Aerosolized ApoA1 Nanoparticles Synthesized by Microfluidics Cross the Lung Barrier and Modulate Inflammation

High-density lipoproteins exert vasculoprotective effects, mainly through apolipoprotein A1, which has led to the development of treatments based on apolipoprotein A1 nanoparticles (A1NPs) administered intravenously, mainly for the treatment of cardiovascular diseases. However, their potential as therapy for lung pathologies has not yet been explored. In this work, we produced A1NPs using microfluidics and characterized their therapeutic potential for lung delivery. Their morphology was characterized by dynamic light scattering and transmission electron microscopy. A1NPs toxicity and cellular uptake were performed on both endothelial (HMEC-1) and epithelial (A549) cells and their anti-inflammatory activity was evaluated on TNF-α-stimulated HMEC-1. A1NPs biodistribution was explored in lung mice after aerosolization and their transcytosis was further investigated using A549 air-liquid interface model. Our results demonstrate that the microfluidic synthesis of A1NPs was reproducible and yielded discoidal particles with sizes ranging from 7-12 nm. A1NPs were internalized by both cells without being cytotoxic and significantly reduced IL-6 expression. Aerosolization resulted in homogeneous distribution in lungs, without causing an immunogenic response. A fraction of A1NPs crossed alveolar epithelial cells both in vitro and in vivo, paving the way for future therapeutic strategies targeting not only the lungs, but also other peripheral organs. These results are promising for the use of A1NPs as vectors for therapeutic molecules, which could exert synergistic protective effects with Apolipoprotein A1. This is the first study to show the non-invasive administration of A1NPs by aerosolization, which may improve their bioavailability in lungs and appears to be a promising approach for treating lung diseases.