TY - JOUR
T1 - Radiobromination of humanized anti-HER2 monoclonal antibody trastuzumab using N-succinimidyl 5-bromo-3-pyridinecarboxylate, a potential label for immunoPET
AU - Mume, Eskender
AU - Orlova, Anna
AU - Malmström, Per Uno
AU - Lundqvist, Hans
AU - Sjöberg, Stefan
AU - Tolmachev, Vladimir
N1 - Funding Information:
This work was financially supported by grants from the Swedish Cancer Society (Cancerfonden). The authors thank Prof. Jörgen Carlsson (Division of Biomedical Radiation Sciences, Uppsala University) for initiating research into tumor targeting using trastuzumab in our laboratories; his work has inspired this study among others. The authors also wish to thank the personnel of the Svedberg Laboratory, Uppsala, Sweden, and especially Mr. Lars Einarsson for technical support in radiobromine production.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2005/8
Y1 - 2005/8
N2 - Combining the specificity of radioimmunoscintigraphy and the high sensitivity of PET in an in vivo detection technique could improve the quality of nuclear diagnostics. Positron-emitting nuclide 76Br (T 1/2=16.2 h) might be a possible candidate for labeling monoclonal antibodies (mAbs) and their fragments, provided that the appropriate labeling chemistry has been established. For internalizing antibodies, such as the humanized anti-HER2 monoclonal antibody, trastuzumab, radiobromine label should be residualizing, i.e., ensuring that radiocatabolites are trapped intracellularly after the proteolytic degradation of antibody. This study evaluated the chemistry of indirect radiobromination of trastuzumab using N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate. Literature data indicated that the use of this method provided residualizing properties for iodine and astatine labels on some antibodies. An optimized "one-pot" procedure produced an overall labeling efficiency of 45.5±1.2% over 15 min. The bromine label was stable under physiological and denaturing conditions. The labeled trastuzumab retained its capacity to bind specifically to HER2-expressing SKOV-3 ovarian carcinoma cells in vitro (immunoreactivity more than 75%). However, in vitro cell test did not demonstrate that the radiobromination of trastuzumab using N-succinimidyl 5-bromo-3- pyridinecarboxylate improves cellular retention of radioactivity in comparison with the use of N-succinimidyl 4-bromobenzoate.
AB - Combining the specificity of radioimmunoscintigraphy and the high sensitivity of PET in an in vivo detection technique could improve the quality of nuclear diagnostics. Positron-emitting nuclide 76Br (T 1/2=16.2 h) might be a possible candidate for labeling monoclonal antibodies (mAbs) and their fragments, provided that the appropriate labeling chemistry has been established. For internalizing antibodies, such as the humanized anti-HER2 monoclonal antibody, trastuzumab, radiobromine label should be residualizing, i.e., ensuring that radiocatabolites are trapped intracellularly after the proteolytic degradation of antibody. This study evaluated the chemistry of indirect radiobromination of trastuzumab using N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate. Literature data indicated that the use of this method provided residualizing properties for iodine and astatine labels on some antibodies. An optimized "one-pot" procedure produced an overall labeling efficiency of 45.5±1.2% over 15 min. The bromine label was stable under physiological and denaturing conditions. The labeled trastuzumab retained its capacity to bind specifically to HER2-expressing SKOV-3 ovarian carcinoma cells in vitro (immunoreactivity more than 75%). However, in vitro cell test did not demonstrate that the radiobromination of trastuzumab using N-succinimidyl 5-bromo-3- pyridinecarboxylate improves cellular retention of radioactivity in comparison with the use of N-succinimidyl 4-bromobenzoate.
KW - Indirect radiobromination
KW - Monoclonal antibody
KW - N-Succinimidyl 5-bromo-3-pyridinecarboxylate
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U2 - 10.1016/j.nucmedbio.2005.04.010
DO - 10.1016/j.nucmedbio.2005.04.010
M3 - Article
C2 - 16026708
AN - SCOPUS:22144471159
VL - 32
SP - 613
EP - 622
JO - Nuclear Medicine and Biology
JF - Nuclear Medicine and Biology
SN - 0969-8051
IS - 6
ER -