Figure 5. ^99mTc-labeled B6.3 diabody localised specifically to α_vβ₆-expressing tumors in vivo.

A) A375Pβ6 and A375Ppuro cells were injected subcutaneously on opposite shoulders and ^99mTc-labeled B6.3 diabody (approximately 11 µg, 30 MBq) was injected intravenously once tumours had developed. Mice were imaged by SPECT/CT as indicated 2 h, 5 h and 24 h after injection. B) SPECT/CT cross sections of the same mice at 2, 5 and 24 h. C) Percent injected doses of ^99mTc-labeled B6.3 diabody in A375Pβ6 and A375Ppuro tumours from three mice, obtained from these images. D) Biodistribution of ^99mTc-labeled B6.3 diabody 24 h after injection. Data expressed as % injected dose/g (%ID/g) as mean ± SD for 5 animals. Tumor-to blood ratios at this time point were 40.4 for A375Pβ6 tumors and 15.5 for A375Ppuro tumors. Significance assessed by Student's t-test.