Figure 3.

Increasing numbers of CD4⁺ and CD8⁺ T_RM cells form with recurrent contact hypersensitivity. The ear skin sections of a group of BALB/c mice at 35 days after the 1^st challenge (n = 6), re-challenge (n = 3), or re-re-challenge (n = 6) with 1% TNCB were analyzed by single immunohistochemistry staining with anti-CD3ε, CD4, or CD8α + CD8β mAbs. The numbers of positive cells along the cartilage are shown. Data for day 35 are the same as in Figure 2B. Bars represent means ± SE. *P < 0.05 between both ears on each day of the analysis (two-tailed paired t-test). The numbers inside and outside the bars indicate the fold change in each value [epidermis (red), dermis (blue), and total number (black)] relative to those in naïve ears on day 35.