title: Targeted delivery of small interfering RNA to human dendritic cells to suppress dengue virus infection and associated proinflammatory cytokine production.
abstract: Dengue is a common arthropod-borne flaviviral infection in the tropics, for which there is no vaccine or specific antiviral drug. The infection is often associated with serious complications such as dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), in which both viral and host factors have been implicated. RNA interference (RNAi) is a potent antiviral strategy and a potential therapeutic option for dengue if a feasible strategy can be developed for delivery of small interfering RNA (siRNA) to dendritic cells (DCs) and macrophages, the major in vivo targets of the virus and also the source of proinflammatory cytokines. Here we show that a dendritic cell-targeting 12-mer peptide (DC3) fused to nona-D-arginine (9dR) residues (DC3-9dR) delivers siRNA and knocks down endogenous gene expression in heterogenous DC subsets, (monocyte-derived DCs [MDDCs], CD34(+) hematopoietic stem cell [HSC])-derived Langerhans DCs, and peripheral blood DCs). Moreover, DC3-9dR-mediated delivery of siRNA targeting a highly conserved sequence in the dengue virus envelope gene (siFvE(D)) effectively suppressed dengue virus replication in MDDCs and macrophages. In addition, DC-specific delivery of siRNA targeting the acute-phase cytokine tumor necrosis factor alpha (TNF-alpha), which plays a major role in dengue pathogenesis, either alone or in combination with an antiviral siRNA, significantly reduced virus-induced production of the cytokine in MDDCs. Finally to validate the strategy in vivo, we tested the ability of the peptide to target human DCs in the NOD/SCID/IL-2Rgamma(-/-) mouse model engrafted with human CD34(+) hematopoietic stem cells (HuHSC mice). Treatment of mice by intravenous (i.v.) injection of DC3-9dR-complexed siRNA targeting TNF-alpha effectively suppressed poly(I:C)-induced TNF-alpha production by DCs. Thus, DC3-9dR can deliver siRNA to DCs both in vitro and in vivo, and this delivery approach holds promise as a therapeutic strategy to simultaneously suppress virus replication and curb virus-induced detrimental host immune responses in dengue infection.
authors.affiliation: Immune Disease Institute, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Sandesh
authors.initials: S
authors.lastname: Subramanya
authors.forename: Sang-Soo
authors.initials: SS
authors.lastname: Kim
authors.forename: Sojan
authors.initials: S
authors.lastname: Abraham
authors.forename: Jiahong
authors.initials: J
authors.lastname: Yao
authors.forename: Mukesh
authors.initials: M
authors.lastname: Kumar
authors.forename: Priti
authors.initials: P
authors.lastname: Kumar
authors.forename: Viraga
authors.initials: V
authors.lastname: Haridas
authors.forename: Sang-Kyung
authors.initials: SK
authors.lastname: Lee
authors.forename: Leonard D
authors.initials: LD
authors.lastname: Shultz
authors.forename: Dale
authors.initials: D
authors.lastname: Greiner
authors.forename: Manjunath
authors.initials: M
authors.lastname: N
authors.forename: Premlata
authors.initials: P
authors.lastname: Shankar
mesh_terms: D000818:Animals; D016207:Cytokines / Q000096:biosynthesis* / Q000276:immunology; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology / Q000821:virology; D003715:Dengue / Q000276:immunology / Q000628:therapy; D003716:Dengue Virus / Q000187:drug effects / Q000276:immunology; D018014:Gene Transfer Techniques; D006801:Humans; D008264:Macrophages / Q000166:cytology / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D009842:Oligopeptides / Q000235:genetics / Q000276:immunology; D010455:Peptides / Q000235:genetics / Q000378:metabolism; D011070:Poly I-C / Q000276:immunology; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology; D014779:Virus Replication / Q000187:drug effects
chemical_list: D016207:Cytokines; D009842:Oligopeptides; D010455:Peptides; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; C491427:nonaarginine; D011070:Poly I-C