Fig. 5. SPECT imaging 1 h after injection of intravenously injected ^99mTc-labeled nanobodies. Both ^99mTc-NbCEA5 and ^99mTc-humanized CEA5 graft show high uptake in CEA-positive LS174T tumors in contrast to the ^99mTc-humanized scaffold alone. Adapted from ref. 73.