For this purpose, surface molecules expressed at much higher levels on Tregs than T cells are used as targets, such as CD25, CTLA-4, GITR, 4-1BB, OX-40, LAG3, TIGIT, CCR4, and CCR8; tumor burden control has also been observed (58, 100, 104, 105). The gene discussed is CTLA4; the disease is neoplasm.