Figure 5.

CD8α ALN-1 enhances the efficacy of adoptive T cell transfer by endorsing effector CD8⁺ T cell generation in both tumor-draining lymph node and tumor microenvironment. (A) Mice carrying established LLC-OVA tumors received OT-I CD8⁺ T cells and treatment with PBS or CD8α ALN-1 (10 µg). Controls did not receive OT-I CD8⁺ T cells and were treated with OVA alone (100 µg) or combined with CD8α ALN-1 (10 µg). (B) LLC-OVA tumor growth. Lines represent individual mice. Shown is a representative of two independent experiments with n=5 mice/group. Kaplan-Meier curves demonstrate time to reach tumor volumes exceeding 200 mm³. Pooled data from two independent experiments with n=10 mice/group combined. (C, D) Frequencies of OT-I CD8⁺ T cells within total CD8⁺ T cells, naive and effector phenotypes within OT-I CD8⁺ T cells and T-bet expression within the total and effector OT-I CD8⁺ T cell population in the TDLN (C) and tumor tissue (D) with representative flow cytometry dot plots. (E) Frequencies of OT-I CD8⁺ T cells within the total CD8⁺ T cell population and production of IFN-γ and TNF by OT-I CD8⁺ T cells following ex vivo splenocyte restimulation with representative flow cytometry dot plots. Bars represent the mean ± SEM of an experiment with n=6 mice/group (for TDLN and spleen samples) or n=3 mice/group (for tumor samples, as two mice were pooled together). *p<0.05, **p<0.01, ****p<0.0001; ns, p≥0.05 by log-rank (Mantel-Cox) testing (B) or by unpaired Student’s t-test (C–E). See also online supplemental figure 8 and 9. IFN-γ, interferon-γ; LLC, Lewis lung carcinoma; ns, not significant; OVA, ovalbumin; TDLN, tumor-draining lymph node; TNF, tumor necrosis factor.