Experimental design.

Rhesus macaques underwent mobilization with SCF and GM-CSF for 5 consecutive days. The mobilized progenitors were collected by apheresis and enriched for primitive progenitors by CD34 selection. The CD34-enriched cells were split into 2 equal fractions and then transduced daily for 4 days with either of 2 equivalent titer retroviral vectors carrying the neomycin resistance gene, both in the presence of IL-3–IL-6–SCF–FLT and either autologous stroma or the CH-296 fibronectin fragment (Retronectin). Transduced cells were collected and infused simultaneously after conditioning with 5 Gy twice. Bone marrow mononuclear cells were collected at regular time points after transplantation and plated in CFU assays with and without G418. Well-isolated G418-resistant colonies were plucked and screened by neo PCR for the vector-positive clones and were subjected to integration site analysis. Peripheral blood mononuclear cells were obtained, and limiting dilution T and B cell populations were generated by sorting for CD2⁺ and CD20⁺ populations