Identification of human vaccinees that possess antibodies targeting the egg-adapted hemagglutinin receptor binding site of an H1N1 influenza vaccine strain

Garretson, T. A.; Petrie, J. G.; Martin, E. T.; Monto, A. S.; Hensley, S. E.

doi:10.1101/249615

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bioRxiv · 10.1101/249615

Identification of human vaccinees that possess antibodies targeting the egg-adapted hemagglutinin receptor binding site of an H1N1 influenza vaccine strain

Garretson, T. A.·Petrie, J. G.·Martin, E. T.·Monto, A. S.·Hensley, S. E.

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Abstract

Human influenza viruses passaged in eggs often acquire mutations in the hemagglutinin (HA) receptor binding site (RBS). To determine if egg-adapted H1N1 vaccines commonly elicit antibodies targeting the egg-adapted RBS of HA, we completed hemagglutinin-inhibition assays with A/California/7/2009 HA and egg-adapted A/California/7/2009-X-179A HA using sera collected from 159 humans vaccinated with seasonal influenza vaccines during the 2015-16 season. We found that ~5% of participants had [≥]4-fold higher antibody titers to the egg-adapted viral strain compared to wild type viral strain. We used reverse-genetics to demonstrate that a single egg-adapted HA RBS mutation (Q226R) was responsible for this phenotype.

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Garretson, T. A., Petrie, J. G., Martin, E. T., Monto, A. S., Hensley, S. E.. 2018-01-17. Identification of human vaccinees that possess antibodies targeting the egg-adapted hemagglutinin receptor binding site of an H1N1 influenza vaccine strain. https://doi.org/10.1101/249615

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