Figure 7.

CD11b⁺ DCs from Rag2^+/+ but not from Rag2^−/− mice express CD8α, up-regulate CD205, and down-regulate CD4 molecules after PPV-VLPs injection. (A) C57BL/6 Rag2^+/+ or Rag2^−/− mice were intravenously injected with 50 μg PPV-VLPs. Noninjected mice from each strain were used as a control. 15 h later, CD11c⁺ spleen cells were purified and stained with anti-CD11b and anti-CD8α antibodies plus one of the following antibodies: anti-CD11c, anti-CD4, anti-CD205, anti-CD8β, or anti-CD86. Cells were analyzed on a FACScalibur^® cytometer. One representative experiment out of two (for Rag2^+/+) or three (for Rag2^−/−) is depicted. (B) Expression of CD8α mRNA by DC subsets. Mice were injected with PPV-VLPs and 90 min later, CD8α⁻ CD11c⁺ spleen cells were purified and cultured for 15 h (Exp. 1) or for different times (0, 3, 5, 8, and 15 h, Exp. 2). Then, the mRNA was extracted for RT-PCR (two rounds of 40 cycles per round) using primers for CD8α. mRNA from CD8α⁺ DCs purified 90 min after injection was used as a positive control.