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Epitope-directed antibody selection by site-specific photocrosslinking.

ABSTRACT: Currently, there are no methods available offering solutions to select and identify antibodies binding to a specific conformational epitope of an antigen. Here, we developed a method to allow epitope-directed antibody selection from a phage display library by photocrosslinking bound antibodies to a site that specifically incorporates a noncanonical amino acid, p-benzoyl-l-phenylalanine (pBpa), on the target antigen epitope. By one or two rounds of panning against antibody phage display libraries, those hits that covalently bind to the proximity site of pBpa on specific epitopes of target antigens after ultraviolet irradiation are enriched and selected. This method was applied to specific epitopes on human interleukin-1? and complement 5a. In both cases, more than one-third of hits identified bind to the target epitopes, demonstrating the feasibility and versatility of this method.

SUBMITTER: Chen L

PROVIDER: S-EPMC7112767 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Epitope-directed antibody selection by site-specific photocrosslinking.

Chen Longxin L Zhu Chaoyang C Guo Hui H Li Runting R Zhang Limeng L Xing Zhenzhen Z Song Yue Y Zhang Zihan Z Wang Fuping F Liu Xiaofeng X Zhang Yuhan Y Ma Runlin Z RZ Wang Feng F

Science advances 20200401 14

Currently, there are no methods available offering solutions to select and identify antibodies binding to a specific conformational epitope of an antigen. Here, we developed a method to allow epitope-directed antibody selection from a phage display library by photocrosslinking bound antibodies to a site that specifically incorporates a noncanonical amino acid, <i>p</i>-benzoyl-l-phenylalanine (pBpa), on the target antigen epitope. By one or two rounds of panning against antibody phage display li ...[more]

PMID: 32270046

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