The benefit from NK cell may be attributed to its introduction of controllable GVHD together with an optimal degree of GVL effect, In a separate study, it was shown that serum IFN-γ increased along with the expansion of NKT-like cells in GVHD patients, and patients benefitted through treatment with basiliximab (anti-CD25 antibody) and etanercept (anti- IFN-γ antibody) [3]. Here, IFNG is linked to graft versus host disease.