Interleukin 12 production by monocytes from patients with psoriasis and its inhibition by ciclosporin A.
BACKGROUND
Psoriasis is a T-helper (Th)1 cytokine-mediated chronic skin disease and interleukin (IL)-12 has been shown to play a major role in the development of Th1 responses.


OBJECTIVE
To elucidate the role of IL-12 in the pathogenesis of psoriasis and to study the effect of ciclosporin A (CsA) on Th1 deviation of this disease.


METHODS
We investigated IL-12 production by stimulated monocytes from patients with psoriasis who were treated with or without CsA. Monocytes were stimulated with interferon-gamma plus lipopolysaccharide (LPS) or Staphylococcus aureus Cowan strain I (SAC). The amount of IL-12 p70 produced by stimulated monocytes was evaluated by enzyme-linked immunosorbent assay.


RESULTS
Compared with those from normal controls, LPS- but not SAC-stimulated monocytes from patients with psoriasis produced significantly higher amounts of IL-12. Interestingly, LPS-stimulated monocytes from patients with psoriasis treated with CsA produced significantly decreased amounts of IL-12 compared with those patients not treated with CsA.


CONCLUSIONS
Our results suggest that IL-12 production by monocytes may have a critical role in the pathogenesis of psoriasis, and that the therapeutic effect of CsA on psoriasis may be achieved by correcting the deviation of the Th1/Th2 balance.
Tada
Y
Y
Department of Dermatology, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
Asahina
A
A
Takekoshi
T
T
Kishimoto
E
E
Mitsui
H
H
Saeki
H
H
Komine
M
M
Tamaki
K
K
D000328:Adult; D002478:Cells, Cultured; D016572:Cyclosporine / Q000627:therapeutic use*; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007371:Interferon-gamma / Q000276:immunology; D018664:Interleukin-12 / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D011565:Psoriasis / Q000188:drug therapy / Q000276:immunology*; D011994:Recombinant Proteins; D015854:Up-Regulation / Q000276:immunology
D007166:Immunosuppressive Agents; D008070:Lipopolysaccharides; D011994:Recombinant Proteins; D018664:Interleukin-12; D007371:Interferon-gamma; D016572:Cyclosporine