Fig. 3

Cytokine response in each stimulator. Two and four weeks after booster vaccination, stimulation was carried out by three stimulators with heat-killed B. pertussis (hBp), PT, FHA, and PRN antigens or the mixture of the two (hBp + antigen) for 3 days (n = 5). The culture medium was used as a negative control, and 1 µg/mL PWM was used as a positive control. The results were obtained via commercially available cytokine ELISA kits and presented as the mean ± SEM (pg/mL). All results were baseline (medium only) corrected. Statistical differences were tested with 2-way ANOVA and Tukey’s multiple comparison test. A IFN-γ, IL-17A, and IL-5 cytokine levels were assessed for each stimulator. There were no statistically significant differences between the three vaccinated groups; however, different cytokines revealed various response levels according to the stimulator type. B The mean cytokine secretions of the three vaccinated groups, positive control group and two study groups had different levels by what stimulators used. When the mean cytokine levels were subtracted by the cytokine levels of the negative control group (saline injected) to correct baseline, Th1 (IFN-γ) immunity was confirmed by stimulator hBp. Th1 (IFN-γ) / Th2 (IL-5) polarization was confirmed by stimulator hBp + antigen and antigen respectively. (SEM = standard errors of the means, PT = pertussis toxin, FHA = filamentous haemagglutinin, PRN = pertactin) (*p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001)