Fig. 6. MCA boosts adaptive immunity and controls reinfection.

(A) Weight of PNs and total number of cells in the PN 24 hours after footpad injection of WT mice with saline, 10 μg of mastoparan, or mastoparan 17, or MC-depleted mice with mastoparan (Cre⁺ mastoparan group). (B) Numbers of CD11c⁺ IA/IE⁺ antigen-presenting cells, LCs, and CD103⁺ DCs in PNs 24 hours after various treatments described above. Data are representative of two independent experiments. (C) Schematic showing experimental plan and graph depicting IgG geometric mean titer (GMT) against whole S. aureus cells in sera collected on day 21 after infection from mice infected with S. aureus and treated with vehicle, mastoparan, or mastoparan 17 for 2 weeks or in sera of uninfected (naïve) mice (n = 5). (D) Lesion size 24 hours after reinfection with 10⁸ S. aureus of mouse groups described above (n = 5). Note that the lesion sizes were larger since the bacteria were not coated with microbeads (see Materials and Methods). Data were analyzed via unpaired two-tailed Student’s t test or ANOVA. Error bars represent SEM. *P < 0.05, **P < 0.01, ***P < 0.001. ELISA, enzyme-linked immunosorbent assay.