Three Types of Broadly Reacting Antibodies against Influenza B Viruses Induced by Vaccination with Seasonal Influenza Viruses.

Daisuke Hirano,Nobuko Ohshima,Gene Kurosawa,Yoshinobu Okuno,Yoshikazu Kurosawa,Ritsuko Kubota-Koketsu,Ayami Yamasaki,Shunji Yoshida

doi:10.1155/2018/7251793

Abstract

We analyzed the antibody (Ab) repertoire against influenza B viruses induced by vaccination with seasonal influenza viruses in one individual who had never been vaccinated until 2009. The vaccine used in this study comprised B/Massachusetts/2/2012 (Yamagata lineage), A/Texas/50/2012 (H3N2), and A/California/7/2009 (H1N1). One month after the subject received two vaccinations, blood (200 ml) was obtained and peripheral mononuclear cells were prepared, and a large Ab library was constructed using phage display technology. The library was screened with HA-enriched fraction of B/Massachusetts/2/2012 and B/Brisbane/60/2008 (Victoria lineage) virus, and a total of 26 Abs that potentially bound to hemagglutinin (HA) molecules were isolated. Their binding activities to six influenza B viruses, three of Yamagata lineage and three of Victoria lineage, and two influenza A viruses, H1N1 and H3N2, were examined. The Abs showed cross-reactivity at three different levels. The first type bound to all Yamagata lineage viruses. The second type bound to both Yamagata and Victoria lineage viruses. The third type bound to both influenza A and B viruses. These results indicate that common epitopes exist on HA molecules of influenza virus at various levels, and humans have capability to produce Abs that bind to such common epitopes.

Highlights

Influenza is an infectious disease of the respiratory tract that affects millions of people annually [1]
When the amino acid sequences were compared between Yamagata lineage viruses and Victoria lineage viruses, large differences were found in five regions, 71–81, 116–137, 146–150, 162a–174, and 196–208
While three loops and one helix regions located in the surrounding region of the receptor-binding pocket are highly immunogenic, 63% of isolated clones in the present study belonged to GC1 (Table 1)

Summary

Introduction

Influenza is an infectious disease of the respiratory tract that affects millions of people annually [1]. Since antibodies (Abs) play important roles in protection against influenza virus, preventive vaccines have been considered one of the most efficient measures to control viral infection [2]. Hemagglutinin (HA) is the main target of influenza virus-neutralizing Abs. viruses can acquire mutations in the epitopes recognized by such Abs, leading to viral escape and a potential epidemic in the following year. Vaccine strains need to be changed almost annually to remain effective. As long as the vaccine strain is a good match for the circulating virus, vaccination is effective for preventing viral infection [3]. The mode of response against influenza virus infection seems to be heterogeneous among humans [4]. Some individuals do not contact influenza without vaccination for a long time, whereas others often contact influenza

Methods

Discussion

Conclusion