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, Jones, Simon Wyn, Perry, Mark, Williams, Andrew Evan, Erjefalt, Jonas, Turner, John James, Barnes, Peter John, Sproat, Brian, Gait, Michael and Lindsay, Mark (2007) Lung delivery studies using siRNA conjugated to TAT(48-60) and penetratin reveal peptide induced reduction in gene expression and induction of innate immunity. Bioconjugate chemistry, 18 (5). pp. 1450-9. ISSN 1043-1802

Full text not available from this repository.

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.

Item Type:	Article
Subjects:	B200 Pharmacology, Toxicology and Pharmacy C700 Molecular Biology, Biophysics and Biochemistry
Department:	Faculties > Health and Life Sciences > Applied Sciences
Depositing User:	Sterghios Moschos
Date Deposited:	24 Oct 2016 08:59
Last Modified:	12 Oct 2019 17:30
URI:	http://nrl.northumbria.ac.uk/id/eprint/28144

Downloads