title: Endogenous microRNA regulation suppresses transgene expression in hematopoietic lineages and enables stable gene transfer.
abstract: MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression by repressing translation of target cellular transcripts. Increasing evidence indicates that miRNAs have distinct expression profiles and play crucial roles in numerous cellular processes, although the extent of miRNA regulation is not well known. By challenging mice with lentiviral vectors encoding target sequences of endogenous miRNAs, we show the efficiency of miRNAs in sharply segregating gene expression among different tissues. Transgene expression from vectors incorporating target sequences for mir-142-3p was effectively suppressed in intravascular and extravascular hematopoietic lineages, whereas expression was maintained in nonhematopoietic cells. This expression profile, which could not be attained until now, enabled stable gene transfer in immunocompetent mice, thus overcoming a major hurdle to successful gene therapy. Our results provide novel in situ evidence of miRNA regulation and demonstrate a new paradigm in vector design with applications for genetic engineering and therapeutic gene transfer.
authors.affiliation: San Raffaele Telethon Institute for Gene Therapy (HSR-TIGET), via Olgettina 58, 20132 Milano, Italy.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Brown
authors.forename: Mary Anna
authors.initials: MA
authors.lastname: Venneri
authors.forename: Anna
authors.initials: A
authors.lastname: Zingale
authors.forename: Lucia
authors.initials: L
authors.lastname: Sergi Sergi
authors.forename: Luigi
authors.initials: L
authors.lastname: Naldini
mesh_terms: D000818:Animals; D019070:Cell Lineage; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D006412:Hematopoietic Stem Cells / Q000502:physiology*; D016086:Lentivirus / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008822:Mice, Transgenic; D035683:MicroRNAs / Q000378:metabolism*; D013154:Spleen / Q000166:cytology / Q000378:metabolism; D019076:Transgenes
chemical_list: D035683:MicroRNAs