TNFSF13B and B-cell chronic lymphocytic leukemia: Additionally, it has been reported that activated NK cells release soluble B cell activating factor (BAFF) which enhances the metabolic activity of CLL cells and reduces their susceptibility to direct NK cell cytotoxicity and ADCC induced by anti-CD20 therapeutic mAbs, effects which are prevented by the BAFF neutralizing mAb belimumab [210].