Background
Gene deficiency diseases where there is lack of functional protein, have found a potential cure in the form of mRNA therapy (Citation1) but major challenges for achieving higher bioavailability concerning mRNA based therapy are higher rate of degradation, reduced ability to cross cellular barriers and immunogenicity (Citation2) The advances in the field of nano-carriers and chemical modifications of mRNA bases and codon optimization have brought the mRNA based technology into therapeutics race; however, much more has to be achieved (Citation3, Citation4). Cystic Fibrosis, a common genetic disorder among Caucasians is caused due to genetic mutation which results in high rate of mortality and reduced life quality (Citation5, Citation6). Although, there has been huge progress since the cloning of CFTR and its delivery in plasmid form using viral vector, none has been proven efficient in restoring normal expression and function in human (Citation7, Citation8). Lung cells consists of myriad of cell types among which Alveolar Types (I and II) cells, Endothelial cells, Club cells and Epithelial cells are the major CFTR expressing cells (Citation9–12). CFTR channel protein restoration in these cells using mRNA can improve disease condition of Cystic Fibrosis patient significantly. Additionally, in the light of recent identification of Lung stem cells (Myoepithelial cells and Bronchio Alveolar Stem Cells) (Citation13–15), gene correction via sgRNA/Cas9 system could be also fruitful to target and repair stem cells.
Method
In this study, we have made an attempt to deliver chemically modified mRNA with the help of nano-carriers (Chitosan-coated PLGA, Cationic Nano Liposomes) to specific lung cells via intratracheal and intravenous instillations. The reporter mRNA delivery and protein expression (mKate2) in different cellular population is identified with the help of cellular markers using Flow Cytometry. The lung function (Forced Expired Volume0.1 and compliance) improvement is compared using FlexiVent® to understand the effectiveness of different nanoparticles and route of administration.
Results and Conclusion
The study helps in easy characterization and localization of delivered mRNA for gene supplementation therapy. Lung function improvement of Cftr–/– mice was observed upon mRNA delivery using nanoparticles (Citation16). Chitosan coated PLGA nano-carriers have shown deep lung cell delivery (Endothelial cells) of reporter protein. In addition, this model has the potential to aid the development of delivery system for treating Lung diseases via Gene correction or Gene supplementation.
Conflict of Interest
M.S.D.K. holds a patent on RNA modification (EP2459231B1). M.S.D.K. and A.K.M.A.H. hold a European patent on delivery of cmRNAhCFTR complexed with nanoparticles (17169561.2-1401).
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