CD19 and leukemia: We found a significant reduction in leukemia engraftment in bone marrow aspirates of animals bearing REH cells and in the peripheral blood of NALM-6-bearing mice that were treated with CD19-TRAIL as compared to animals treated with CD19-IgG1, respectively (38.30% vs. 17.70%, p = 0.0476 and 43.5% vs. 24%, p = 0.0079, Supplementary Figure S3A,B).