Open AccessAntibodies Raised Against Chlamydial Lipopolysaccharide Antigens Reveal Convergence in Germline Gene Usage and Differential Epitope Recognition
Author(s) -
Cory L. Brooks,
Sven MüllerLoennies,
S.N. Borisova,
Lore Brade,
Paul Kosma,
Takashi Hirama,
Colin R. MacKenzie,
Helmut Brade,
Stephen V. Evans
Publication year - 2009
Publication title -
biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.43
H-Index - 253
eISSN - 1520-4995
pISSN - 0006-2960
DOI - 10.1021/bi9011308
Subject(s) - antigen , epitope , biology , antibody , germline , monoclonal antibody , gene , genetics , immune system , immunology
The structures of antigen-binding fragments from two related monoclonal antibodies have been determined to high resolution in the presence of several carbohydrate antigens raised against chlamydial lipopolysaccharide. With the exception of CDR H3, antibodies S54-10 and S73-2 are both derived from the same set of germline gene segments as the previously reported structures S25-2 and S45-18. Despite this similarity, the antibodies differ in specificity and the mechanism by which they recognize their cognate antigen. S54-10 uses an unrelated CDR H3 to recognize its antigen in a fashion analogous to S45-18; however, S73-2 recognizes the same antigen as S45-18 and S54-10 in a wholly unrelated manner. Together, these antibody-antigen structures provide snapshots into how the immune system uses the same set of inherited germline gene segments to generate multiple possible specificities that allow for differential recognition of epitopes and how unrelated CDR H3 sequences can result in convergent binding of clinically relevant bacterial antigens.