Study design. (A) Autologous peripheral blood stem cell transplantation (PBSCT). Cytokine-mobilized CD34⁺ cells were collected by apheresis from 2 animals, 96E019 and 96E025. Harvested cells were transduced with neomycin phosphotransferase retrovirus vectors (LNL6 and G1Na) and reinfused to monkeys after 10 Gy conditioning. G-CSF indicates granulocyte colony-stimulating factor; SCF, stem cell factor. (B) Timeline of the study. The animals received 3 Gy irradiation dose 2 years (96E019) and 3 years (96E025) after PBSCT. Blood samples (gray arrows) were collected for blood cell counts and granulocyte DNA (Gr DNA) isolation. The number of transduced clones contributing granulocyte production at each time point was determined by LAM-PCR analysis.