title: p38 Mitogen-Activated protein kinase mediates dual role of ultraviolet B radiation in induction of maturation and apoptosis of monocyte-derived dendritic cells.
abstract: Although ultraviolet B (UVB) induces apoptosis and functional perturbations in dendritic cells (DC), for example, Langerhans cells (LC), it also stimulates some LC into maturation after irradiation in vivo. To analyze its reciprocal effects on DC, we elucidated the direct effect of UVB on DC in vitro using human monocyte-derived DC (MoDC). UVB from 50 to 200 J per m2 stimulated the maturation of MoDC with (1) augmented expression of CD86 and HLA-DR, (2) enhanced production of IL-1beta, IL-6, IL-8, and TNF-alpha at both the mRNA and protein levels, and (3) enhanced allostimulatory capacity on a per-cell basis, whereas the exceeded doses induced apoptotic cell death. Western-blot analysis of MoDC after UVB demonstrated a concentration-dependent phosphorylation of p38- and c-JUN N-terminal kinase (JNK)-mitogen-activated protein kinases (MAPK), but not that of extracellular signal-regulated kinases. p38 MAPK-inhibitor, SB203580, inhibited both UVB-induced maturation and apoptosis of MoDC. Interestingly, MoDC that had undergone apoptosis exhibited an augmented expression of HLA-DR without upregulation of CD86 antigen, suggesting their tolerogenic phenotype. Thus, our study revealed a dual effect of UVB, to stimulate maturation or to induce apoptosis in MoDC, depending on the dosage, via p38 MAPK pathway.
authors.affiliation: Department of Dermatology, Tohoku University Graduate School of Medicine, Sendai, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakagawa
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Ohtani
authors.forename: Masato
authors.initials: M
authors.lastname: Mizuashi
authors.forename: Zia U A
authors.initials: ZU
authors.lastname: Mollah
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Ito
authors.forename: Hachiro
authors.initials: H
authors.lastname: Tagami
authors.forename: Setsuya
authors.initials: S
authors.lastname: Aiba
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000502:physiology / Q000528:radiation effects*; D002454:Cell Differentiation / Q000502:physiology / Q000528:radiation effects; D002455:Cell Division / Q000276:immunology / Q000528:radiation effects; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology* / Q000201:enzymology / Q000528:radiation effects*; D006801:Humans; D066298:In Vitro Techniques; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009000:Monocytes / Q000166:cytology; D012333:RNA, Messenger / Q000378:metabolism; D012867:Skin / Q000166:cytology / Q000201:enzymology / Q000528:radiation effects; D013601:T-Lymphocytes / Q000166:cytology; D014158:Transcription, Genetic / Q000528:radiation effects; D014466:Ultraviolet Rays / Q000009:adverse effects*; D015854:Up-Regulation / Q000528:radiation effects; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D016207:Cytokines; D012333:RNA, Messenger; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases