title: High yield direct 76Br-bromination of monoclonal antibodies using chloramine-T.
abstract: Monoclonal antibody (MAb) A33 was labeled with the positron emitter 76Br (T(1/2) = 16.2 h). Direct labeling was done using the conventional chloramine-T method. After optimization of the labeling conditions, a maximum yield (mean +/- max error) of 77 +/- 2% was obtained at pH 6.8. In vitro binding of 76Br-A33 to SW1222 colonic cancer cells showed that the immunoreactivity was retained. Also, the MAbs 38S1 and 3S193 and the peptide hEGF were 76Br-labeled, resulting in labeling yields (mean +/- max error) of 75 +/- 3%, 63 +/- 4%, and 73 +/- 0.1%, respectively. We conclude that antibodies and peptides can be labeled conveniently with 76Br for the purpose of whole-body tumour imaging by positron emission tomography.
authors.affiliation: Department of Oncology, Radiology and Clinical Immunology, Uppsala University, Sweden. Johanna.Sundin@pet.uu.se
authors.forename: J
authors.initials: J
authors.lastname: Sundin
authors.forename: V
authors.initials: V
authors.lastname: Tolmachev
authors.forename: J
authors.initials: J
authors.lastname: Koziorowski
authors.forename: J
authors.initials: J
authors.lastname: Carlsson
authors.forename: H
authors.initials: H
authors.lastname: Lundqvist
authors.forename: S
authors.initials: S
authors.lastname: Welt
authors.forename: S
authors.initials: S
authors.lastname: Larson
authors.forename: A
authors.initials: A
authors.lastname: Sundin
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000276:immunology; D001967:Bromine Radioisotopes; D002021:Buffers; D002700:Chloramines / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007150:Immunohistochemistry; D007202:Indicators and Reagents; D007553:Isotope Labeling; D019275:Radiopharmaceuticals / Q000138:chemical synthesis*; D014105:Tosyl Compounds / Q000737:chemistry*; D014407:Tumor Cells, Cultured
chemical_list: D000911:Antibodies, Monoclonal; D001967:Bromine Radioisotopes; D002021:Buffers; D002700:Chloramines; D007202:Indicators and Reagents; D019275:Radiopharmaceuticals; D014105:Tosyl Compounds; C016300:chloramine-T