Percentage eGFP-expressing cells in peripheral donor-derived T cells of HSC/HPC and T cell (TC)-transplanted animals. Six weeks after transplantation, blood was drawn from HSC/HPC and TC recipient mice. Percentages of eGFP-positive cells in the CD45.1⁺ (donor cells) and CD3⁺ (T cell) gates of animals that received transplants of HSCs/HPCs (■) and TCs (□). Engraftment of transferred gene-modified T cells was at least equal, if not higher, compared with HSCs/HPCs. Error bars represent SD.