Gene-modified HSPCs are capable of long-term, multilineage reconstitution of lethally irradiated recipients. (A) Experimental design. BM harvested from hCD46tg mice 8 weeks after in vivo transduction with HD-Ad–GFP and HD-Ad–SB was sorted for GFP⁺ cells. A total of 1 × 10⁶ GFP⁺ cells per recipient (pooled from different mice) were transplanted into lethally irradiated C57BL/6 mice. PBMCs were collected 4, 6, 8, 10, 12, and 14 weeks after transplantation, and analyzed for hCD46 and GFP expression by flow cytometry. N = 7. (B) Engraftment rate of transplanted cells based on hCD46 flow cytometry of PBMCs. Shown are single animals (filled squares) and the mean. (C) Percentage of GFP⁺ PBMCs analyzed at the indicated time points. (D) Week 16 GFP marking in BM lineage-depleted cells and cell fractions enriched for HSPCs (LSK, SLAM [LSK/CD150⁺/CD48⁻]). (E) Week 16 GFP marking in BM, PBMCs, and spleen lineage-committed cells (CD3, CD19, CD11b, and Gr-1). Shown are mean ± SD. One-way ANOVA with Bonferroni posttesting. (F) GFP expression in CD45⁺ cells of the lung and thymus. Shown are mean ± SD. n.s., not significant; SLAM, signaling lymphocyte activation molecules.