Theranostic nanoemulsions for macrophage COX-2 inhibition in a murine inflammation model

• Inhibition of COX-2 in macrophages as novel strategy to treat inflammation.
• Theranostic nanoemulsion facilitated celecoxib delivery to macrophages in vitro and in vivo.
• Macrophage infiltration reduced at the inflamed site with celecoxib-nanoemulsion delivered to macrophages.
• Achieved therapeutic response (macrophage infiltration) monitoring with a single dose of a theranostic nanoemulsion.

Targeting macrophages for therapeutic and diagnostic purposes is an attractive approach applicable to multiple diseases. Here, we present a theranostic nanoemulsion platform for simultaneous delivery of an anti-inflammatory drug (celecoxib) to macrophages and monitoring of macrophage migration patterns by optical imaging, as measurement of changes in inflammation. The anti-inflammatory effect of the theranostic nanoemulsions was evaluated in a mouse inflammation model induced with complete Freund's adjuvant (CFA). Nanoemulsions showed greater accumulation in the inflamed vs. control paw, with histology confirming their specific localization in CD68 positive macrophages expressing cyclooxygenase-2 (COX-2) compared to neutrophils. With a single dose administration of the celecoxib-loaded theranostic, we observed a reduction in fluorescence in the paw with time, corresponding to a reduction in macrophage infiltration. Our data strongly suggest that delivery of select agents to infiltrating macrophages can potentially lead to new treatments of inflammatory diseases where macrophage behavior changes are monitored in vivo.

Figure optionsDownload high-quality image (182 K)Download as PowerPoint slide