Tumor-Shed Antigen Affects Antibody Tumor Targeting: Comparison of Two ⁸⁹Zr-Labeled Antibodies Directed against Shed or Nonshed Antigens

Figure 4

Effect of mAb dose on accumulation of ⁸⁹Zr-mAb in nude mice ( = 5 per group) with A431/H9 tumor by PET analysis: (a) effect of amatuximab dose (10 µg and 60 µg) on accumulation of ⁸⁹Zr-amatuximab (2.96 MBq) in nude mice with tumor ( mm³; range: 253–599 mm³) for 10 µg amatuximab and ( mm³; range: 385–440 mm³) for 60 µg amatuximab. (b) Effect of B3 antibody dose (15 µg and 60 µg) on accumulation of ⁸⁹Zr-B3 (2.22 MBq) in nude mice with tumor ( mm³; range: 436–1042 mm³) for 15 µg B3 and ( mm³; range: 304–630 mm³) for 60 µg B3. The uptake value (%ID/g) was calculated by ROI analysis of PET images. Analysis of statistical significance in each organ uptake data (a) compared to the data from 10 µg for amatuximab or (b) 15 µg for B3. , , and .

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(b)