Article

Broadly cross-reactive antibodies dominate the human B cell response against 2009 pandemic H1N1 influenza virus infection

Emory Vaccine Center, School of Medicine, Emory University, Atlanta, GA 30322, USA.
Journal of Experimental Medicine (Impact Factor: 13.91). 02/2011; 208(1):181-93. DOI: 10.1084/jem.20101352
Source: PubMed

ABSTRACT The 2009 pandemic H1N1 influenza pandemic demonstrated the global health threat of reassortant influenza strains. Herein, we report a detailed analysis of plasmablast and monoclonal antibody responses induced by pandemic H1N1 infection in humans. Unlike antibodies elicited by annual influenza vaccinations, most neutralizing antibodies induced by pandemic H1N1 infection were broadly cross-reactive against epitopes in the hemagglutinin (HA) stalk and head domain of multiple influenza strains. The antibodies were from cells that had undergone extensive affinity maturation. Based on these observations, we postulate that the plasmablasts producing these broadly neutralizing antibodies were predominantly derived from activated memory B cells specific for epitopes conserved in several influenza strains. Consequently, most neutralizing antibodies were broadly reactive against divergent H1N1 and H5N1 influenza strains. This suggests that a pan-influenza vaccine may be possible, given the right immunogen. Antibodies generated potently protected and rescued mice from lethal challenge with pandemic H1N1 or antigenically distinct influenza strains, making them excellent therapeutic candidates.

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Available from: Aneesh K Mehta, Jul 26, 2015
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    • "Recent studies aiming to characterize conserved epitopes of influenza virus revealed that specific regions in the HA stalk domain are highly preserved both in the structure and the sequence among various subtypes of viruses. It has been discovered that neutralizing antibodies to the HA stalk domain can be found after influenza infection (Wrammert et al., 2011) and vaccination (Corti et al., 2010). These anti-stalk antibodies demonstrate cross-reactivity between HAs of many strains from group 1 as well as from group 2 and it has been shown * e-mail: g.beata@biotech.ug.gda.pl "
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