FIG. 2.

p38 MAP kinase regulates the production of IFN-γ by B. burgdorferi-specific effector Th1 cells. (A) CD4⁺ T cells were purified from mice infected with B. burgdorferi for 2 weeks and treated with either SB203580 or vehicle (1.3% dimethyl sulfoxide in phosphate-buffered saline) (Control) during infection. The cells were restimulated in the presence of a B. burgdorferi lysate (10 μg/ml) in the presence of mitomycin C-treated APCs. IFN-γ was quantified by capture ELISA 40 h after the initial stimulation. (B) Purified CD4⁺ T cells from infected C3H mice were stimulated with B. burgdorferi (Bb) in the absence or presence of 5 μM SB203580. IFN-γ was quantified 40 h later in the supernatants by ELISA. The data are representative of the results of three to five independent experiments. The asterisk indicates that the P value is <0.001, as determined by Student's t test.