1. 99mTc-labeled chimeric anti-NCA 95 antigranulocyte monoclonal antibody for bone marrow imaging.
- Author
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Sarwar M, Higuchi T, Tomiyoshi K, Inoue T, Oriuchi N, Kbalil A, Alyafei S, Sakahara H, Chung JK, and Endo K
- Subjects
- Anemia, Aplastic diagnostic imaging, Anemia, Aplastic metabolism, Animals, Colorectal Neoplasms diagnostic imaging, Colorectal Neoplasms metabolism, Granulocytes metabolism, Humans, Iodine Radioisotopes pharmacokinetics, Isotope Labeling methods, Mice, Mice, Nude, Radionuclide Imaging, Technetium Tc 99m Medronate pharmacokinetics, Time Factors, Tissue Distribution, Antibodies, Monoclonal isolation & purification, Antibodies, Monoclonal pharmacokinetics, Antigens, Neoplasm, Bone Marrow diagnostic imaging, Cell Adhesion Molecules, Chimera immunology, Granulocytes immunology, Membrane Glycoproteins pharmacokinetics, Radiopharmaceuticals pharmacokinetics, Technetium Tc 99m Medronate analogs & derivatives
- Abstract
Chimeric mouse-human antigranulocyte monoclonal antibody (ch MAb) against non-specific cross-reacting antigen (NCA-95) was labeled with 99mTc (using a direct method) and 125I (using the chloramine T method), and its binding to human granulocytes and LS-180 colorectal carcinoma cells expressing carcinoembryonic antigen on their surfaces, cross-reactive with anti-NCA-95 chimeric monoclonal antibody, increased in proportion to the number of cells added and reached more than 80% and 90%, respectively. In biodistribution studies, 99mTc and 125I-labeled ch anti-NCA-95 MAb revealed high tumor uptake, and the tumor-to-blood ratio was 2.9 after 24 hours. The tumor-to-normal-organ ratio was also more than 3.0 in all organs except for the tumor-to-kidney ratio. Scintigrams of athymic nude mice confirmed the results of biodistribution studies that showed higher radioactivity in tumor and kidney of the mice administered with 99mTc-labeled ch MAb. A normal volunteer injected with 99mTc-labeled ch anti-NCA-95 antigranulocyte MAb showed clear bone marrow images, and a patient with aplastic anemia revealed irregular uptake in his lumbar spine, suggesting its utility for bone marrow scintigraphy and for the detection of hematological disorders, infections, and bone metastasis.
- Published
- 1998