Localization of sarcoma xenografts in nude mice with indium-111-labeled monoclonal antibodies.
A labeling method utilizing modified carbohydrate moieties in antibody heavy chains as radionucleotide binding sites was evaluated. Murine anti-sarcoma monoclonal antibody (MAb 19-24) was labeled with Indium-111 (111In) using this technique and subcutaneous human sarcoma xenografts were successfully localized in nude mice. A nonspecific monoclonal antibody BL-3 was used as a negative control. Tumor-to-blood ratios of radioactivity in the mice injected with 111In-labeled MAb 19-24 were significantly (P < 0.05) higher than those obtained with nonspecific MAb BL-3. Calculations of percentage injected dose of radioactivity per gram tissue showed relatively high specific uptake of MAb 19-24 in sarcoma xenografts. Radioactivity cleared from the blood rapidly and hepatic uptake of 111In-labeled antibodies was found to be relatively low. Biodistribution studies in normal mice with 111In-labeled antibodies showed only blood pool activity with no significant concentration of activity into organs. Therefore, immunoreactivity of the antibodies was retained after 111In-labeling utilizing this new technique, allowing specific binding of radiolabeled MAb to tumor xenografts with relatively low hepatic uptake.
Chao
T C
TC
Department of Surgery, University of Illinois College of Medicine at Chicago.
Blend
M J
MJ
Lopes
A D
AD
Atcher
R W
RW
Das Gupta
T K
TK
Greager
J A
JA
D000818:Animals; D000911:Antibodies, Monoclonal / Q000097:blood / Q000378:metabolism; D000951:Antigens, Neoplasm / Q000276:immunology; D006801:Humans; D007205:Indium Radioisotopes; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009842:Oligopeptides; D004369:Pentetic Acid / Q000031:analogs & derivatives; D012513:Sarcoma, Experimental / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D013154:Spleen / Q000378:metabolism; D014018:Tissue Distribution; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D007205:Indium Radioisotopes; D009842:Oligopeptides; C062250:glycyl-tyrosyl-lysine-DTPA; D004369:Pentetic Acid