title: Ultraviolet light induces increased circulating interleukin-6 in humans.
abstract: Although the clinical effects of acute exposure to ultraviolet (UV) light--such as cutaneous inflammation, malaise, somnolence, chills and fever--have been appreciated many years, the underlying mechanisms mediating these effects are poorly understood. Interleukin-6 (IL-6) is a potent cytokine with a wide variety of biologic activities, including induction of fever and acute phase response. Because IL-6 is produced by keratinocytes in vivo and in vitro and because the release is enhanced by UV light, the present study was performed to investigate the effect of a single UV dose eliciting moderate to severe sunburn reaction on the production of IL-6 in vivo. Therefore, plasma of UV-treated human subjects was evaluated for IL-6 activity by testing its capacity to induce the proliferation of an IL-6-dependent hybridoma cell line (B9). In contrast to plasma samples obtained before UV exposure, post-UV-specimens contained significant levels of IL-6 peaking at 12 h after UV irradiation. Plasma IL-6 activity was neutralized by an antiserum directed against recombinant human IL-6, and upon HPLC gel filtration exhibited a molecular weight of around 20 kD. Moreover, plasma IL-6 levels correlated remarkably with fever course followed by an increase of acute phase proteins such as C-reactive protein. These data indicate that IL-6, which is released by keratinocytes following UV exposure, may gain access to the circulation and via its pyrogenic as well as acute phase-inducing effect may function as an important mediator of systemic sunburn reaction.
authors.affiliation: Department of Dermatology II, University of Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Urbanski
authors.forename: T
authors.initials: T
authors.lastname: Schwarz
authors.forename: P
authors.initials: P
authors.lastname: Neuner
authors.forename: J
authors.initials: J
authors.lastname: Krutmann
authors.forename: R
authors.initials: R
authors.lastname: Kirnbauer
authors.forename: A
authors.initials: A
authors.lastname: Köck
authors.forename: T A
authors.initials: TA
authors.lastname: Luger
mesh_terms: D000328:Adult; D002455:Cell Division / Q000528:radiation effects; D002460:Cell Line; D006358:Hot Temperature; D006801:Humans; D006825:Hybridomas / Q000166:cytology; D007106:Immune Sera / Q000276:immunology; D015850:Interleukin-6 / Q000097:blood* / Q000528:radiation effects; D008297:Male; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D007106:Immune Sera; D015850:Interleukin-6