title: Digoxin and its derivatives suppress TH17 cell differentiation by antagonizing RORγt activity.
abstract: CD4(+) T helper lymphocytes that express interleukin-17 (T(H)17 cells) have critical roles in mouse models of autoimmunity, and there is mounting evidence that they also influence inflammatory processes in humans. Genome-wide association studies in humans have linked genes involved in T(H)17 cell differentiation and function with susceptibility to Crohn's disease, rheumatoid arthritis and psoriasis. Thus, the pathway towards differentiation of T(H)17 cells and, perhaps, of related innate lymphoid cells with similar effector functions, is an attractive target for therapeutic applications. Mouse and human T(H)17 cells are distinguished by expression of the retinoic acid receptor-related orphan nuclear receptor RORγt, which is required for induction of IL-17 transcription and for the manifestation of T(H)17-dependent autoimmune disease in mice. By performing a chemical screen with an insect cell-based reporter system, we identified the cardiac glycoside digoxin as a specific inhibitor of RORγt transcriptional activity. Digoxin inhibited murine T(H)17 cell differentiation without affecting differentiation of other T cell lineages and was effective in delaying the onset and reducing the severity of autoimmune disease in mice. At high concentrations, digoxin is toxic for human cells, but non-toxic synthetic derivatives 20,22-dihydrodigoxin-21,23-diol and digoxin-21-salicylidene specifically inhibited induction of IL-17 in human CD4(+) T cells. Using these small-molecule compounds, we demonstrate that RORγt is important for the maintenance of IL-17 expression in mouse and human effector T cells. These data indicate that derivatives of digoxin can be used as chemical templates for the development of RORγt-targeted therapeutic agents that attenuate inflammatory lymphocyte function and autoimmune disease.
authors: Molecular Pathogenesis Program, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, New York 10016, USA.
authors: Jun R
authors: JR
authors: Huh
authors: Monica W L
authors: MW
authors: Leung
authors: Pengxiang
authors: P
authors: Huang
authors: Daniel A
authors: DA
authors: Ryan
authors: Michael R
authors: MR
authors: Krout
authors: Raghu R V
authors: RR
authors: Malapaka
authors: Jonathan
authors: J
authors: Chow
authors: Nicolas
authors: N
authors: Manel
authors: Maria
authors: M
authors: Ciofani
authors: Sangwon V
authors: SV
authors: Kim
authors: Adolfo
authors: A
authors: Cuesta
authors: Fabio R
authors: FR
authors: Santori
authors: Juan J
authors: JJ
authors: Lafaille
authors: H Eric
authors: HE
authors: Xu
authors: David Y
authors: DY
authors: Gin
authors: Fraydoon
authors: F
authors: Rastinejad
authors: Dan R
authors: DR
authors: Littman
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000276:immunology / Q000473:pathology; D015551:Autoimmunity / Q000187:drug effects / Q000276:immunology; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D004077:Digoxin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use; D004330:Drosophila / Q000166:cytology; D006801:Humans; D020381:Interleukin-17 / Q000096:biosynthesis / Q000276:immunology; D051379:Mice; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D058504:Th17 Cells / Q000166:cytology* / Q000187:drug effects* / Q000276:immunology; D014158:Transcription, Genetic / Q000187:drug effects / Q000235:genetics
chemical_list: C558807:20,22-dihydrodigoxin-21,23-diol; D020381:Interleukin-17; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; C558808:digoxin-21-salicylidene; D004077:Digoxin