Fused Expression of
Anti-CEA Single-chain Antibody Gene with Core-streptavidin Gene in Insect Cells
YANG Wei-Dong, LI Biao, ZHU Cheng-Mo
( Ruijin hospital of Shanghai Second Medical University, Shanghai 200025,
China )
HE Hua-Jun, YANG Guan-Zhen, WU Xiang-Fu*
( Shanghai Institute of Biochemistry, the Chinese Academy of Sciences,
Shanghai 200031, China )
Abstract A fused
construct formed by an anti-CEA single-chain antibody gene with a
core-streptavidin gene(ScFv–CS)was inserted into the donor
plasmids pFastBacHTa and expressed in Tn-5B1-4 cells. SDS-PAGE analysis
revealed that the molecular weight expressed product of ScFv-CS were 41 kD.
Using horseradish peroxidase(HRP)labeled biotin as antibody product Western
blot, one band of 41 kD only was detected. It was also shown by RIA that the
expression product possessed the ability to bind to its specific antigen of
CEA. These results showed that the fusion protein not only had the ability to
bind CEA, but also could bind biotin specifically.
Key words carcino-embryonic antigen(CEA)；single-chain antibody；core-streptavidin；baculovirus expression
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