Detection of normal and leukemic human cells in the BM of engrafted mice. Southern analysis of DNA extracted from the BM of NOD/SCID mice transplanted with 108 PB cells from patient 6 and assessed 3 to 6 weeks later. Each numbered lane contains the DNA from a separate mouse. The DNA was digested with Bgl II and then probed using a Bgl II/HindIII fragment containingBCR exon 131 to detect germline and rearrangedBCR genes. (M) Indicates the molecular weight marker. (P) Indicates DNA extracted from the PB of the patient. The level of human cell engraftment in the BM of each mouse was determined separately by Southern blot analysis using a human-specific probe as described in Fig1A. The percentage of BCR+ cells was determined as described in Materials and Methods. (ND), not detected.
