Figure 4. Loss of PD-L1 or Mutation of the PD-L1 Cytoplasmic Domain Impairs T Cell Responses to an Infection Dependent on DC Migration.

(A) Representative flow plots and numbers of ova-specific T cells identified as B220−CD3+CD8+ T cells with a K^b SIINFEKL-specific tetramer (NIH tetramer Core Facility) following subunit immunization in WT, Pdl1^−/−, and Pdl1^CyMt mice. Mice were immunized with ova (10 μg/injection), poly(I:C) (5 μg/injection), and αCD40 (5 μg/injection) in the flanks and hind footpads. Data are shown from the popliteal and inguinal LNs 7 days post infection (dpi). In the data shown, n = 3 mice per group. The experiment was repeated two times with similar results.

(B) Representative flow plots and numbers of ova-specific T cells, as in (A), following subcutaneous infection with LM-ova. Mice were infected with 1e3 CFU in the hind footpads. Data are shown are from the popliteal LNs 7 dpi. n = 5–6 mice per group. The data shown are combined from two independent experiments.

(C) Representative flow plots and numbers of ova-specific T cells, as in (A) and (B), following intravenous infection with LM-ova. Mice were infected with 2e3 CFU via tail vein injection. Data are shown from the spleens 7 dpi. n = 5–8 mice per group. The data shown are combined from two independent experiments. Statistical analysis was done using a one-way ANOVA. *p < 0.05; **p < 0.01; n.s., p > 0.05. Error bars indicate standard error of the mean. See also Figure S5.