Intraperitoneal radio-localization of tumors pre-targeted by biotinylated monoclonal antibodies

Int J Cancer. 1990 Jun 15;45(6):1184-9. doi: 10.1002/ijc.2910450632.

Abstract

We describe 2-step and 3-step strategies for intraperitoneal tumor radio-localization by means of monoclonal antibodies (MAbs). Nude mice bearing intraperitoneal human colon carcinoma tumors were injected i.p. with biotinylated MAb AUAI, followed 24 hr later by radioiodinated streptavidin (2-step). The uptake of radioactivity in tumor and normal tissues was measured 4 hr after injection of radioactive compound. A 3-step strategy consisted in administering biotinylated antibody, cold avidin after 24 hr and 111In-labelled biotin after a further 4 hr; mice were then killed 2 hr later. Tumor localization of intraperitoneally-administered biotinylated antibody and direct targeting of radioactive streptavidin to biotinylated antibody bound to tumor sites were demonstrated using immunohistochemistry and autoradiography. Our results show that (i) the 2-step approach increased the percentage of radioactivity uptake by tumor with respect to directly labelled antibodies (24% vs. 6%) and improved the tumor/non-tumor ratio; (ii) the 3-step approach allowed faster blood clearance of the radioactive probe (111In-biotin) and yielded high tumor/non-tumor ratios. "Pre-targeting" methods appear to have advantages over the conventional 1-step approach with directly radiolabelled antibody.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Antibodies, Monoclonal* / administration & dosage
  • Autoradiography
  • Avidin / administration & dosage
  • Avidin / toxicity
  • Bacterial Proteins / administration & dosage
  • Biotin* / administration & dosage
  • Cell Line
  • Drug Evaluation, Preclinical
  • Immunohistochemistry
  • Indium Radioisotopes / administration & dosage
  • Iodine Radioisotopes / administration & dosage
  • Isotope Labeling / methods
  • Mice
  • Mice, Nude
  • Neoplasm Transplantation
  • Peritoneal Neoplasms / diagnostic imaging*
  • Radionuclide Imaging
  • Streptavidin
  • Time Factors
  • Transplantation, Heterologous

Substances

  • Antibodies, Monoclonal
  • Bacterial Proteins
  • Indium Radioisotopes
  • Iodine Radioisotopes
  • Avidin
  • Biotin
  • Streptavidin