Antigenic heterogeneity among phylogenetic clusters of influenza D viruses

Abstract

Influenza (flu) D virus, a possible causative agent of bovine respiratory disease, is genetically classified into three clusters: D/OK-, D/660-, and D/Japan-lineages. To evaluate antigenic heterogeneity among these clusters, we compared antibody titers to each lineage virus using bovine sera collected over time following virus infection. Antibody titers to D/Japan-lineage virus rose rapidly in the acute phase of infection, and were 4 times higher than those to the other clustered viruses. In the later phase of infection, titers to D/Japan-lineage virus were equivalent to those to D/OK-lineage virus, and still higher than those to D/660-lineage virus. These results suggest the existence of common and lineage-specific antigenic epitopes in the hemagglutinin-esterase-fusion protein of flu D viruses.

Influenza D Virus: Serological Evidence in the Italian Population from 2005 to 2017

“…At least three antigenic lineages of IDV have been identified-D/Oklahoma, D/660 and D/Japan-and HI analysis have shown up to a 10-fold loss in cross-reactivity against heterologous antiserum [8,39,40]. Serological analysis in this study has been conducted using D/660-like strain; however, the use of a single IDV strain may ultimately lead to an underestimation of the true seroprevalence in Italian population, leaving the conclusions of this study unchanged.…”

Detection of a New Genetic Cluster of Influenza D Virus in Italian Cattle

“…The circulation of influenza D virus (IDV) has been detected in a wide range of animal species and has been increasingly reported all over the world since its discovery in 2011 [1,2]. Cattle are considered the major viral reservoir.…”

“…Based on the hemagglutinin-esterase (HEF) gene, at least three main genetic and antigenic clusters have been identified: D/OK distributed worldwide, D/660 detected only in the USA, and D/Japan in Japan [2]. Since 2014, the co-circulation of two distinct genetically and antigenically lineages have been reported in the USA.…”

The first decade of research advances in influenza D virus

“…htm). IDV can be genetically classified into four lineages: D/OK, D/660, D/Yama2016 and D/Yama2019, based on the hemagglutinin-esterase-fusion (HEF) gene [5,6], which is the primary target of neutralizing antibodies generated during IDV infection.…”