Using immune tolerance breaking antibody platform, Transcenta generated a humanized IgG1 subtype anti-CD25 monoclonal antibody with reduced fucose (TST010). TST010 binds to human CD25 with high affinity and selectivity, but does not block IL-2 binding to CD25. Non-blocking activity to IL-2 signaling on human PBMC has been further confirmed by the phosphorylation of STAT5. By reducing fucosylation during cell culture process, TST010 mAb gains the enhanced ADCC activity in vitro and anti-tumor activity by depleting Treg cells and increasing CD8+T/Treg ratio in preclinical tumor models.