Potential usefulness of 99mTc-labeled monoclonal antibody A7 for immunoscintigraphy of human pancreatic carcinoma.
BACKGROUND
To improve survival rates of patients with pancreatic carcinoma, it is critical to develop new technology for early and certain diagnosis. One possibility is the application of radioimmunoscintigraphy using radiolabeled monoclonal antibodies.


METHODS
Monoclonal antibody A7 (Mab A7) was labeled with technetium-99m (99mTc) and injected into athymic nude mice bearing human pancreatic carcinoma xenografts in order to examine its usefulness for radioimmunoscintigraphy.


RESULTS
The binding activity of 99mTc labeled Mab A7 was nearly identical to that of non-labeled Mab A7. When 99mTc-labeled Mab A7 was injected intravenously into tumor-bearing nude mice, tumor accumulation of 99mTc-labeled Mab A7 increased until 24 hours after injection and then decreased slowly. The tumor tissue/blood ratio of radioactivity was significantly greater than that of normal mouse IgG.


CONCLUSIONS
These results suggest that 99mTc-labeled Mab A7 is suitable for radioimmunoscintigraphy of human pancreatic carcinoma.
Matsumura
H
H
Department of Surgery, Kyoto Prefectural University of Medicine, Japan.
Otsuji
E
E
Kobayashi
S
S
Okamoto
K
K
Toma
A
A
Yamagishi
H
H
D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism / Q000493:pharmacokinetics; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D018796:Immunoconjugates / Q000493:pharmacokinetics; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism; D016719:Radioimmunodetection / Q000379:methods; D013667:Technetium / Q000493:pharmacokinetics; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D018796:Immunoconjugates; D013667:Technetium