Comparative in vivo evaluation of technetium and iodine labels on an anti-HER2 affibody for single-photon imaging of HER2 expression in tumors.

Abstract

The use of Tc(I)-carbonyl chemistry enabled us to prepare a stable, site-specifically labeled 99mTc-His6-(ZHER2:4)2 conjugate that was able to bind to HER2-expressing cells in vitro and in vivo. The indirectly radioiodinated conjugate provided better tumor-to-liver ratios. The labeling of Affibody molecules with 99mTc should be investigated further.