RNA was extracted from infected and healthy skin for RT-PCR (n = 4 mice per group). (a) Heatmap of mRNA expression of cytokines and chemokines in Staphylococcus aureus SSTI at 3 h, 6 h, and 24 h after infection in mice receiving naive (−) or protective (+) sera. Gene expression was quantified as fold changes relative to healthy uninfected skin. (b) Representative cytokines and chemokines. The Benjamini–Hochberg procedure was performed for multiple comparisons using the false discovery rate correction with a q-value < 0.05. Data are presented as mean ± SEM. *P < 0.05. h, hour; NS, not significant; SSTI, skin and soft tissue infection.