C57bl 6 mice

C57BL/6 mice and Rosa26Cre-ERT2 mice were purchased from the Jackson Laboratory. The dLck-Cre TGFβRII^flox/flox (KO) mice, generously given by N. Zhang (University of Texas at San Antonio, San Antonio, TX), were crossed to LCMV D^bGP33-specific TCR transgenic P14 mice in-house. To induce persistent LCMV infection, 6–8-wk-old female C57BL/6 mice were given anti-CD4–depleting antibody GK1.5 (Bio X Cell) i.p. twice before i.v. infection with 2 × 10⁶ PFU LCMV clone 13 strain (Matloubian et al., 1994 (link)). All animal experiments were performed in accordance with the Emory University Institutional Animal Care and Use Committee.

Female C57BL/6J mice (aged 6–8 weeks) were purchased from SPF Biotechnology Co., Ltd. (Beijing, China). For the tumor anti-PD-1 antibody treatment models, mice were subcutaneously implanted with 1 × 10⁶ B16 or LLC cells in the right flank on day 0. A total of 200 μg anti-PD-1 (BioXcell, clone 29 F.1A12) was administered by intraperitoneal injection every 2 days for a total of three times on D7 or D14 after tumor inoculation. Tumor growth was measured, and survival was observed. For the models of the combination of anti-PD-1 antibody and IL-2 treatment, mice were subcutaneously implanted with 1 × 10⁶ B16 cells into the right flank day 0. B16-bearing C57BL/6 mice were left untreated or treated with 200 μg anti-PD-1 (BioXcell, clone 29 F.1A12), IL-2 (1 × 10⁴ U per mouse) therapy, or combination therapy every 2 days for a total of three times, starting from D7 or D14. For OT1⁺ CD8⁺ T-cells adoptive transfusion therapy, mice were subcutaneously implanted with 1 × 10⁶ B16 cells into the right flank on day 0. PBS, OT1⁺ CD8⁺ T cells overexpression vector, ITGAL, STAT5A, and STAT5B (1 × 10⁶ cells per mouse) were administered via tail vein injection on D7. Tumor growth was measured every second or third day, and tumor volume was calculated as (length×width×width)/2. All animal experiments were approved by the Animal Care and Use Committee of Zhengzhou University.