Effect of in vivo TNF treatment on short-term engraftment of human CD34⁺ CB cells in NOD-SCID mice.

Freshly isolated CD34⁺ CB cells were transplanted into irradiated NOD-SCID mice that subsequently received 3 injections of PBS (−TNF) or 5 μg TNF (+TNF) 24, 64, and 96 hours after transplantation. At 24 hours after the last injection (day 5) mice were killed, and BM analyzed for human (HuCD45/71) and murine (MuCD45.1) engraftment (as described in “Materials and methods”). Cells positive for HuCD45/71 were analyzed for percentage HuCD34⁺cells, which were sorted on a FACSVantage for subsequent studies in LTC-IC assay (Table 4). Lower panels show purity analysis of sorted cells. Results represent data from 1 of 2 experiments with similar results.