Analyses of human CD45⁺ (hCD45⁺) cells in the BM and PB of NOD/SCID mice that had received transplants.

NOD/SCID mice received irradiated accessory cells, precocultured CD34⁺ cells, or CD34⁺ cells that had been expanded on hTERT-stromal cells or primary stromal cells. Mice were killed 6 weeks after transplantation, and the BM (panel A) and PB (panel C) were analyzed by flow cytometry. In Panels A and C, × indicates accessory cells; ■, precocultured CD34⁺cells; ▵ CD34⁺ cells that had been expanded ex vivo in the absence of stromal cells for 2 weeks; ○, CD34⁺ cells that had been expanded on primary stromal cells for 2 or 4 weeks; ●, CD34⁺ cells that had been expanded on hTERT-stromal cells for 2 or 4 weeks. The dotted lines indicate cutoff level (0.1%) of successful engraftment of human hematopoietic cells. *P < .05 versus precocultured CD34⁺ cells (Mann-Whitney U test). (B) PCR amplification of human ALU sequences and hCD45 percentages of the BM of NOD/SCID mice. Lanes 1-3, mice (n = 3) receiving transplants of accessory cells only; lanes 4-8, mice (n = 5) receiving transplants of precocultured CD34⁺ cells. Lane 9, PC indicates positive control (human PB MNCs); lane 10, NC indicates negative control mouse (n = 1) without transplants. hCD45% indicates the percentage of the human CD45⁺ hematopoietic cells in the BM of mice that had received transplants. (D) Representative data of flow cytometric analysis of the PB MNCs of NOD/SCID mice, using antihuman CD45 antibody. NOD/SCID mice received transplants of either precocultured CD34⁺ cells (upper right), hematopoietic cells that had been expanded on primary stromal cells (lower left), or hTERT-stromal cells (lower right) for 4 weeks. Representative data with an isotype-matched antibody for the PB MNCs of mice that had received transplants were also shown (isotype control, upper left); y-axis shows the staining of propidium iodide (PI).