Understanding the in vivo fate of radioimmunoconjugates for nuclear imaging

J Labelled Comp Radiopharm. 2018 Jul;61(9):672-692. doi: 10.1002/jlcr.3628. Epub 2018 May 14.


Over the past 25 years, antibodies have emerged as extraordinarily promising vectors for the delivery of radionuclides to tumors for nuclear imaging. While radioimmunoconjugates often produce very high activity concentrations in target tissues, they also are frequently characterized by elevated activity concentrations in healthy organs as well. The root of this background uptake lies in the complex network of biological interactions between the radioimmunoconjugate and the subject. In this review, we seek to provide an overview of these interactions and thus paint a general picture of the in vivo fate of radioimmunoconjugates. To cover the entire story, we have divided our discussion into 2 parts. First, we will address the path of the entire radioimmunoconjugate as it travels through the body. And second, we will cover the fate of the radionuclide itself, as its course can diverge from the antibody under certain circumstances. Ultimately, our goal is to provide the nuclear imaging field with a resource covering these important-yet often underestimated-pathways.

Keywords: FcRn; PET; SPECT; antibodies; copper-64; immunoPET; immunoSPECT; indium-111; monoclonal antibodies; pharmacodynamics; pharmacokinetics; positron emission tomography; radioimmunoconjugates; radioiodine; radiometals; single photon emission computed tomography; zirconium-89.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Antibodies / metabolism
  • Humans
  • Immunoconjugates* / metabolism
  • Immunoconjugates* / pharmacokinetics
  • Positron-Emission Tomography / methods*
  • Radioisotopes
  • Tissue Distribution
  • Tomography, Emission-Computed, Single-Photon / methods*


  • Antibodies
  • Immunoconjugates
  • Radioisotopes