A triglycine linker improves tumor uptake and biodistributions of 67-Cu-labeled anti-neuroblastoma MAb chCE7 F(ab')2 fragments

Nucl Med Biol. 1999 Nov;26(8):943-50. doi: 10.1016/s0969-8051(99)00067-0.

Abstract

The peptide-linked copper chelators CPTA-triglycyl-L-p-isothiocyanato-phenylalanine (CPTA-R1-NCS) as well as DOTA-triglycyl-L-p-isocyanato-phenylalanine (DOTA-R1-NCS) were synthesized and coupled to F(ab')2 fragments of the anti-neuroblastoma monoclonal antibody (MAb) chCE7. 67Cu-labeled conjugates were compared with the original CPTA- and DO3A-F(ab')2 in vitro and in vivo in mice bearing neuroblastoma xenografts. With the CPTA-R1-F(ab')2, biodistributions were improved, because radioactivity present in the kidney was reduced. With the DOTA-R1-F(ab')2, clearance from the blood was slower and tumor uptake was higher compared with the other conjugates. DOTA-R1-F(ab')2 achieved the best tumor/tissue ratios.

MeSH terms

  • Animals
  • Antibodies, Monoclonal / chemistry
  • Antibodies, Monoclonal / pharmacokinetics*
  • Brain Neoplasms / metabolism*
  • Chromatography, Gel
  • Chromatography, High Pressure Liquid
  • Chromatography, Thin Layer
  • Copper Radioisotopes
  • Humans
  • Immunoconjugates / chemistry
  • Immunoconjugates / pharmacokinetics
  • Immunoglobulin Fab Fragments / chemistry*
  • Ligands
  • Mice
  • Mice, Nude
  • Neoplasm Transplantation
  • Neuroblastoma / metabolism*
  • Oligopeptides / chemistry*
  • Radiopharmaceuticals / chemistry
  • Radiopharmaceuticals / pharmacokinetics*
  • Spectrophotometry, Ultraviolet
  • Tissue Distribution

Substances

  • Antibodies, Monoclonal
  • Copper Radioisotopes
  • Immunoconjugates
  • Immunoglobulin Fab Fragments
  • Ligands
  • Oligopeptides
  • Radiopharmaceuticals
  • glycyl-glycyl-glycine