tetano
Editor, Senior Moderator
J Virol. 2010 Oct 27. [Epub ahead of print]
T cell mediated protection against lethal 2009 pandemic H1N1 influenza infection in a mouse model.
Guo H, Santiago F, Lambert K, Takimoto T, Topham DJ.
New York Influenza Center of Excellence, Department of Microbiology and Immunology, and the David H. Smith Center for Vaccine Biology and Immunology, Aab Institute of Biomedical Sciences, University of Rochester, Rochester, NY 14642.
Genetic mutation and reassortment of influenza gene segments, in particular hemagglutinin (HA) and neuraminidase (NA) that leads to antigenic drift and shift are the major strategies for influenza virus to escape pre-existing immunity. The most recent example of such phenomena is the first pandemic H1N1 influenza of the 21(st) century that started in 2009. Cross-reactive antibodies raised against H1N1 viruses circulating before 1930 show protective activity against the 2009 pandemic virus. Cross-reactive T cell responses can also contribute to protection, but in vivo support of this view is lacking. To explore the protection mechanisms in vivo, mice were primed with H1 and H3 influenza isolates and re-challenged with virus derived from 2009 H1N1 A/CA/04/09 virus, which was named as CA/E3/09. We found priming with influenza viruses of both H1 and H3 homo- and hetero-subtypes, protected against lethal CA/E3/09 virus challenge. Convalescent sera from these primed mice conferred no neutralization activity in vitro and no protection in vivo. However, T cell depletion studies suggested that both CD4 and CD8 T cells contribute to the protection. Taken together, these results indicate that cross-reactive T cells established after initial priming with distally related viruses can be a vital component for prevention from disease and control of pandemic H1N1 infection. Our results highlight the importance of establishing cross-reactive T cell responses for protecting against existing or new emerging pandemic influenza viruses.
http://www.ncbi.nlm.nih.gov/pubmed/20980523
T cell mediated protection against lethal 2009 pandemic H1N1 influenza infection in a mouse model.
Guo H, Santiago F, Lambert K, Takimoto T, Topham DJ.
New York Influenza Center of Excellence, Department of Microbiology and Immunology, and the David H. Smith Center for Vaccine Biology and Immunology, Aab Institute of Biomedical Sciences, University of Rochester, Rochester, NY 14642.
Genetic mutation and reassortment of influenza gene segments, in particular hemagglutinin (HA) and neuraminidase (NA) that leads to antigenic drift and shift are the major strategies for influenza virus to escape pre-existing immunity. The most recent example of such phenomena is the first pandemic H1N1 influenza of the 21(st) century that started in 2009. Cross-reactive antibodies raised against H1N1 viruses circulating before 1930 show protective activity against the 2009 pandemic virus. Cross-reactive T cell responses can also contribute to protection, but in vivo support of this view is lacking. To explore the protection mechanisms in vivo, mice were primed with H1 and H3 influenza isolates and re-challenged with virus derived from 2009 H1N1 A/CA/04/09 virus, which was named as CA/E3/09. We found priming with influenza viruses of both H1 and H3 homo- and hetero-subtypes, protected against lethal CA/E3/09 virus challenge. Convalescent sera from these primed mice conferred no neutralization activity in vitro and no protection in vivo. However, T cell depletion studies suggested that both CD4 and CD8 T cells contribute to the protection. Taken together, these results indicate that cross-reactive T cells established after initial priming with distally related viruses can be a vital component for prevention from disease and control of pandemic H1N1 infection. Our results highlight the importance of establishing cross-reactive T cell responses for protecting against existing or new emerging pandemic influenza viruses.
http://www.ncbi.nlm.nih.gov/pubmed/20980523