Pressure-sensitive multivesicular liposomes as a smart drug-delivery system for high-altitude pulmonary edema.

Changes in bodily fluid pressures, such as pulmonary artery pressure, play key roles in high-altitude pulmonary edema (HAPE) and other disorders. Smart delivery systems releasing a drug in response to these pressures might facilitate early medical interventions. However, pressure-responsive delivery systems are unavailable.

Dry Powder Formulations for Inhalation Require a Smaller Aerodynamic Diameter for Usage at High Altitude.

Background: High Altitude Pulmonary Edema (HAPE) seriously threatens the health of people at high altitudes. There are drug treatments for HAPE, and dry powder formulations (DPFs) represent a rapid and accessible delivery vehicle for these drugs. However, there are presently no reports on the inhalability of DPFs in low-pressure environments.

Re-exposure of chitosan by an inhalable microsphere providing the re-education of TAMs for lung cancer treatment with assistant from sustained HS generation.

The re-education of tumor-associated macrophages (TAMs) is an effective strategy to inhibit the growth and metastasis of lung cancer. We have reported that chitosan could re-educate the TAMs and then inhibit cancer metastasis; however, the re-exposure of chitosan from the chemical corona on their surface is critical for this effect. In this study, a strategy was proposed to re-expose the chitosan from chemical corona, and a sustained HS generation was applied to enhance the immunotherapy of chitosan.

O-carboxymethyl chitosan based pH/hypoxia-responsive micelles relieve hypoxia and induce ROS in tumor microenvironment.

The hypoxia in tumor microenvironment (TME) can upregulate the HIF-1α and PD-L1 expression and cause immunosuppression of tumor. In this study, a carboxymethyl chitosan-based pH/hypoxia-responsive and γ-FeO/isosorbide dinitrate carrying micelle was designed, and it could catalyze endogenous HO to generate oxygen and relieve hypoxia in TME, so as to relieve the overexpression of HIF-1α and PD-L1 in tumor; meanwhile, it could react with HO to release ROS via Fenton reaction and induce cytotoxicity in tumor. Along with these multiple effects, this carboxymethyl chitosan-based micelles could provide a comprehensive strategy for tumor treatment.