Locking and blocking the viral landscape of an alphavirus with neutralizing antibodies

Jason Porta, Joyce Jose, John T. Roehrig, Carol D. Blair, Richard J. Kuhn, Michael G. Rossmann

Research output: Contribution to journalArticlepeer-review

45 Scopus citations


Alphaviruses are serious, sometimes lethal human pathogens that belong to the family Togaviridae. The structures of human Venezuelan equine encephalitis virus (VEEV), an alphavirus, in complex with two strongly neutralizing antibody Fab fragments (F5 and 3B4C-4) have been determined using a combination of cryo-electron microscopy and homology modeling. We characterize these monoclonal antibody Fab fragments, which are known to abrogate VEEV infectivity by binding to the E2 (envelope) surface glycoprotein. Both of these antibody Fab fragments cross-link the surface E2 glycoproteins and therefore probably inhibit infectivity by blocking the conformational changes that are required for making the virus fusogenic. The F5 Fab fragment cross-links E2 proteins within one trimeric spike, whereas the 3B4C-4 Fab fragment cross-links E2 proteins from neighboring spikes. Furthermore, F5 probably blocks the receptor-binding site, whereas 3B4C-4 sterically hinders the exposure of the fusion loop at the end of the E2 B-domain.

Original languageEnglish (US)
Pages (from-to)9616-9623
Number of pages8
JournalJournal of virology
Issue number17
StatePublished - 2014

All Science Journal Classification (ASJC) codes

  • Microbiology
  • Immunology
  • Insect Science
  • Virology


Dive into the research topics of 'Locking and blocking the viral landscape of an alphavirus with neutralizing antibodies'. Together they form a unique fingerprint.

Cite this