A total of 2.5 × 106/ml peripheral blood mononuclear cells were cultured with 2.5 × 106/ml live P. acnes in the exponential phase for (a) IFN-γ or the stationary phase for (b) IL-17 and (c) IL-10. ELISA was conducted on the supernatant to determine the concentration of IFN-γ, IL-17, and IL-10. Data are from one of five similar experiments. Statistics show t-test comparisons with the maximum two-way P value between the phylotype groups indicated. *P < 0.05, **P < 0.01, ***P < 0.001. p±, presence or absence of a large plasmid; RT, ribotype.