Employment of a macrocyclic amine bifunctional chelate to label antibodies

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:7030841

Franz, J; Barefield, E K; Freeman, G M; Volkert, W A; Holmes, R A

Conjugation of antibodies (ABs) with bifunction chelates (BFCs) is an effective method to produce immunodiagnostic and immunotherapeutic agents. Most BFCs employ multidentate acetate ligands to chelate metallic radionuclides. The authors have designed a BFC where a cyclam analogue tetradentate macrocyclic amine (MA) is the complexing moiety, MA was linked to the AB using a 3 step process. The epsilon-amine groups on the AB was conjugated using m-maleimidobenzoyl-N-hydroxysuccinimide ester. A MA derivative with a free thiol group was added to produce the final product. The conjugated AB was used to bind Cu-64 (tl/2=12hr). Cu-64 was used because of its availability and because its analog Cu-67 can be used therapeutically. The effects of conjugation and radiolabeling on the denaturation of rabbit-anti-HSA antibodies were determined by affinity chromatography and molecular exclusion HPLC. Non-specific binding (NSB) was minimized by washing the labeled conjugated ABs bound to a Sepharose-HSA affinity column with 1 mM EDTA. No exchange of Cu-64 from the MA to EDTA occured in greater than or equal to 72 hrs while most NSB Cu-64 was exchangeable. An average of 0.5 +- 0.2 BFC groups per AB can be conjugated with 65% active AB remaining. A series of experiments demonstrated that labeling the BFC with Tc-99m prior to conjugation was effective in attaching Tc-99m to the ABs with less than or equal to 10% denaturation. These results indicate the efficacy of MA based BFCs for producing radiocopper and Tc-99m labeled ABs.

• Research Organization: Univ. of Missouri and H.S. Truman Veterans Hospital, Columbia, MO
• OSTI ID: 7030841
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400700 -- Radiochemistry & Nuclear Chemistry
550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINES
ANIMALS
ANTIBODIES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BINDING ENERGY
CHELATES
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CHEMISTRY
CHROMATOGRAPHY
CLEANING
COMPLEXES
COPPER 64
COPPER 67
COPPER ISOTOPES
CROSS-LINKING
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENERGY
ESTERS
HOURS LIVING RADIOISOTOPES
IMMUNOASSAY
IMMUNOLOGY
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LABELLING
LIGANDS
MAMMALS
NUCLEI
ODD-EVEN NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
POLYMERIZATION
RABBITS
RADIOASSAY
RADIOCHEMISTRY
RADIOIMMUNOASSAY
RADIOIMMUNOLOGY
RADIOISOTOPES
RADIOPHARMACEUTICALS
SEPARATION PROCESSES
TECHNETIUM 99
TECHNETIUM ISOTOPES
THIOLS
TRACER TECHNIQUES
VERTEBRATES
WASHING
YEARS LIVING RADIOISOTOPES