TY - JOUR
T1 - Use of a HEHEHE purification tag instead of a hexahistidine tag improves biodistribution of affibody molecules site-specifically labeled with 99mTc, 111In, and 125I
AU - Hofström, Camilla
AU - Orlova, Anna
AU - Altai, Mohamed
AU - Wangsell, Fredrik
AU - Gräslund, Torbjörn
AU - Tolmachev, Vladimir
N1 - Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2011/6/9
Y1 - 2011/6/9
N2 - Affibody molecules are a class of small (̃7 kDa) robust scaffold proteins suitable for radionuclide molecular imaging in vivo. The attachment of a hexahistidine (His6)-tag to the Affibody molecule allows facile purification by immobilized metal ion affinity chromatography (IMAC) but leads to high accumulation of radioactivity in the liver. Earlier, we have demonstrated that replacement of the His6-tag with the negatively charged histidine-glutamate-histidine-glutamate-histidine-glutamate (HEHEHE)-tag permits purification of Affibody molecules by IMAC, enables labeling with [ 99mTc(CO)3]+, and provides low hepatic accumulation of radioactivity. In this study, we compared the biodistribution of cysteine-containing Affibody molecules site-specifically labeled with 111In, 99mTc, and 125I at the C-terminus, having a His6-tag at the N- or C-terminus or a HEHEHE-tag at the N-terminus. We show that the use of a HEHEHEtag provides appreciable reduction of hepatic radioactivity, especially for radiometal labels. We hope that this information can also be useful for development of other scaffold protein-based imaging agents.
AB - Affibody molecules are a class of small (̃7 kDa) robust scaffold proteins suitable for radionuclide molecular imaging in vivo. The attachment of a hexahistidine (His6)-tag to the Affibody molecule allows facile purification by immobilized metal ion affinity chromatography (IMAC) but leads to high accumulation of radioactivity in the liver. Earlier, we have demonstrated that replacement of the His6-tag with the negatively charged histidine-glutamate-histidine-glutamate-histidine-glutamate (HEHEHE)-tag permits purification of Affibody molecules by IMAC, enables labeling with [ 99mTc(CO)3]+, and provides low hepatic accumulation of radioactivity. In this study, we compared the biodistribution of cysteine-containing Affibody molecules site-specifically labeled with 111In, 99mTc, and 125I at the C-terminus, having a His6-tag at the N- or C-terminus or a HEHEHE-tag at the N-terminus. We show that the use of a HEHEHEtag provides appreciable reduction of hepatic radioactivity, especially for radiometal labels. We hope that this information can also be useful for development of other scaffold protein-based imaging agents.
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U2 - 10.1021/jm200065e
DO - 10.1021/jm200065e
M3 - Article
C2 - 21524142
AN - SCOPUS:79958148943
VL - 54
SP - 3817
EP - 3826
JO - Journal of Medicinal Chemistry
JF - Journal of Medicinal Chemistry
SN - 0022-2623
IS - 11
ER -