“Bridging” therapy with 5-aza-cytidine supports NK-cell alloreactivity toward pediatric BCP-ALL in the early posttransplantation period. (A) Experimental setup. (B-C) Low-dose and long-term 5-aza-cytidine treatment does not exert statistically relevant BM cytotoxicity. Given is the number of human (B) or murine (C) CD45⁺ cells normalized to total live cells. Data depicted in Figure 6B were obtained in 5-aza-cytidine–treated huNSG mice, and data depicted in Figure 6C were obtained in 5-aza-cytidine–treated nonhumanized control mice. (D) Treatment with 5-aza-cytidine significantly reduces BCP-ALL tumor load in huNSG mice. (E) Low-dose 5-aza-cytidine treatment regimen does not exert relevant direct cytotoxic effects on pediatric BCP-ALL. Given is the number of vital blasts in the BM normalized to murine CD45⁺ cells in nonhumanized control NSG mice. (F) Calculated effect size of in vivo 5-aza-cytidine treatment on pediatric BCP-ALL burden. “Exp. I and II” denote the 2 different experiments in huNSG mice; “control I and II” denote the effect in the respective control groups. Data are representative of 2 independent experiments with a total of 11 huNSG mice and 14 control NSG mice. n.s., not significant.