PT - JOURNAL ARTICLE AU - Namho Kim AU - Gijung Kwak AU - Jason Rodriguez AU - Alessandra Livraghi-Butrico AU - Xinyuan Zuo AU - Valentina Simon AU - Eric Han AU - Siddharth Kaup Shenoy AU - Nikhil Pandey AU - Marina Mazur AU - Susan E Birket AU - Anthony Kim AU - Steven M Rowe AU - Richard Boucher AU - Justin Hanes AU - Jung Soo Suk TI - Inhaled gene therapy of preclinical muco-obstructive lung diseases by nanoparticles capable of breaching the airway mucus barrier AID - 10.1136/thoraxjnl-2020-215185 DP - 2022 Aug 01 TA - Thorax PG - 812--820 VI - 77 IP - 8 4099 - http://thorax.bmj.com/content/77/8/812.short 4100 - http://thorax.bmj.com/content/77/8/812.full SO - Thorax2022 Aug 01; 77 AB - Introduction Inhaled gene therapy of muco-obstructive lung diseases requires a strategy to achieve therapeutically relevant gene transfer to airway epithelium covered by particularly dehydrated and condensed mucus gel layer. Here, we introduce a synthetic DNA-loaded mucus-penetrating particle (DNA-MPP) capable of providing safe, widespread and robust transgene expression in in vivo and in vitro models of muco-obstructive lung diseases.Methods We investigated the ability of DNA-MPP to mediate reporter and/or therapeutic transgene expression in lung airways of a transgenic mouse model of muco-obstructive lung diseases (ie, Scnn1b-Tg) and in air–liquid interface cultures of primary human bronchial epithelial cells harvested from an individual with cystic fibrosis. A plasmid designed to silence epithelial sodium channel (ENaC) hyperactivity, which causes airway surface dehydration and mucus stasis, was intratracheally administered via DNA-MPP to evaluate therapeutic effects in vivo with or without pretreatment with hypertonic saline, a clinically used mucus-rehydrating agent.Results DNA-MPP exhibited marked greater reporter transgene expression compared with a mucus-impermeable formulation in in vivo and in vitro models of muco-obstructive lung diseases. DNA-MPP carrying ENaC-silencing plasmids provided efficient downregulation of ENaC and reduction of mucus burden in the lungs of Scnn1b-Tg mice, and synergistic impacts on both gene transfer efficacy and therapeutic effects were achieved when DNA-MPP was adjuvanted with hypertonic saline.Discussion DNA-MPP constitutes one of the rare gene delivery systems providing therapeutically meaningful gene transfer efficacy in highly relevant in vivo and in vitro models of muco-obstructive lung diseases due to its unique ability to efficiently penetrate airway mucus.All data relevant to the study are included in the article or uploaded as supplementary information.