Clonal analysis of iBM-injected SRCs.

(A) The proportion of EGFP⁺ human cells was analyzed at 8 weeks after iBM transplantation. Samples were obtained from injected side tibia (i), noninjected side tibia (ii), and spleen (iii). Cells were stained with antihuman CD45 mAb and analyzed by flow cytometry. Representative FACS profiles are shown from 4 independent experiments. The relative frequencies of each population are indicated. (B) Southern blot analysis for lentivirus integration sites. Genomic DNA extracted from samples indicated earlier was digested with EcoRI, which recognizes a unique site in lentivirus vector, and was hybridized with an EGFP probe. Each band represents a unique lentiviral integration site, and it corresponds to each clone. Arrowheads indicate common integration sites. Representative Southern blot analysis of 2 independent experiments is shown.