Figure 3.
IL-12–producing cells are found in the spleens of mice injected systemically with STAg or LPS. Mice of the indicated strains were left untreated (A), or were intravenously injected with 0.5 μmol OVA (C), OVA + 40 μg LPS (D), or with 25 μg STAg (B, E–H). Animals were killed 6 h (B, E–H) or 4 h (C and D) after injection. Spleens were frozen, sectioned, and stained with anti–IL-12 p40 as detailed in Materials and Methods. Note “nests” of IL-12–producing cells after STAg or LPS injection. Arrows in C and D indicate the central arterioles. Original magnification: A, B, and E–H, ×100; C and D, ×200.