3V6F

Crystal Structure of an anti-HBV e-antigen monoclonal Fab fragment (e6), unbound

3V6F の概要

• エントリーDOI: 10.2210/pdb3v6f/pdb
• 関連するPDBエントリー: 3V6Z
• 分子名称: Fab e6 Heavy Chain, Fab e6 Light Chain (3 entities in total)
• 機能のキーワード: immunoglobulin domain, antibody fab fragment, immune system
• 由来する生物種: Mus musculus; 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 192381.34

構造登録者

Dimattia, M.A.,Watts, N.R.,Stahl, S.J.,Grimes, J.M.,Steven, A.C.,Stuart, D.I.,Wingfield, P.T. (登録日: 2011-12-19, 公開日: 2013-02-06, 最終更新日: 2024-10-09)

主引用文献

Dimattia, M.A.,Watts, N.R.,Stahl, S.J.,Grimes, J.M.,Steven, A.C.,Stuart, D.I.,Wingfield, P.T.
Antigenic switching of hepatitis B virus by alternative dimerization of the capsid protein.
Structure, 21:133-142, 2013

PubMed Abstract: Chronic hepatitis B virus (HBV) infection afflicts millions worldwide with cirrhosis and liver cancer. HBV e-antigen (HBeAg), a clinical marker for disease severity, is a nonparticulate variant of the protein (core antigen, HBcAg) that forms the building-blocks of capsids. HBeAg is not required for virion production, but is implicated in establishing immune tolerance and chronic infection. Here, we report the crystal structure of HBeAg, which clarifies how the short N-terminal propeptide of HBeAg induces a radically altered mode of dimerization relative to HBcAg (∼140° rotation), locked into place through formation of intramolecular disulfide bridges. This structural switch precludes capsid assembly and engenders a distinct antigenic repertoire, explaining why the two antigens are cross-reactive at the T cell level (through sequence identity) but not at the B cell level (through conformation). The structure offers insight into how HBeAg may establish immune tolerance for HBcAg while evading its robust immunogenicity.

PubMed: 23219881
DOI: 10.1016/j.str.2012.10.017

実験手法

X-RAY DIFFRACTION (2.52 Å)