tetano
Editor, Senior Moderator
J Virol. 2019 Jan 30. pii: JVI.01907-18. doi: 10.1128/JVI.01907-18. [Epub ahead of print]
[h=1]The molecular basis for antigenic drift of human A/H2N2 influenza viruses.[/h] Linster M[SUP]1[/SUP], Schrauwen EJA[SUP]1[/SUP], van der Vliet S[SUP]1[/SUP], Burke DF[SUP]2[/SUP], Lexmond P[SUP]1[/SUP], Bestebroer TM[SUP]1[/SUP], Smith DJ[SUP]2[/SUP], Herfst S[SUP]1[/SUP], Koel BF[SUP]1[/SUP], Fouchier RAM[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza A/H2N2 viruses caused a pandemic in 1957 and continued to circulate in humans until 1968. The antigenic evolution of A/H2N2 viruses over time and the amino acid substitutions responsible for this antigenic evolution are not known. Here, the antigenic diversity of a representative set of human A/H2N2 viruses isolated from 1957 until 1968 was characterized. Antigenic change of influenza A/H2N2 viruses during the 12 years that this virus circulated was modest. Two amino acid substitutions, T128D and N139K, located in the head domain of the H2 hemagglutinin molecule were identified as important determinants of antigenic change during A/H2N2 virus evolution. The rate of A/H2N2 virus antigenic evolution during the twelve-year period after introduction in humans was half of that of A/H3N2 viruses, despite similar rates of genetic change.IMPORTANCE While influenza A viruses of subtype H2N2 were at the origin of the Asian influenza pandemic, little is known about the antigenic changes that occurred during the twelve years of circulation in humans, the role of preexisting immunity and evolutionary rates of the virus. In this study, the antigenic map derived from hemagglutination inhibition titers of cell-cultured virus isolates and ferret post-infection sera displayed a directional evolution of viruses away from earlier isolates. Furthermore, individual mutations in close proximity to the receptor-binding site of the HA molecule determined the antigenic reactivity confirming that individual amino acid substitutions in A/H2N2 viruses can confer major antigenic changes. This study adds to our understanding of virus evolution with respect to antigenic variability, rates of virus evolution, and potential escape mutants of A/H2N2.
Copyright ? 2019 American Society for Microbiology.
PMID: 30700609 DOI: 10.1128/JVI.01907-18
[h=1]The molecular basis for antigenic drift of human A/H2N2 influenza viruses.[/h] Linster M[SUP]1[/SUP], Schrauwen EJA[SUP]1[/SUP], van der Vliet S[SUP]1[/SUP], Burke DF[SUP]2[/SUP], Lexmond P[SUP]1[/SUP], Bestebroer TM[SUP]1[/SUP], Smith DJ[SUP]2[/SUP], Herfst S[SUP]1[/SUP], Koel BF[SUP]1[/SUP], Fouchier RAM[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Influenza A/H2N2 viruses caused a pandemic in 1957 and continued to circulate in humans until 1968. The antigenic evolution of A/H2N2 viruses over time and the amino acid substitutions responsible for this antigenic evolution are not known. Here, the antigenic diversity of a representative set of human A/H2N2 viruses isolated from 1957 until 1968 was characterized. Antigenic change of influenza A/H2N2 viruses during the 12 years that this virus circulated was modest. Two amino acid substitutions, T128D and N139K, located in the head domain of the H2 hemagglutinin molecule were identified as important determinants of antigenic change during A/H2N2 virus evolution. The rate of A/H2N2 virus antigenic evolution during the twelve-year period after introduction in humans was half of that of A/H3N2 viruses, despite similar rates of genetic change.IMPORTANCE While influenza A viruses of subtype H2N2 were at the origin of the Asian influenza pandemic, little is known about the antigenic changes that occurred during the twelve years of circulation in humans, the role of preexisting immunity and evolutionary rates of the virus. In this study, the antigenic map derived from hemagglutination inhibition titers of cell-cultured virus isolates and ferret post-infection sera displayed a directional evolution of viruses away from earlier isolates. Furthermore, individual mutations in close proximity to the receptor-binding site of the HA molecule determined the antigenic reactivity confirming that individual amino acid substitutions in A/H2N2 viruses can confer major antigenic changes. This study adds to our understanding of virus evolution with respect to antigenic variability, rates of virus evolution, and potential escape mutants of A/H2N2.
Copyright ? 2019 American Society for Microbiology.
PMID: 30700609 DOI: 10.1128/JVI.01907-18