title: Effective treatment of psoriasis with narrow-band UVB phototherapy is linked to suppression of the IFN and Th17 pathways.
abstract: Narrow-band ultraviolet-B (NB-UVB) phototherapy is an effective treatment for psoriasis. The molecular mechanisms underlying its efficacy are incompletely understood. To identify NB-UVB-induced molecular pathways that may account for its anti-inflammatory efficacy, gene expression profiling was performed using epidermal RNA from lesional and nonlesional skin from patients with psoriasis undergoing NB-UVB therapy. Downregulation of Th17 signaling pathway was observed during NB-UVB therapy in psoriatic epidermis. Strong inhibition of the Th17 pathway by UVB was confirmed in an ex vivo organ culture system by demonstrating reduced signal transducer and activator of transcription 3 (STAT3) phosphorylation and β-defensin-2 production. These results were further substantiated by demonstrating that NB-UVB inhibited the Th17-dependent psoriasis-like dermatitis in mice. Other pathways affected by NB-UVB therapy include the IFN signaling pathway, epidermal differentiation, and other well-known therapeutic targets in psoriasis, such as the glucocorticoid, vitamin D, peroxisome proliferator-activated receptor, and IL-4 signaling pathways. In conclusion, clinical improvement of psoriasis by NB-UVB is linked to suppression of Th17 and type I and type II IFN signaling pathways, which are critical in the pathogenesis of the disease. Our results show that clinically effective NB-UVB therapy is based on suppression of a broad range of important molecular pathways in psoriatic skin.
authors.affiliation: Department of Dermatology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands. e.racz@erasmusmc.nl
authors.forename: Emoke
authors.initials: E
authors.lastname: Rácz
authors.forename: Errol P
authors.initials: EP
authors.lastname: Prens
authors.forename: Dorota
authors.initials: D
authors.lastname: Kurek
authors.forename: Marius
authors.initials: M
authors.lastname: Kant
authors.forename: Dick
authors.initials: D
authors.lastname: de Ridder
authors.forename: Sabine
authors.initials: S
authors.lastname: Mourits
authors.forename: Ewout M
authors.initials: EM
authors.lastname: Baerveldt
authors.forename: Zeliha
authors.initials: Z
authors.lastname: Ozgur
authors.forename: Wilfred F J
authors.initials: WF
authors.lastname: van IJcken
authors.forename: Jon D
authors.initials: JD
authors.lastname: Laman
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Staal
authors.forename: Leslie
authors.initials: L
authors.lastname: van der Fits
mesh_terms: D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D061067:Antibodies, Monoclonal, Humanized; D002454:Cell Differentiation; D004817:Epidermis / Q000378:metabolism / Q000473:pathology; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007372:Interferons / Q000037:antagonists & inhibitors* / Q000502:physiology; D008297:Male; D008875:Middle Aged; D011565:Psoriasis / Q000378:metabolism / Q000473:pathology / Q000532:radiotherapy*; D015398:Signal Transduction / Q000502:physiology*; D058504:Th17 Cells / Q000502:physiology*; D014467:Ultraviolet Therapy; D000069549:Ustekinumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D007372:Interferons; D000069549:Ustekinumab