Inhalable FN-binding liposomes or liposome-exosome hybrid bionic vesicles encapsulated microparticles for enhanced pulmonary fibrosis therapy.

Pulmonary fibrosis (PF) is a chronic, progressive and irreversible interstitial lung disease that seriously threatens human life and health. Our previous study demonstrated the unique superiority of traditional Chinese medicine cryptotanshinone (CTS) combined with sustained pulmonary drug delivery for treating PF. In this study, we aimed to enhance the selectivity, targeting efficiency and sustained-release capability based on this delivery system. To this end, we developed and evaluated CTS-loaded modified liposomes-chitosan (CS) microspheres SM(CT-lipo) and liposome-exosome hybrid bionic vesicles-CS microspheres SM(LE). The prepared nano-in-micro particles system integrates the advantages of the carriers and complements each other. SM(CT-lipo) and SM(LE) achieved lung myofibroblast-specific targeting through CREKA peptide binding specifically to fibronectin (FN) and the homing effect of exosomes on parent cells, respectively, facilitating efficient delivery of anti-fibrosis drugs to lung lesions. Furthermore, compared with daily administration of conventional microspheres SM(NC) and positive control drug pirfenidone (PFD), inhaled administration of SM(CT-lipo) and SM(LE) every two days still attained similar efficacy, exhibiting excellent sustained drug release ability. In summary, our findings suggest that the developed SM(CT-lipo) and SM(LE) delivery strategies could achieve more accurate, efficient and safe therapy, providing novel insights into the treatment of chronic PF.