Numbers of peripheral blood NK cells in patients undergoing transplantation with autologous PBSC. Mean number of NK cells/μL (CD16/CD56⁺) in the peripheral blood of eight patients transplanted with FACS-sorted CD34⁺ HPC is shown as open circles (○). Number of NK cells/μL in the blood of 11 patients receiving unmanipulated PBSC autografts are shown in the open triangle (▵).