FIGURE 2.  In vitro assessment of hNET-IRES-GFP reporter system. (A) Time–activity profiles of ¹²³I-MIBG accumulation (mL medium/g cells) in transduced C6 cells (closed diamond), Jurkat cells (open-crossed square), and COS-7 cells (open circle) and in corresponding wild-type cells (open diamond, closed square, and closed circle, respectively). Data were fitted to a 1-compartment model and yielded estimates of K₁, k₂, and V_d (Table 1). (B) ¹²³I-MIBG accumulation (V_d, Table 1) values vs. mean GFP expression values for pQcmv-hNET-IRES-GFP transduced C6 cells (closed diamond), Jurkat cells (open-crossed square), and COS-7 cells (open circle). (C) Western blot analysis for hNET and ß-actin proteins in hNET-IRES-GFP transduced C6 cells (band 2), COS-7 cells (band 4), and Jurkat cells (band 6) and in corresponding wild-type cells (bands 1, 3, and 5, respectively). SK-N-SH neuroblastoma cells served as positive control (band 7).