Dataset Information

Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity.

ABSTRACT: The therapeutic application of siRNA shows promise as an alternative approach to small-molecule inhibitors for the treatment of human disease. However, the major obstacle to its use has been the difficulty in delivering these large anionic molecules in vivo. In this study, we have investigated whether siRNA-mediated knockdown of p38 MAP kinase mRNA in mouse lung is influenced by conjugation to the nonviral delivery vector cholesterol and the cell penetrating peptides (CPP) TAT(48-60) and penetratin. Initial studies in the mouse fibroblast L929 cell line showed that siRNA conjugated to cholesterol, TAT(48-60), and penetratin, but not siRNA alone, achieved a limited reduction of p38 MAP kinase mRNA expression. Intratracheal administration of siRNA resulted in localization within macrophages and scattered epithelial cells and produced a 30-45% knockdown of p38 MAP kinase mRNA at 6 h. As with increasing doses of siRNA, conjugation to cholesterol improved upon the duration but not the magnitude of mRNA knockdown, while penetratin and TAT(48-60) had no effect. Importantly, administration of the penetratin or TAT(48-60) peptides alone caused significant reduction in p38 MAP kinase mRNA expression, while the penetratin-siRNA conjugate activated the innate immune response. Overall, these studies suggest that conjugation to cholesterol may extend but not increase siRNA-mediated p38 MAP kinase mRNA knockdown in the lung. Furthermore, the use of CPP may be limited due to as yet uncharacterized effects upon gene expression and a potential for immune activation.

SUBMITTER: Moschos SA

PROVIDER: S-EPMC2621305 | biostudies-literature | 2007 Sep-Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity.

Moschos Sterghios Athanasios SA Jones Simon Wyn SW Perry Mark Michael MM Williams Andrew Evan AE Erjefalt Jonas Sten JS Turner John James JJ Barnes Peter John PJ Sproat Brian Stephen BS Gait Michael John MJ Lindsay Mark Andrew MA

Bioconjugate chemistry 20070821 5

The therapeutic application of siRNA shows promise as an alternative approach to small-molecule inhibitors for the treatment of human disease. However, the major obstacle to its use has been the difficulty in delivering these large anionic molecules in vivo. In this study, we have investigated whether siRNA-mediated knockdown of p38 MAP kinase mRNA in mouse lung is influenced by conjugation to the nonviral delivery vector cholesterol and the cell penetrating peptides (CPP) TAT(48-60) and penetra ...[more]

PMID: 17711319

Similar Datasets

Project description:BackgroundHepatitis B virus (HBV) infection is difficult to cure. HBV-specific immune tolerance plays a key role in HBV persistence, and enhancing cellular and humoral immunity will improve the control of HBV infection. The purpose of the study was to explore the anti-HBV and immunostimulatory effects of msiRNAs that introduce unpaired uridine bulges in the passenger strand.MethodsmsiRNAs targeting the HBV S and X genes were designed and named msiHBs and msiHBx, respectively. HepG2 cells were cotransfected with siRNA or msiRNA and the HBV replication-competent plasmid pHY106-wta or pHY106-X15. HepG2.215 cells were transfected with siRNA or msiRNA. The levels of HBsAg, HBeAg, and the cytokines TNF-α, IFN-α, IFN-β, IL-1α, and IL-6 in the culture supernatant was detected by ELISA. The levels of intracellular HBV RNA, nuclear HBV replication intermediates, and HBV DNA in the supernatant were measured by quantitative RT-PCR and PCR. The levels of HBV replication intermediates were detected by Southern blotting. Peripheral blood mononuclear cells were transfected with siRNA or msiRNA, and the levels of secreted cytokines IFN-α and IFN-β were detected by ELISA. The bioactivity of type I interferons in the supernatants was detected by the virus protection assay.ResultsmsiHBx treatment led to a significant decrease in HBsAg (to a negative level) and HBV DNA (95.5%) in the supernatant and intrahepatocellular HBV replication intermediates (89.8%) in HepG2 cells with transient HBV replication and in HepG2.2.15 cells. There was no significant difference between msiHBx and siHBx in terms of the reduction in HBV proteins and HBV replication (P > 0.05). Compared with siHBx, msiHBx treatment of HepG2 cells transfected with the HBV replication-competent plasmid led to a significant increase in the levels of the antiviral cytokines TNF-α (3.3-fold), IFN-α (1.4-fold), and IFN-β (2.5-fold) (P < 0.01), without upregulation of the proinflammatory cytokines IL-1α and IL-6. The virus protection assay results showed msiHBx-mediated type I interferons effectively protected L929 cells against ECMV infection.ConclusionsmsiHBx could effectively inhibit HBV expression and replication and induce an antiviral innate immune response without proinflammatory activation. The dual RNAi and immunostimulatory activity of msiRNAs may play an important role in the control of HBV infection.

Dataset Information

Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity.

Publications

Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets