in the majority of the cases are drugs. T cells and interleukin (IL)-8 play roles in the development of AGEP, but the mechanism remains to be elucidated. We investigated the involvement of Th17 cells and their cytokine IL-22 in the pathogenesis.


METHODS
Three patients with AGEP were enrolled in this study. The percentages of IL-17(+) Th17 cells, interferon γ(+) T cells and IL-4(+) T cells were measured in the patients' peripheral blood lymphocytes by intracellular cytokine staining and flow cytometry. The concentration of IL-22 in the sera was measured by enzyme-linked immunosorbent assay.


RESULTS
The percentages of Th17 cells were markedly higher in all three patients than healthy control individuals. The frequencies of interferon γ(+) T cells were slightly high in the patients compared with the control, and there was no definite tendency in IL-4(+) T-cell frequencies. The concentration of IL-22 was remarkably high in all patients when compared with normal subjects with levels under detection.


CONCLUSIONS
Th17 cells and their produced cytokine IL-22 were elevated in the peripheral blood of patients with AGEP. As IL-17 and IL-22 cooperatively stimulate keratinocytes to produce IL-8, IL-8 may contribute to the accumulation of neutrophils in the lesional epidermis of AGEP.
Kabashima
R
R
Department of Dermatology, University of Occupational and Environmental Health, Yahatanishi-ku, Kitakyushu, Japan.
Sugita
K
K
Sawada
Y
Y
Hino
R
R
Nakamura
M
M
Tokura
Y
Y
D000328:Adult; D000368:Aged; D004797:Enzyme-Linked Immunosorbent Assay; D005076:Exanthema / Q000097:blood*; D005260:Female; D006801:Humans; D007378:Interleukins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D058504:Th17 Cells / Q000166:cytology*; D000097043:Interleukin-22
D007378:Interleukins; D000097043:Interleukin-22