Molecular Analysis of Heavy Chain-Only Antibodies of Camelus bactrianus

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S. V. Tillib^1*, A. S. Vyatchanin¹, and S. Muyldermans^2,3

¹Institute of Gene Biology, Russian Academy of Sciences, ul. Vavilova 34/5, 119334 Moscow, Russia; fax: +7 (499) 135-4105; E-mail: tillib@genebiology.ru

²Laboratorium voor Cellulaire en Moleculaire Immunologie, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium; fax: +32 (0) 2-629-19-81; E-mail: svmuylde@vub.ac.be

³Structural Biology Research Center, Vlaams Interuniversitair Instituut voor Biotechnologie, Pleinlaan 2, B-1050 Brussel, Belgium

^* To whom correspondence should be addressed.

Received August 30, 2014

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In this work, IgG content and structures of antigen-binding domains and hinge regions of different IgG subtypes of Camelus bactrianus were analyzed in detail for the first time. Our data demonstrate that C. bactrianus contains a very large amount of heavy chain-only antibodies that can be used as a source of VHH domain-containing molecules. Despite some minor sequence differences identified in this study, C. bactrianus VHH domains possess principally the same unique features as those of C. dromedarius and the llama. These features are important for developing an efficient phage display-based antibody selection technology. We conclude that C. bactrianus is a very suitable animal to raise an immune response that serves as a source to identify antigen-specific VHHs selected after phage display.

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KEY WORDS: antibody, IgG, variable domain, single-domain antibody

DOI: 10.1134/S000629791412013X

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