Determinants of cytokine induction by small interfering RNA in human peripheral blood mononuclear cells.
Synthetic small interfering RNAs (siRNAs) can trigger a strong innate immune response in mammalian cells. This nonspecific side effect may hinder the application of siRNAs as tools in gene silencing. Chemically synthesized siRNAs, including traditional 19-mers with 2-nt 3' overhangs, longer duplexes with blunt or 3' overhangs, and asymmetric duplexes with a blunt end and a 2-nt 3' overhang, can evoke strong dose-dependent interferon-alpha (IFN-alpha) and tumor necrosis factor-alpha (TNF-alpha) release in human peripheral blood mononuclear cells (PBMCs). This response is independent of retinoic acid-inducible gene I but may involve endosomal toll-like receptors (TLRs). The immunostimulatory effect of the siRNAs is directly related to either or both of the strands of the duplex in a sequence-dependent manner. However, although some single-stranded RNAs and siRNAs potently evoked both IFN-alpha and TNF-alpha induction, these responses were not always coupled. In accordance with this, specific chemical modifications differentially altered cytokine production, suggesting recruitment of different TLRs in a sequence-dependent manner.
Zamanian-Daryoush
Maryam
M
Department of Cell Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
Marques
Joao T
JT
Gantier
Michael P
MP
Behlke
Mark A
MA
John
Matthias
M
Rayman
Patricia
P
Finke
James
J
Williams
Bryan R G
BR
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology*; D003593:Cytoplasm / Q000378:metabolism; D011992:Endosomes / Q000187:drug effects; D005909:Glioblastoma; D006801:Humans; D016898:Interferon-alpha / Q000096:biosynthesis / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D016328:NF-kappa B / Q000378:metabolism; D009690:Nucleic Acid Conformation / Q000187:drug effects; D011506:Proteins / Q000276:immunology / Q000378:metabolism; D016372:RNA, Antisense; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D016601:RNA-Binding Proteins; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D048868:Adaptor Proteins, Signal Transducing; D016207:Cytokines; C484290:IFIT1 protein, human; D016898:Interferon-alpha; D016328:NF-kappa B; D011506:Proteins; D016372:RNA, Antisense; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D014409:Tumor Necrosis Factor-alpha