Fig. 2.

(a) Surface protein expression of 293T cells transfected to produce recombinant lentiviral vectors. 293T cells were transiently transfected with the lentiviral backbone plasmid FUGW, the antibody plasmid OKT3, the plasmid encoding antibody accessory proteins pIgαβ, the plasmid encoding a fusogen SV1, and other necessary packaging plasmids, to produce the targeting vector (FUGW/OKT3+fusogen). Co-transfection to produce vector bearing OKT3 only (FUGW/OKT3), bearing fusogen SV1 only (FUGW/fusogen), and bearing VSVG (FUGW/VSVG), were performed as controls. Two days post-transfection, GFP expression was analyzed by FACS (upper). Gating on the GFP-positive cells, the antibody and fusogen expressions were assessed by FACS staining using anti-human IgG and anti-HA tag antibodies, respectively (bottom). (b) FACS analysis of co-transfected vector-producing cells. 293T cells were transiently transfected with various plasmids as described above. Co-transfection using a non-relevant antibody lacking the binding specificity to CD3 (Ab), as well as co-transfection to produce vector bearing OKT3 only (FUGW/OKT3), and bearing VSVG (FUGW/VSVG), were performed as controls. Two days post-transfection, the antibody and fusogen expressions were measured by co-staining using anti-human IgG antibody and anti-HA tag antibody based on GFP positive cells by FACS.