DNFB induces strong tissue necrosis in TNFR1^+/+ mice. (A) DNFB-sensitized and -challenged TNFR1^+/+ mice developed reduced ear swelling responses 24 hours after ear challenge compared with TNFR1^−/− mice (n = 5-7). (B) TNCB-sensitized and -challenged TNFR1^−/− mice developed reduced ear swelling responses 24 hours after ear challenge compared with TNFR1^+/+ mice (n = 16-27). (C) Enhanced tissue necrosis in TNFR1^+/+ mice after DNFB application. Hematoxylin and eosin–stained abdominal skin sections from TNCB-treated (top left) or DNFB-treated (top right) TNFR1^+/+ and from TNCB-treated (bottom left) or DNFB-treated (bottom right) TNFR1^−/− mice at day 5 after hapten application on the abdomen (n = 3-5).