title: Stable expression of shRNAs in human CD34+ progenitor cells can avoid induction of interferon responses to siRNAs in vitro.
abstract: RNA interference occurs when cytoplasmic small interfering RNAs (siRNAs) enter the RNA-induced silencing complex and one strand guides cleavage of the target RNA by the Argonaute 2 protein. A significant concern when applying siRNAs or expressing small hairpin RNAs (shRNAs) in human cells is activation of the interferon (IFN) response. Synthetic siRNAs harboring certain motifs can induce an immune response when delivered to mouse and human immune cells such as peripheral blood mononuclear cells, monocytes, plasmacytoid dendritic cells (pDCs) and nonplasmacytoid dendritic cells (mDCs). In the present study we have tested the immunostimulatory effects of lipid-delivered siRNAs versus Pol III promoter-expressed shRNAs in primary CD34+ progenitor-derived hematopoietic cells. We show that in this system, lipid-delivered siRNAs are potent inducers of IFNalpha and type I IFN gene expression, whereas the same sequences when expressed endogenously are nonimmunostimulatory.
authors.affiliation: Division of Molecular Biology, Beckman Research Institute, City of Hope, Duarte, California 91010, USA.
authors.forename: Marjorie A
authors.initials: MA
authors.lastname: Robbins
authors.forename: Mingjie
authors.initials: M
authors.lastname: Li
authors.forename: Irene
authors.initials: I
authors.lastname: Leung
authors.forename: Haitang
authors.initials: H
authors.lastname: Li
authors.forename: Doris V
authors.initials: DV
authors.lastname: Boyer
authors.forename: Yong
authors.initials: Y
authors.lastname: Song
authors.forename: Mark A
authors.initials: MA
authors.lastname: Behlke
authors.forename: John J
authors.initials: JJ
authors.lastname: Rossi
mesh_terms: D018952:Antigens, CD34 / Q000096:biosynthesis*; D002469:Cell Separation; D003713:Dendritic Cells / Q000166:cytology; D005434:Flow Cytometry; D005821:Genetic Techniques; D006801:Humans; D066298:In Vitro Techniques; D007372:Interferons / Q000378:metabolism; D008055:Lipids / Q000737:chemistry; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism*; D013234:Stem Cells / Q000378:metabolism*; D014162:Transfection
chemical_list: D018952:Antigens, CD34; D008055:Lipids; D034741:RNA, Small Interfering; D007372:Interferons