Figure 2.

MDA-MB-231 cells infected with GLV-1h153 demonstrate hNIS-specific ¹³¹I radioactivity uptake in cell culture. Left panel: MDA-MB-231 cells in culture were treated with GLV-1h153 (MOI 1) or medium with or without the hNIS-blocking agent, sodium perchlorate (NaClO₄). Radioactivity was measured 24 h after treatment. Right panel: Comparison between MDA-MB-231 treated with GLV-1h153 at an MOI of 1 for 24 h with or without NaClO₄. Infected MDA-MB-231 without NaClO₄ showed a >178-fold increase in ¹³¹I uptake (average level of 228.9 cpm/g protein; left panel, fourth bar). In comparison, infected cells with NaClO₄ (left panel, third bar) show significantly less background uptake (1.2 cpm/g), suggesting that virally mediated radioiodine uptake was hNIS specific. No radioiodine uptake was observed when cells were incubated with iodine without the virus. Thus, uninfected control cells (with or without NaClO₄) show only a background radioiodine uptake of <1 cpm/g protein.