Anti-Inflammatory Potential of Beclometasone-Loaded Filomicelles on Activated Human Monocytes

Polymeric micelles with a hydrophobic core represent versatile nanostructures for encapsulation and delivery of water-insoluble drugs. Here, water-insoluble beclometasone dipropionate (BDP) which is a potent anti-inflammatory therapeutic agent but limited to topical applications so far, is encapsulated. Therefore, this work used an amphiphilic block copolymer self-assembling into flexible polymeric filomicelles, which have recently proven to selectively target inflamed areas in patients with inflammatory bowel disease (IBD). The small diameter and flexibility of these filomicelles is considered beneficial for transepithelial passages, while their length minimizes the unspecific uptake into nontargeted cells. This work successfully establishes a protocol to load the water-insoluble BDP into the core of the filomicelles, while maintaining the particle stability to prevent any premature drug release. The anti-inflammatory efficacy of BDP-loaded filomicelles is further investigated on lipopolysaccharide (LPS) stimulated human monocytes. In these ex vivo assays, the BDP-loaded filomicelles significantly reduce TNF-α, IL-6, IL-1ß, IL-12p70, IL-17a, and IL-23 release after 24 h. Additional time course study of drug-loaded filomicelles and their comparison with a common water-soluble and unspecific corticosteroid demonstrate promising results with significant immune response suppression in stimulated monocytes after 2 and 6 h. These findings demonstrate the potential of polymeric filomicelles as a vehicle for potent water-insoluble corticosteroids.