Thus, we tested the effects of ICIs targeting CTLA-4 and PD-L1 on these cells, and we found that the combination of novel PD-L1_1 and ID-1 mAbs, previously generated in our laboratory, leads to an enhanced activation and anti-tumor activity of NK cells in co-cultures with breast cancer cell lines, with respect to the clinically validated atezolizumab and ipilimumab that, on the other hand, activate Pan T cells more efficiently. Here, CTLA4 is linked to breast cancer.