The present disclosure is of an IgG2 anti-CD25 antibody that does not inhibit IL-2-CD25 interaction, is associated with enhanced binding to activated FcγR, and results in effective depletion of tumor-infiltrating Treg cells and improved control of colonized tumors. Regarding use. The antibody can be used in the treatment of cancer, such as solid tumors and hematological malignancies. [Selection diagram] None本開示は、IL-2-CD25相互作用を阻害せず、活性化FcγRへの結合の増強を伴い、腫瘍浸潤Treg細胞の効果的な枯渇及び定着腫瘍の制御の改善をもたらすIgG2抗CD25抗体の使用に関する。該抗体は癌の治療、例えば固形腫瘍及び血液癌の治療に使用することができる。【選択図】なし