DNFB-induced CHS model

The left ears of mice were sensitized epicutaneously with 0.25% DNFB for 2 consecutive days; 5 days later, the right ear was challenged with 0.25% DNFB. At 0–120 hours after challenge, the ear thickness was measured. In order to evaluate only the sensitization process, at 5 days after sensitization the left ear-draining lymph nodes (dLNs) and spleen were collected and the sensitized T and NK cells were analyzed. In some cases, mice were euthanized at 48 hours after challenge and their right ears were harvested for analysis. For transfer experiments, CD45.1⁺ naïve C57BL/6 mice were sensitized with 0.25% DNFB on both ears for 2 days; 5 days later, 2 x 10⁷ sensitized leukocytes isolated from dLNs were intravenously (i.v.) transferred to CD45.2⁺ recipient chimeric mice; 1 day later, these recipients were treated with DNFB on both ears. After an additional 48 hours, the ears were collected and analyzed.