CTLA4 and neoplasm: The significant reduction in Tregs seen here after treatment of 9464D-GD2 with RT combined with 1⁄2 dose IT-IC, anti-CTLA-4, CpG, and anti-CD40 was also seen after treatment of B78 melanoma with IT-IC, anti-CTLA-4, CpG, and anti-CD40 without radiation [12], suggesting that this immunotherapy plays a significant role in reducing Tregs in the tumor microenvironment.