Fig. 6

In vivo therapeutic effects of human NK cells against orthotopic GBM xenograft tumors. a Experimental schedule illustrated. b Tumor volumes were determined and compared one week after the last NK cell injection (n = 7 for each group). I.T. = intratumoral transplantation, I.V. = intravenous injection. Data = mean + SE. *p < 0.05, ***p < 0.001, vs. control. c Apoptotic tumor cells in the xenograft tumors were analyzed by the TUNEL assay. TUNEL-positive cells were calculated and compared with the control group. Arrow = TUNEL positive cell, Data = mean + SE. ***p < 0.001, vs. control. d Human NK cells were traced by immunohistochemistry using a CD56-specific antibody (n = 3 for each group). Number of NK cells were calculated and compared with the control group. Arrow = CD56 positive cell, Data = mean + SE. ***p < 0.001, vs. control