Development of PSL-Loaded PLGA Nanoparticles for the Treatment of Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) can easily develop once sensitization is established by exposure to small amounts of antigen, and steroids are used for treatment. In this study, we evaluated the therapeutic efficacy of prednisolone (PSL)-loaded poly(DL-lactide-co-glycolide) (PLGA) nanoparticles (NPs) on a mouse model of contact dermatitis (CHS). Nanoparticles were prepared using a poor solvent diffusion method, and particle size distribution and mean particle size were measured using dynamic light scattering. Treatment experiments with PSL-loaded PLGA NPs were performed before and after sensitization with 1-fluoro-2,4-dinitrobenzene (DNFB), and evaluation was performed by quantifying intracutaneous IL-4 and TNF-α levels in a mouse model of CHS using ELISA. When PSL-loaded PLGA NPs were administered before sensitization, IL-4 expression was significantly decreased, and TNF-α tended to decrease in the group treated with PSL-loaded PLGA NPs compared to the non-treated group. When PSL-loaded PLGA NPs were administered after sensitization, IL-4 expression was significantly decreased in the group treated with PSL-loaded PLGA NPs compared to the non-treated group. In both cases, there were no significant differences between the PSL-loaded PLGA NP treatment group and the PSL-containing ointment group. These results suggest that, in the treatment of CHS, PSL-loaded PLGA NPs show a certain therapeutic effect when preadministration.