Pulmonary Gene Silencing in Transgenic EGFP Mice Using Aerosolised Chitosan/siRNA Nanoparticles

• Published in: Pharmaceutical research Vol. 27; no. 12; pp. 2520 - 2527
• Main Authors: Nielsen, Ebbe J. B, Nielsen, Jan M, Becker, Daniel, Karlas, Alexander, Prakash, Hridayesh, Glud, Sys Z, Merrison, Jonathan, Besenbacher, Flemming, Meyer, Thomas F, Kjems, Jørgen, Howard, Kenneth A
• Format: Journal Article
• Language: English
• Published: Boston Boston : Springer US 01.12.2010; Springer US; Springer Nature B.V
• Subjects: aerosol; Aerosols; Alveoli; Animals; Base Sequence; Biochemistry; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedical materials; Biomedicine; Catheters; Cell Line; Chitosan; Diffraction; Flow Cytometry; Gene Knockdown Techniques; Gene Silencing; Gene therapy; Green Fluorescent Proteins - genetics; Lasers; Lung; Medical Law; Mice; Mice, Inbred C57BL; Mice, Transgenic; Nanoparticles; Pharmacology/Toxicology; Pharmacy; pulmonary gene silencing; Research Paper; Ribonucleic acid; RNA; RNA Interference; RNA-mediated interference; Rodents; siRNA; Trachea; Transgenic animals; Transgenic mice; chitosan; siRNA; nanoparticles; RNA interference; pulmonary gene silencing; aerosol
• ISSN: 0724-8741; 1573-904X
• DOI: 10.1007/s11095-010-0255-y

Purpose This work describes the production and application of an aerosolised formulation of chitosan nanoparticles for improved pulmonary siRNA delivery and gene silencing in mice. Methods Aerosolised chitosan/siRNA nanoparticles were pneumatically formed using a nebulising catheter and sized by laser diffraction. In vitro silencing of aerosolised and non-aerosolised formulations was evaluated in an EGFP endogenous-expressing H1299 cell line by flow cytometry. Non-invasive intratracheal insertion of the catheter was used to study nanoparticle deposition by histological detection of Cy3-labeled siRNA and gene silencing in transgenic EGFP mouse lungs using a flow cytometric method. Results Flow cytometric analysis demonstrated minimal alteration in gene silencing efficiency before (68%) and after (62%) aerosolisation in EGFP-expressing H1299 cells. Intratracheal catheter administration in mice resulted in nanoparticle deposition throughout the entire lung in both alveoli and bronchiolar regions using low amounts of siRNA. Transgenic EGFP mice dosed with the aerosolised nanoparticle formulation showed significant EGFP gene silencing (68% reduction compared to mismatch group). Conclusions This work provides a technology platform for effective pulmonary delivery and gene silencing of RNAi therapeutics with potential use in preclinical studies of respiratory disease treatment.