title: UVB radiation interrupts cytokine-mediated support of an epidermal-derived dendritic cell line (XS52) by a dual mechanism.
abstract: We have established long-term dendritic cell lines from the epidermis of newborn mice. These cell lines (XS series) proliferate maximally in response to granulocyte/macrophage-colony stimulating factor, as well as to CSF-1, which is produced by skin-derived NS fibroblast lines and by keratinocytes (albeit in smaller amounts). The purpose of this study was to examine the impact of UVB radiation on CSF-1-mediated interaction of dendritic cells with fibroblasts and keratinocytes. Exposure of NS cells to UVB radiation (unfiltered FS20 sunlamp) decreased CSF-1 production at mRNA and protein levels. Both changes occurred in a dose-dependent fashion, with 50 J/m2 causing a significant reduction. UVB radiation also downregulated CSF-1 mRNA expression by Pam 212 keratinocytes. UVB exposure of XS cells diminished the surface expression of CSF-1 receptors, with 50 J/m2 causing a significant reduction. Thus, UVB radiation interrupts CSF-1-mediated cell-cell interaction by a dual mechanism: downregulating CSF-1 production and abrogating CSF-1 receptor expression. Importantly, granulocyte/macrophage-colony stimulating factor receptor expression by XS cells was also inhibited by UVB radiation, once again, with 50 J/m2 producing significant inhibition. We propose that the resulting CSF-1 deficiency in epidermal microenvironment and unresponsiveness by dendritic cells to relevant growth factors may contribute to UVB-mediated loss of resident epidermal dendritic cells (i.e., Langerhans cells) in skin.
authors.affiliation: Department of Dermatology, University of Texas, Southwestern Medical Center, Dallas 75235-9069, USA.
authors.forename: G
authors.initials: G
authors.lastname: Schuhmachers
authors.forename: K
authors.initials: K
authors.lastname: Ariizumi
authors.forename: T
authors.initials: T
authors.lastname: Kitajima
authors.forename: D
authors.initials: D
authors.lastname: Edelbaum
authors.forename: S
authors.initials: S
authors.lastname: Xu
authors.forename: R K
authors.initials: RK
authors.lastname: Shadduck
authors.forename: G L
authors.initials: GL
authors.lastname: Gilmore
authors.forename: R S
authors.initials: RS
authors.lastname: Taylor
authors.forename: P R
authors.initials: PR
authors.lastname: Bergstresser
authors.forename: A
authors.initials: A
authors.lastname: Takashima
mesh_terms: D000818:Animals; D002460:Cell Line; D003713:Dendritic Cells / Q000378:metabolism / Q000528:radiation effects*; D016173:Macrophage Colony-Stimulating Factor / Q000235:genetics / Q000502:physiology*; D051379:Mice; D012333:RNA, Messenger / Q000032:analysis; D016186:Receptor, Macrophage Colony-Stimulating Factor / Q000528:radiation effects; D016187:Receptors, Granulocyte-Macrophage Colony-Stimulating Factor / Q000528:radiation effects; D014466:Ultraviolet Rays
chemical_list: D012333:RNA, Messenger; D016187:Receptors, Granulocyte-Macrophage Colony-Stimulating Factor; D016173:Macrophage Colony-Stimulating Factor; D016186:Receptor, Macrophage Colony-Stimulating Factor