A method for direct quantification of the amount of DTPA in 111In monoclonal antibody preparations.
The bicyclic anhydride of DTPA-1-14C (BADTPA-1-14C) was synthesized and reacted with an antibody to human melanoma associated antigen (MAA) and with one to human class II major histocompatibility complex antigen (HLA-DR). DTPA-1-C incorporation per mole of anti MAA at molar ratios of 1:1 to 200:1 ranged from 0.5 to 25, while immunoreactivity ranged from 49 to 9%. With antibody to HLA-DR, results were similar. Anti MAA, but not anti HLA-DR, demonstrated polymerization upon conjugation. BADTPA-1-14C provides a convenient and accurate method for measuring the amount of DTPA in monoclonal antibody preparations and its effect on immunoreactivity.
D000911:Antibodies, Monoclonal / Q000302:isolation & purification*; D000951:Antigens, Neoplasm; D002460:Cell Line; D006681:HLA-D Antigens / Q000032:analysis*; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D007204:Indium / Q000032:analysis*; D008545:Melanoma / Q000276:immunology; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins / Q000032:analysis*; D004369:Pentetic Acid / Q000032:analysis*; D011868:Radioisotopes
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D006681:HLA-D Antigens; D006684:HLA-DR Antigens; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins; D011868:Radioisotopes; D007204:Indium; D004369:Pentetic Acid