FIG 2.

Long-term immunity to T. cruzi by TSKB-peptide Tg mice. (A) TSKB20/K^b+ or TSKB18/K^b+ CD8⁺ T cells were measured longitudinally in peripheral blood of naive or T. cruzi-infected WT, TSKB20 Tg, TSKB18 Tg, or TSKB20/18 Tg mice as described foe Fig. 1B. (B) CD44^hi KLRG-1⁺ CD8⁺ T cells detected in blood of naive or T. cruzi-infected TSKB20/18 Tg and WT littermates at 21 days postinfection. Histograms are gated on CD8⁺ CD4⁻ lymphocytes, and numbers indicate the proportions of cells within gates. (C) CD44^hi KLRG-1⁺ CD8⁺ T cells measured longitudinally in blood of mice analyzed as in panel B. (D) CD127 staining on peripheral blood CD44^hi-gated CD8⁺ T cells (black line) compared with CD127 staining on total CD8⁺ T cells from a naive individual (dashed line). Filled gray histograms are CD44^hi-gated CD8⁺ T cells not stained for CD127. Numbers indicate the proportions of CD44^hi-gated CD8⁺ T gated cells expressing low (left) or high (right) levels of CD127 at 220 days postinfection. Data in panels B and D are representative of 2 identical experiments (n = 4 to 8 per infected group). (E) Proportion of CD44^hi-gated CD8⁺ T cells stained positive for CD127 measured longitudinally in blood of mice analyzed as in panel D. Data in panels A, C, and E are means ± standard deviations (SD) (n = 3 to 11 per infected group) from one experiment (black squares are WT, up triangles are TSKB20 Tg, down triangles are TSKB18 Tg, diamonds are TSKB20/18 Tg, and circles are uninfected naive mice) and are representative of two similar longitudinal experiments.