C57BL/6 mice were injected subcutaneously in the abdominal region with either blank PLGA MPs (BMP), the dMP, or the udMP (n = 4–5). (A) Injection site nodules were excised seven days later, enzymatically digested, and leukocytes analyzed by flow cytometry for CD86 and MHC-II expression on DCs recruited to the site of injection. (B) Frequency of surface marker expression (CD80, CD86, and MHC-II) was characterized on DCs to assess the capacity of the udMP to induce a suppressive phenotype. P-values (* = ≤ 0.05, ** = ≤ 0.01) were obtained by one-way ANOVA with Tukey’s significance test. Data is represented by mean ± SEM. Full gating scheme – see Supplemental Figure 8.