title: Guanine-modified inhibitory oligonucleotides efficiently impair TLR7- and TLR9-mediated immune responses of human immune cells.
abstract: Activation of TLR7 and TLR9 by endogenous RNA- or DNA-containing ligands, respectively, is thought to contribute to the complicated pathophysiology of systemic lupus erythematosus (SLE). These ligands induce the release of type-I interferons by plasmacytoid dendritic cells and autoreactive antibodies by B-cells, both responses being key events in perpetuating SLE. We recently described the development of inhibitory oligonucleotides (INH-ODN), which are characterized by a phosphorothioate backbone, a CC(T)XXX3-5GGG motif and a chemical modification of the G-quartet to avoid the formation of higher order structures via intermolecular G-tetrads. These INH-ODNs were equally or significantly more efficient to impair TLR7- and TLR9-stimulated murine B-cells, macrophages, conventional and plasmacytoid dendritic cells than the parent INH-ODN 2088, which lacks G-modification. Here, we evaluate the inhibitory/therapeutic potential of our set of G-modified INH-ODN on human immune cells. We report the novel finding that G-modified INH-ODNs efficiently inhibited the release of IFN-α by PBMC stimulated either with the TLR7-ligand oligoribonucleotide (ORN) 22075 or the TLR9-ligand CpG-ODN 2216. G-modification of INH-ODNs significantly improved inhibition of IL-6 release by PBMCs and purified human B-cells stimulated with the TLR7-ligand imiquimod or the TLR9-ligand CpG-ODN 2006. Furthermore, inhibition of B-cell activation analyzed by expression of activation markers and intracellular ATP content was significantly improved by G-modification. As observed with murine B-cells, high concentrations of INH-ODN 2088 but not of G-modified INH-ODNs stimulated IL-6 secretion by PBMCs in the absence of TLR-ligands thus limiting its blocking efficacy. In summary, G-modification of INH-ODNs improved their ability to impair TLR7- and TLR9-mediated signaling in those human immune cells which are considered as crucial in the pathophysiology of SLE.
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Römmler
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Hammel
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Waldhuber
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, Germany.
authors.forename: Tina
authors.initials: T
authors.lastname: Müller
authors.affiliation: Miltenyi Biotec GmbH, Bergisch Gladbach, Germany.
authors.forename: Marion
authors.initials: M
authors.lastname: Jurk
authors.affiliation: Adiutide Pharmaceuticals GmbH, Frankfurt, Germany.
authors.forename: Eugen
authors.initials: E
authors.lastname: Uhlmann
authors.affiliation: Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Wagner
authors.affiliation: Nexigen GmbH, Köln, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Vollmer
authors.affiliation: Institute of Medical Microbiology and Hygiene, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Miethke
mesh_terms: D000328:Adult; D000818:Animals; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006147:Guanine / Q000737:chemistry*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism*; D008180:Lupus Erythematosus, Systemic / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008297:Male; D051379:Mice; D009838:Oligodeoxyribonucleotides / Q000737:chemistry / Q000494:pharmacology; D009841:Oligonucleotides / Q000737:chemistry* / Q000494:pharmacology*; D051199:Toll-Like Receptor 7 / Q000235:genetics / Q000378:metabolism*; D051217:Toll-Like Receptor 9 / Q000235:genetics / Q000378:metabolism* / Q000819:agonists; D055815:Young Adult
chemical_list: C513533:CpG ODN 2006; C526902:CpG ODN 2216; D015850:Interleukin-6; D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides; D051199:Toll-Like Receptor 7; D051217:Toll-Like Receptor 9; D006147:Guanine