Hydrogen-induced disruption of the airway mucus barrier enhances nebulized RNA delivery to reverse pulmonary fibrosis

Nebulized RNA therapies are well suited for treating respiratory diseases, in particular pulmonary fibrosis (PF); however, effective delivery remains challenging. In this study, we present a highly efficient aerosol inhalation system that enables high levels of in vivo transfection efficiency in lung macrophages, yielding durable responses against PF. First, we established a nose-only aerosol inhalation device integrated with a hydrogen supplement system. This setup enables the precise administration of lipid nanoparticles (LNPs) at a controlled low dose, while simultaneously delivering the optimal concentration of therapeutic hydrogen gas. We further developed a hybrid lipid NP (HNP) by hybridizing a pH-dependent charge-inverting lipid film with apoptotic T cell membranes to enhance endosomal escape and trigger macrophage production of hepatocyte growth factor for lung repair. We demonstrated that the hydrogen flow-induced shear stresses disrupt the NP-mucus interaction, enhancing the deposition of aerosolized HNPs/<i>TGF</i>β<i>1</i> siRNA within fibrotic lung lesions, effectively blocking fibrogenic signaling pathways and offering a clinically viable strategy for combating PF.