FIGURE 6.

SB203580 enhances CpG effects to induce a Th1 response. A, BMMφs or (B) BMDCs derived from C57BL/6 mice were treated without or with increasing doses of SB203580 for 1 h and then infected without or with L. major parasites at MOIs of 0 (◯), 2:1 (엯), or 5:1 (■) in the absence or presence of CpG for 16 h. Supernatants were harvested and subjected to ELISA to detect IL-12p40 (A) and IL-12p70 (B) production. C and D, BMMφs derived from C57BL/6 mice were primed with IFN-γ (100 U/ml) for 2 h and then infected without (C) or with L. major parasites at MOIs of 5:1 in the presence of SB203580 at increasing dosages for 1 h. The cells were then stimulated with LPS for 24 h and the supernatants were collected. Equal volumes of supernatants were mixed with Griess reagent for 10 min, and NO₂^– accumulation was measured. E and F, C57BL/6 mice were injected in the hind footpad with a 25-μl mixture containing HKLM (25 μg) and CpG (0.5 μg) plus SB203580 (20 μM) (◯) or the inactive SB202474 (엯). This was repeated 7 d later. On day 10, mice received an injection of HKLM (50μg) i.p. A periorbital blood sample (~0.2 ml) was taken from each mouse at the indicated time intervals and an ELISA was performed to detect IL-12p40 (E) and IFN-γ (F). Values represent the mean ± SD (n = 4 mice/group). G, C57BL/6 mice were injected in the hind footpad with two shots (day 0 and day 10, n = 4) or one shot (day 7, n = 4) of HKLM (25 μg) and CpG (0.5 mg) plus SB203580 (20 μM) (◯) or inactive SB202474 (엯). On day 17, splenocytes from naive or injected mice were harvested and incubated with or without HKLM for 72 h. Supernatants were collected and IFN-γ was measured by ELISA. Values represent the mean ± SD (n = 4 mice/group). The p values were determined by a Student t test. *p < 0.05.