Variables affecting the tumor localization of /sup 131/I-antiferritin in experimental hepatoma

Journal Article · Wed Feb 01 04:00:00 EST 1984 · Am. J. Clin. Oncol.; (United States)

DOI:https://doi.org/10.1097/00000421-198402000-00002· OSTI ID:6748441

Rostock, R A; Klein, J L; Kopher, K A; Order, S E

Ferritin is both a normal tissue- and tumor-associated protein. The in vivo localization of /sup 131/I-radiolabeled antitumor ferritin and normal IgG antibodies in the H-4-II-E rat hepatoma model was investigated in both tumor and normal tissues over a dose range of 0.67 micrograms to 5 mg of normal and antiferritin IgG and at labeling ratios (microCi /sup 131/I per micrograms IgG) of 15:1, 5:1, and 1:10. The total dose from nonpenetrating radiation in rads was calculated and demonstrated a maximum of 2.9 times greater dose deposition (rads) of antiferritin than normal IgG in hepatoma without specific increase in binding in normal tissues. The maximum tumor targeting achieved was dependent on the amount of injected IgG and not on the labeling ratio or procedure. The binding in tumor could be inhibited by unlabeled antiferritin but not by unlabeled normal rabbit IgG and demonstrated the requirement of specificity for tumor binding. Normal tissues did not target with antiferritin. Most normal tissues have a capacity to bind normal and antiferritin IgG nonspecifically that is linear in relationship to the amount of injected IgG. The results demonstrate that /sup 131/I-antiferritin selectively targets ferritin-secreting hepatoma over normal tissues and that the amount of targeting is dependent on the amount of antiferritin injected. The physiologic reasons for such selective localization is not known, but the term ''biologic window'' has been used to describe the differential availability of tumor ferritin for binding.

• Research Organization: Johns Hopkins Hospital, Baltimore, MD
• OSTI ID: 6748441
• Journal Information: Am. J. Clin. Oncol.; (United States), Journal Name: Am. J. Clin. Oncol.; (United States) Vol. 7:1; ISSN AJCOD
• Country of Publication: United States
• Language: English

Related Subjects

550601 -- Medicine-- Unsealed Radionuclides in Diagnostics
560172* -- Radiation Effects-- Nuclide Kinetics & Toxicology-- Animals-- (-1987)
62 RADIOLOGY AND NUCLEAR MEDICINE
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHEMICAL BONDS
COMPLEXES
DAYS LIVING RADIOISOTOPES
DISEASES
DOSES
EXPERIMENTAL NEOPLASMS
FERRITIN
GLOBULINS
HEPATOMAS
IMMUNOGLOBULINS
INTERMEDIATE MASS NUCLEI
IODINE 131
IODINE ISOTOPES
IRON COMPLEXES
ISOTOPES
MAMMALS
METALLOPROTEINS
NEOPLASMS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PROTEINS
RADIATION DOSES
RADIOISOTOPES
RADIONUCLIDE KINETICS
RATS
RODENTS
SPECIFICITY
TRANSITION ELEMENT COMPLEXES
UPTAKE
VERTEBRATES