Encapsulation of imiquimod in Ac-DEX microparticles increases macrophage activation in vitro. (A) 5×106/mL RAW 264.7 and MH-S macrophages (N=3) were stimulated for 6 hours with medium, free imiquimod, encapsulated imiquimod, or empty particles, and prepared individually for real-time PCR analysis for iNOS and PD1-L1 expression. Gene expression (mean ± SEM) is expressed as the fold increase over medium controls after normalization to hypoxanthine guanine phosphoribosyl transferase HPRT. (B) 1×106/mL RAW 264.7 and MH-S (N=3) were stimulated with medium, free imiquimod, encapsulated imiquimod, or empty particles. After 24 hours, the supernatants were removed and the presence of nitrite was quantified by the Griess assay. Graphs are representative of at least two individual experiments. *=p value <0.05, **=p value <0.01, ***=p value <0.001