Sequential co-infusions on days +7, +21, +35 of CTLA4-Ig and DLI in PTCy-based haplo-HCT was shown to be associated with significant surges of NK cells, a low incidence of GVHD and NRM, and failure to proliferate NK cells was associated with subsequent disease progression (115). The gene discussed is CTLA4; the disease is graft versus host disease.