To test if LTβR signaling in MSCs impacts ALL growth, non-malignant hematopoiesis, and mouse survival, we transplanted ALL cells into mice conditionally deficient in Ltbr in MSCs (Ltbrfl/fl; LeprCre/+ mice, from here on referred as LTβR∆) that also report Il7 transcription via GFP expression (Il7GFP/+). Here, IL7 is linked to acute lymphoblastic leukemia.