tetano
Editor, Senior Moderator
J Gen Virol. 2014 Jul 30. pii: vir.0.067819-0. doi: 10.1099/vir.0.067819-0. [Epub ahead of print]
Epitope mapping of the 2009 pandemic and the A/Brisbane/59/2007 seasonal (H1N1) influenza virus hemagglutinins using monoclonal antibodies and escape mutants.
Retamal M1, Abed Y1, Corbeil J1, Boivin G2.
Author information
Abstract
Monoclonal antibodies (MAbs) constitute an important biological tool for influenza hemagglutinin (HA) epitope mapping through generation of escape mutants. The latter could provide insights into immune evasion mechanisms and such knowledge may benefit the future development of vaccines. Several influenza A(H1N1) pandemic 2009 (pdm09) HA escape mutants have been recently described. However, the HA antigenic sites of the previous seasonal A/Brisbane/59/2007 (H1N1) (Bris07) virus remain poorly documented. Herein, we produced MAbs against pdm09 and Bris07 HA proteins expressed in human HEK293 cells. Escape mutants were generated using MAbs that exhibited HA inhibition and neutralizing activities. The resulting epitope mapping of the pdm09 HA protein revealed 11 escape mutations including 3 that were previously described (G172E, N173D and K256E) and 8 novel ones (T89R, F128L, G157E, K180E, A212E, R269K, N311T, G478E). Among the 6 HA mutations that were part of predicted antigenic sites (Ca1, Ca2, Cb, Sa or Sb), 3 (G172E, N173D and K180E) were within the Sa site. Eight escape mutations (H54N, N55D, N55K, L60H, N203D, A231T, V314I, K464E) were obtained for Bris07 HA, and all but one (N203D, Sb site) were outside the predicted antigenic sites. Our results suggest that the Sa antigenic site is immunodominant in pdm09 HA, whereas the N203D mutation (Sb site), present in 3 different Bris07 escape mutants, appear as an immunodominant epitope in that strain. The fact that some mutations were not part of predicted antigenic sites reinforces the necessity of further characterizing the HA of additional H1N1 strains.
Copyright ? 2014, the Society for General Microbiology.
KEYWORDS:
H1N1; epitope; escape; hemagglutinin; influenza
PMID:
25078301
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25078301
Epitope mapping of the 2009 pandemic and the A/Brisbane/59/2007 seasonal (H1N1) influenza virus hemagglutinins using monoclonal antibodies and escape mutants.
Retamal M1, Abed Y1, Corbeil J1, Boivin G2.
Author information
Abstract
Monoclonal antibodies (MAbs) constitute an important biological tool for influenza hemagglutinin (HA) epitope mapping through generation of escape mutants. The latter could provide insights into immune evasion mechanisms and such knowledge may benefit the future development of vaccines. Several influenza A(H1N1) pandemic 2009 (pdm09) HA escape mutants have been recently described. However, the HA antigenic sites of the previous seasonal A/Brisbane/59/2007 (H1N1) (Bris07) virus remain poorly documented. Herein, we produced MAbs against pdm09 and Bris07 HA proteins expressed in human HEK293 cells. Escape mutants were generated using MAbs that exhibited HA inhibition and neutralizing activities. The resulting epitope mapping of the pdm09 HA protein revealed 11 escape mutations including 3 that were previously described (G172E, N173D and K256E) and 8 novel ones (T89R, F128L, G157E, K180E, A212E, R269K, N311T, G478E). Among the 6 HA mutations that were part of predicted antigenic sites (Ca1, Ca2, Cb, Sa or Sb), 3 (G172E, N173D and K180E) were within the Sa site. Eight escape mutations (H54N, N55D, N55K, L60H, N203D, A231T, V314I, K464E) were obtained for Bris07 HA, and all but one (N203D, Sb site) were outside the predicted antigenic sites. Our results suggest that the Sa antigenic site is immunodominant in pdm09 HA, whereas the N203D mutation (Sb site), present in 3 different Bris07 escape mutants, appear as an immunodominant epitope in that strain. The fact that some mutations were not part of predicted antigenic sites reinforces the necessity of further characterizing the HA of additional H1N1 strains.
Copyright ? 2014, the Society for General Microbiology.
KEYWORDS:
H1N1; epitope; escape; hemagglutinin; influenza
PMID:
25078301
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/25078301