Extended duration of IL-7 treatment during the clonal contraction phase alters phenotypic attributes of LCMV-specific CD8 T cells. Mice were infected with LCMV-Clone 13 and treated with either IL-7 or PBS between days 8 and 30 PI, as described in Figure 3. At day 31 PI, splenocytes were stained with anti-CD8, anti-CD44, and D^b/GP33 tetramers in combination with antibodies against KLRG-1, CD127, CD122, CD43, PD-1, and LAG-3 (A-C). Splenocytes were stained with anti-CD8, D^b/GP33 tetramers, and antibodies against intracellular Bcl-2, Cbl-b, and Ki-67 molecules (D). Data were analyzed by flow cytometry, and the FACS plots are gated on tetramer-binding CD8 T cells. The numbers in panels A, C, and D are the mean fluorescence intensity (MFI) and/or percentages among tetramer-binding CD8 T cells. Data are from analysis of 4-5 IL-7–treated (black line) or PBS-treated (gray line) mice and are representative of 2 experiments. Stainings with anti–Cbl-b antibodies after incubation with the specific immunogenic Cbl-b peptide are shown as dotted lines. *P ≤ .05; **P ≤ .005; ***P ≤ .001.