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Updated: May 17, 2026
Peptide Scanning-assisted Identification of a Monoclonal Antibody-recognized Linear B-cell Epitope
Published on: March 24, 2017
[Epitope structure prediction of antigen B of Echinococcus granulosus and construction of multi-epitope recombinant
Li Jiang1, Yao-Guang Zhang, Shou-Fu Jiang
1Shanghai Municipal Center for Disease Control and Prevention, Shanghai Institutes of Preventive Medicine, Shanghai 200336, China. jlsh_819@163.com
Objective:
To improve the reactivity of Echinococcus granulosus antigen B (EgAgB) multi-epitope antigens using the gene fragment from 3 subunits, EgAgB1, EgAgB2, and EgAgB4.
Methods:
Discovery Studio Visualizer software and I-TASSER on-line server were used to predict protein structure gene sequence of the 3 subunits and their combinations in different way. The epitope or subunit combination higher prediction scores was selected for gene recombination. The target sequence was amplified with primers and by using overlap extension PCR technology. The target sequence was then cloned to pET32a constructing expression plasmid and expressing recombinant proteins. The expressed products were served recombinant antigens after purification. The immuno-response of the recombinant multi-epitope antigens were Western blotting analysis.
Results:
Structure prediction showed that all the three subunits EgAgB1, EgAgB4 are in a "Z" word structure. The epitope region is located in the central part of the sequence. For from the three subunits and four reactive epitopes (KK36, RK30, B4-2, and B4-3), 57 different combinations tried for structure prediction. Six of them were selected for recombination and expression. Western blotting six multi-epitope antigens (MEA-8, MEA-20, MEA-26, MEA-36, MEA-49, and MEA-52) suggested reactivity of multi-epitope antigen was much stronger than AgB subunit antigens when the positive echinococcosis were used.
Conclusion:
By using protein tertiary structural prediction and screening the higher prediction score of combinations, six multi-epitope recombinant antigens were constructed. Western blotting shows that the hand reactivity of multi-epitope antigen is much stronger than that of AgB subunit antigens.
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