FIGURE 4.

Activation of IL-17- and IFN-γ-producing CD8 T cells in the hapten challenge site requires ICAM-1. A. Groups of 4 C57BL/6 mice and B6.ICAM-1^−/− mice were sensitized with 0.25% DNFB on days 0 and +1. On day +5, the indicated groups of sensitized and non-sensitized naïve mice were challenged with 0.2% DNFB. In addition, wild-type C57BL/6 mice were sensitized with DNFB and on day +4, lymph node cell suspensions were prepared and aliquots of 4 × 10⁶ T cells were injected i.v. into naïve wild-type or ICAM-1^−/− mice immediately prior to challenge with 0.2% DNFB. Challenged skin was excised 6 h after challenge, whole cell RNA was prepared and was used to assess mRNA expression of IL-17, IFN-γ, and CXCL1/KC in the skin samples by quantitative RT/PCR. The mean expression level for each of 4 samples per group ± SEM is shown. B. Total protein was prepared from excised skin samples of each individual in the groups and tested for levels of CXCL1 by ELISA. The mean concentration ± SEM for 4 individual samples per group is shown. All results are representative of two individual experiments each. *p ≤ 0.05.