title: Exposure to multiple doses of UVB radiation reduces the numbers of epidermal Langerhans cells and lymph node dendritic cells in mice.
abstract: Immune suppression following UVB irradiation is partly attributed to the effects of the exposure on antigen-presenting cells. Following a single UVB irradiation, there is a decrease in epidermal Langerhans cell numbers; this is accompanied by an increase in the number of dendritic cells (DC) in lymph nodes draining the irradiated site. We investigated whether a similar effect occurred following multiple UVB exposures. Mice were irradiated on their ears and shaved dorsal skin twice a week for 3 weeks. After the final exposure, the number of ATPase(+) Langerhans cells in epidermal sheets prepared from the ears was found to be decreased by 33% compared to unirradiated controls. The number of DC in the draining lymph nodes (DLN) did not increase as might have been expected; rather, a significant decrease of approximately 30% in DC numbers in the DLN of UVB-irradiated mice compared with unirradiated controls occurred. This decrease in antigen-presenting cells in both the epidermis and the DLN may be an important contributing factor to the immune suppression that follows multiple UVB exposures.
authors.affiliation: Medical Microbiology, University of Edinburgh Medical School, Teviot Place, Edinburgh, UKEH8 9AG.
authors.forename: Joanna C
authors.initials: JC
authors.lastname: Macve
authors.forename: Roddie C
authors.initials: RC
authors.lastname: McKenzie
authors.forename: Mary
authors.initials: M
authors.lastname: Norval
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000528:radiation effects; D003713:Dendritic Cells / Q000166:cytology / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D007801:Langerhans Cells / Q000166:cytology / Q000528:radiation effects*; D008198:Lymph Nodes / Q000166:cytology / Q000528:radiation effects*; D051379:Mice; D008809:Mice, Inbred C3H; D014466:Ultraviolet Rays