CTLA4 and neoplasm: Some novel immunotherapies target two or more markers on tumor-infiltrating Tregs, such as CTLA4/OX40 or CTLA4/PD-1, which improves specificity and reduces off-target effects, or adjusting the affinity of the antibodies so that they bind weakly to low-density targets and strongly to high-density targets, another method is to adjust the dosage to avoid excessive killing of Teffs.