Construction of an antigenic map of the haemagglutinin-esterase protein of influenza C virus

Abstract

Four different antigenic sites (A-l, A-2, B-I, B-2) have been identified previously on the haemagglutininesterase (HE) glycoprotein of influenza C/Ann Arbor/I/50 virus with seven monoclonal antibodies (MAbs). In this study we produced 30 additional anti-HE MAbs, nine of which demonstrated at least one of the following activities: haemagglutination inhibition, receptor-destroying enzyme inhibition, haemolysis inhibition, and neutralization (group A). The remaining had none of these activities (group B). These antibodies, and those previously isolated, were used to construct a more complete antigenic map of the HE molecule.Operational and topological analyses showed that a minimum of nine non-overlapping or partially overlapping antigenic sites were present on the HE protein, five recognized by group A MAbs (A-1 to A-5) and four by group B (B-1 to B-4). Among these antigenic sites, site A-5 was unique in that MAbs to this site inhibited the receptor-destroying activity without influencing the receptor-binding activity, which supports the idea that the sites responsible for these two functions are separate. It was also found that several group B MAbs were crossreactive with host cell antigens.

Antigenic and Genetic Characterization of Influenza C Viruses Which Caused Two Outbreaks in Yamagata City, Japan, in 1996 and 1998

“…The 33 influenza C virus strains isolated in Yamagata City in 1996 and 1998 were examined in HI tests for reactivity with four different anti-HE MAbs characterized previously (30,31). As shown in Table 1, the reactivity patterns of the 1996 and 1998 isolates were similar; all the viruses were highly reactive with MAbs J14 and Q5 but were unreactive or very weakly reactive with U4 and MS22.…”

“…The hemagglutination inhibition (HI) test was done in microtiter plates with anti-HE monoclonal antibodies (MAbs) (30,31) and 0.5% chicken erythrocytes. Briefly, 50 l of 16 hemagglutinating units (HAU) of virus suspension per ml was added to each well containing 50 l of twofold-diluted MAbs.…”

Frequent Reassortment among Influenza C Viruses

“…Antigenic analysis of influenza C viruses isolated in Sendai City between 1990 and 1999. The 45 influenza C virus strains isolated in Sendai City between 1990 and 1999 were examined in HI tests for reactivity with four different anti-HE MAbs characterized previously (30,31). Antigenicity of all the isolates and HI titers of the representative strains were shown in Fig.…”

The Dominant Antigenic Group of Influenza C Infections Changed from C/Sao Paulo/378/82-Lineage to C/Kanagawa/1/76-Lineage in Yamagata, Japan, in 2014

“…In particular, for the isolation of influenza virus C, we obtained nasopharyngeal specimens from persons who visited one of two pediatric outpatient clinics in Yamagata city or Yamanobe town in Yamagata Prefecture, as described previously (7). Of the 6 distinct virus groups (C/Taylor/1233/47-lineage, C/Kanagawa/1/ 76-lineage, C/Mississippi/80-lineage, C/Yamagata/26/ 81-lineage, C/Aichi/1/81-lineage, and C/Sao Paulo/ 378/82-lineage) categorized on the basis of antigenic analysis by the hemagglutination-inhibition test using monoclonal antibodies against the hemagglutininesterase (HE) glycoprotein (7,8) (7). In 2012, we isolated not only 23 C/Sao Paulo/378/82-lineage strains but also 6 C/Kanagawa/1/76-lineage strains ( Fig.…”