Remote Co-loading of amphipathic acid drugs in neutrophil nanovesicles infilled with cholesterol mitigates lung bacterial infection and inflammation.

Lung bacterial infections could result in acute lung inflammation/injury (ALI) that propagates to its severe form, acute respiratory distress syndrome (ADRS) leading to the death. The molecular mechanism of ALI is associated with bacterial invasion and the host inflammation response. Here, we proposed a novel strategy to specifically target both bacteria and inflammatory pathways by co-loading of antibiotics (azlocillin, AZ) and anti-inflammatory agents (methylprednisolone sodium, MPS) in neutrophil nanovesicles. We found that cholesterol infilling in the membrane of nanovesicles can maintain a pH gradient between intra-vesicles and outer-vesicles, so we remotely loaded both AZ and MPS in single nanovesicles. The results showed that loading efficiency of both drugs can achieve more than 30% (w/w), and delivery of both drugs using nanovesicles accelerated bacterial clearance and resolved inflammation responses, thus preventing the potential lung damage due to infections. Our studies show that remote loading of multiple drugs in neutrophil nanovesicles which specifically target the infectious lung could be translational to treat ARDS.