DTH responses in WT and TPCR transgenic mice. (A) Mice were directly challenged with the antigen (DNFB) in the right pinna and accumulation of infiltrating ¹²⁵I-UdR–labeled mononuclear cells into both ears (R/L ratio) was estimated 26 hours latter. The results shown represent 2 different experiments; 5 mice were tested per group. Error bars represent the standard deviation of replicates. *P < .005. (B) Histologic sections of the right pinna of Tg8.7 and WT mice. Pinnae were fixed in buffered formalin, cut, and stained with hematoxylin and eosin. Note subepidermal and epidermal infiltration of inflammatory cells, mainly neutrophils, as well as lymphoid and plasma cells in the transgenic pinnae (arrows).