Heterobifunctional reagents: A new approach to radiolabeling of monoclonal antibodies

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

OSTI ID:6852543

Wang, T S.T.; Ng, A K; Fawwaz, R A; Liu, Z; Alderson, P O

The use of bifunctional chelate such as the cyclic anhydride of DTPA for radiolabeling antibodies (Abs) may lead to homopolymerization, and intra- or intermolecular cross-linking, with resulting denaturation and decrease immunoreactivity of Abs. The authors, therefore, investigated the use of heterobifunctional reagents, whereby one group selectively couples to the amino group of the Ab and the other group to the radiometal for Ab labeling. One such reagent, 2,6-Dioxo-N-(carboxymethyl)morphine (DCM) was synthesized by reacting nitrilotriacetic acid with acetic anhydride. The other agent tested was commercially available N-Succinimidyl-3-(2-pyridyldithio) propionate (SPDP). These agents were evaluated independently for their ability to label a monoclonal antibody (MoAb) to a melanoma associated antigen (Ag). Labeling proceeded at a 2mg/ml concentration of the Ab, at HEPES pH 8.2, and 7.0, respectively, at room temperature for 30 min. The conjugate subsequently was labeled with Tc-99m or In-111. For comparison, the same labeled Abs also were prepared by using the cyclic anhydride of DTPA. Binding of the Ab to melanoma cells and control cells then was assayed. The results of cell binding experiments (N=3 per agent) in the region of Ag excess (X+-SD) were as follows: 62.6 +- 2.83% for Tc-99m-DCM-MoAb and 41.3+-1.84% for Tc-99m-SPDP-MoAb vs. 28.6 +- 1.16% for Tc-99m-DTPA-MoAb (p<0.01); 56.2 +- 2.97% for In-111-DCM-MoAb vs. 28.6 +- 1.16% for In-111-DTPA-M0Ab. Binding of all agents to the control lymphoid cell line was less than 3%. These results suggest that heterobifunctional reagents can reduce the loss of immunoreactivity of labeled MoAbs.

• Research Organization: Columbia Univ., New York, NY
• OSTI ID: 6852543
• 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

550604* -- Medicine-- Unsealed Radionuclides in Therapy-- (1980-)
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINO ACIDS
ANTIBODIES
ANTIGEN-ANTIBODY REACTIONS
ANTIGENS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CHELATING AGENTS
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DISEASES
DRUGS
DTPA
EVALUATION
HOURS LIVING RADIOISOTOPES
IMMUNOLOGY
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LABELLING
MEDICINE
MELANOMAS
MOLECULAR BIOLOGY
MONOCLONAL ANTIBODIES
NEOPLASMS
NUCLEAR MEDICINE
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PERFORMANCE TESTING
POLYMERIZATION
RADIOIMMUNOLOGY
RADIOIMMUNOTHERAPY
RADIOISOTOPES
RADIOLOGY
RADIOPHARMACEUTICALS
RADIOPROTECTIVE SUBSTANCES
RADIOTHERAPY
REACTION KINETICS
SYNTHESIS
TECHNETIUM 99
TECHNETIUM ISOTOPES
TESTING
THERAPY
TRACER TECHNIQUES
YEARS LIVING RADIOISOTOPES