tetano
Editor, Senior Moderator
J Virol. 2012 Oct 31. [Epub ahead of print]
Sequential Seasonal H1N1 Influenza Virus Infections Protect Ferrets Against Novel 2009 H1N1 Influenza.
Carter DM, Bloom CE, Nascimento EJ, Marques ET, Craigo JK, Cherry JL, Lipman DJ, Ross TM.
Source
Center for Vaccine Research.
Abstract
Individuals <60 years of age had the lowest incidence of infection with ∼25% of these people having pre-existing, cross-reactive antibodies to novel 2009 H1N1 influenza. Many people >60 years old also had pre-existing antibodies to novel H1N1. These observations are puzzling because the seasonal H1N1 viruses circulating during the last 60 years were not antigenically similar to novel H1N1. We therefore hypothesized that a sequence of exposures to antigenically different seasonal H1N1 viruses could elicit an antibody response that protects against novel 2009 H1N1. Ferrets were pre-infected with seasonal H1N1 viruses and assessed for cross-reactive antibodies to novel H1N1. Serum from infected ferrets was assayed for cross-reactivity to both seasonal and novel 2009 H1N1 strains. These results were compared to ferrets that were sequentially infected with H1N1 viruses isolated prior to 1957 or more recently isolated viruses. Following seroconversion, ferrets were challenged with novel H1N1 influenza virus and assessed for viral titers in the nasal wash, morbidity, and mortality. There was no HAI cross-reactivity in ferrets infected with any single seasonal H1N1 influenza viruses with limited protection to challenge. However, sequential H1N1 influenza infections reduced the incidence of disease and elicited cross-reactive antibodies to novel H1N1 isolates. The amount and duration of virus shedding, and the frequency of transmission following novel H1N1 challenge, were reduced. Exposure to multiple seasonal H1N1 influenza viruses, not any single H1N1 influenza virus, elicits a breadth of antibodies that neutralize novel H1N1, even though the host was never exposed to the novel H1N1 influenza viruses.
PMID:
23115287
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23115287
Sequential Seasonal H1N1 Influenza Virus Infections Protect Ferrets Against Novel 2009 H1N1 Influenza.
Carter DM, Bloom CE, Nascimento EJ, Marques ET, Craigo JK, Cherry JL, Lipman DJ, Ross TM.
Source
Center for Vaccine Research.
Abstract
Individuals <60 years of age had the lowest incidence of infection with ∼25% of these people having pre-existing, cross-reactive antibodies to novel 2009 H1N1 influenza. Many people >60 years old also had pre-existing antibodies to novel H1N1. These observations are puzzling because the seasonal H1N1 viruses circulating during the last 60 years were not antigenically similar to novel H1N1. We therefore hypothesized that a sequence of exposures to antigenically different seasonal H1N1 viruses could elicit an antibody response that protects against novel 2009 H1N1. Ferrets were pre-infected with seasonal H1N1 viruses and assessed for cross-reactive antibodies to novel H1N1. Serum from infected ferrets was assayed for cross-reactivity to both seasonal and novel 2009 H1N1 strains. These results were compared to ferrets that were sequentially infected with H1N1 viruses isolated prior to 1957 or more recently isolated viruses. Following seroconversion, ferrets were challenged with novel H1N1 influenza virus and assessed for viral titers in the nasal wash, morbidity, and mortality. There was no HAI cross-reactivity in ferrets infected with any single seasonal H1N1 influenza viruses with limited protection to challenge. However, sequential H1N1 influenza infections reduced the incidence of disease and elicited cross-reactive antibodies to novel H1N1 isolates. The amount and duration of virus shedding, and the frequency of transmission following novel H1N1 challenge, were reduced. Exposure to multiple seasonal H1N1 influenza viruses, not any single H1N1 influenza virus, elicits a breadth of antibodies that neutralize novel H1N1, even though the host was never exposed to the novel H1N1 influenza viruses.
PMID:
23115287
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23115287