Female SCID mice, nude mice and C57BL/6 mice of 4 weeks were used in animal experiments. All mice were maintained in the specific pathogen-free conditions and animal experiment procedures were approved by the Ethics Committee of Tianjin Medical University Cancer Institute and Hospital, in compliance with the principles and procedures of the NIH Guide for the Care and Use of Laboratory Animals. All groups were randomly divided. The CD25 antibody or the isotype control (0.5 mg per mouse, PC61, BioXcell, West Lebanon, NH, USA) was injected on days –2, 1 and 21 following the previous literature with modifications.18 (link) The CCL5 antibody or the isotype control (20 μg intratumorally per mouse, R&D Systems, Minneapolis, MN, USA) was injected twice a week. Harvested tumors were processed into the single-cell suspension with 1 mg/ml collagenase, 2.5 U/ml hyaluronidase and 0.1 mg/ml DNase. Details were shown in the Supplementary materials and methods.