title: Oligonucleotides suppress IL-8 in skin keratinocytes in vitro and offer anti-inflammatory properties in vivo.
abstract: DNA codes for genetic information. Furthermore, recent findings suggest that DNA offers additional function, particularly in the recognition of microorganisms. In this study, we investigated two classes of oligodeoxynucleotides (ODN) in skin keratinocytes; namely, an ODN comprising two cytidine-phosphate-guanosine (CpG) motifs (CpG-1-phosphorothioate (PTO)) and a poly-cytidine (Non-CpG-5-PTO) as control. Both fluorescence-tagged ODN were rapidly taken up by cells and accumulated already after 5 minutes in perinuclear compartments. In order to test whether ODN convey immunological effects in keratinocytes, secretion of IL-8 was measured. Interestingly, both CpG-1-PTO and Non-CpG-5-PTO suppressed basal and tumor necrosis factor alpha-induced IL-8 levels measured in cell culture supernatants. Experiments using deletion mutant revealed a critical length of approximately 16 nucleotides conveying IL-8 suppression. Studies regarding the ODN backbone offered that PTO bondings are critical for significant IL-8 suppression. In order to substantiate the anti-inflammatory response, a contact hypersensitivity mouse model was utilized. Topical application of Non-CpG-5-PTO-containing ointments reduced ear thickness in sensitized mice. Taken together, these findings suggest an anti-inflammatory effect of ODN in epithelial cells in vitro and in vivo, indicating that DNA molecules offer distinct biological activities restricted to the physiological compartment applied. This effect seems to be independent from Toll-like receptor 9.
authors.affiliation: Department of Dermatology and Venerology, J.W. Goethe-University, Frankfurt/Main, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Dorn
authors.forename: Ralf Joachim
authors.initials: RJ
authors.lastname: Ludwig
authors.forename: Andreas
authors.initials: A
authors.lastname: Bock
authors.forename: Diamant
authors.initials: D
authors.lastname: Thaci
authors.forename: Katja
authors.initials: K
authors.lastname: Hardt
authors.forename: Jurgen
authors.initials: J
authors.lastname: Bereiter-Hahn
authors.forename: Roland
authors.initials: R
authors.lastname: Kaufmann
authors.forename: August
authors.initials: A
authors.lastname: Bernd
authors.forename: Stefan
authors.initials: S
authors.lastname: Kippenberger
mesh_terms: D000287:Administration, Topical; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D002460:Cell Line; D003199:Computer Systems; D018899:CpG Islands / Q000235:genetics; D004247:DNA / Q000096:biosynthesis; D019175:DNA Methylation; D003877:Dermatitis, Contact / Q000517:prevention & control; D004431:Ear, External / Q000187:drug effects / Q000276:immunology; D005799:Genes, Dominant; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000517:prevention & control; D016209:Interleukin-8 / Q000037:antagonists & inhibitors*; D015603:Keratinocytes / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D053594:Myeloid Differentiation Factor 88 / Q000235:genetics; D009838:Oligodeoxyribonucleotides / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D051217:Toll-Like Receptor 9 / Q000235:genetics; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D000893:Anti-Inflammatory Agents; C408982:CPG-oligonucleotide; C518599:CpG-1-phosphorothioate; D016209:Interleukin-8; D053594:Myeloid Differentiation Factor 88; D009838:Oligodeoxyribonucleotides; D051217:Toll-Like Receptor 9; C518598:non-CpG-5-phosphorothioate; D004247:DNA; D007770:L-Lactate Dehydrogenase