tetano
Editor, Senior Moderator
Vet Microbiol. 2016 Feb 1;183:103-9. doi: 10.1016/j.vetmic.2015.12.005. Epub 2015 Dec 12.
[h=1]Different counteracting host immune responses to clade 2.2.1.1 and 2.2.1.2 Egyptian H5N1 highly pathogenic avian influenza viruses in na?ve and vaccinated chickens.[/h] Samy AA[SUP]1[/SUP], El-Enbaawy MI[SUP]2[/SUP], El-Sanousi AA[SUP]3[/SUP], Nasef SA[SUP]1[/SUP], Naguib MM[SUP]1[/SUP], Abdelwhab EM[SUP]4[/SUP], Hikono H[SUP]5[/SUP], Saito T[SUP]6[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] In Egypt, two distinct lineages of H5N1 highly pathogenic avian influenza (HPAI) viruses, "classic 2.2.1.2" and "variant 2.2.1.1" strains, have evolved. The underlying host immune responses counteracting these viruses in chickens remain not well understood. In the present study, the cytokine responses to a classic strain (C121) and those to a variant strain (V1063) were compared in na?ve and vaccinated chickens. In na?ve chickens, the C121 replicated more efficiently than the V1063. Both the C121 and the V1063 increased interferon (IFN)-γ and interleukin (IL)-10 gene expression at 48h post inoculation (hpi) in the lung and spleen but the levels of these cytokines were lower in chickens infected with the C121 than those infected with the V1063. In contrast, in chickens vaccinated with inactivated C121-based vaccine, the C121 replicated less than the V1063. Both challenge with the C121 and that with the V1063 did not increase IFN-γ gene expression at 48 hpi; rather, the C121 increased IL-4 gene expression in the lung accompanied with lower viral titer and higher HI titers. These results suggested that the pathogenicity of HPAI viruses correlated with IFN-γ-producing helper and/or cytotoxic T cell responses in na?ve chickens, whereas vaccine efficacy to HPAI viruses correlated with IL-4 producing helper T cell responses in the lung in vaccinated chickens. It implies that IL-4 in the lung, in addition to the traditional serum HI titers, could be used to screen novel vaccine strategies, such as strains, adjuvant, prime/boost protocols, against HPAI in chickens.
Copyright ? 2015 Elsevier B.V. All rights reserved.
[h=4]KEYWORDS:[/h] Avian influenza; Chickens; Cytokine; Egypt; H5N1; Vaccine
PMID: 26790942 [PubMed - in process]
[h=1]Different counteracting host immune responses to clade 2.2.1.1 and 2.2.1.2 Egyptian H5N1 highly pathogenic avian influenza viruses in na?ve and vaccinated chickens.[/h] Samy AA[SUP]1[/SUP], El-Enbaawy MI[SUP]2[/SUP], El-Sanousi AA[SUP]3[/SUP], Nasef SA[SUP]1[/SUP], Naguib MM[SUP]1[/SUP], Abdelwhab EM[SUP]4[/SUP], Hikono H[SUP]5[/SUP], Saito T[SUP]6[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] In Egypt, two distinct lineages of H5N1 highly pathogenic avian influenza (HPAI) viruses, "classic 2.2.1.2" and "variant 2.2.1.1" strains, have evolved. The underlying host immune responses counteracting these viruses in chickens remain not well understood. In the present study, the cytokine responses to a classic strain (C121) and those to a variant strain (V1063) were compared in na?ve and vaccinated chickens. In na?ve chickens, the C121 replicated more efficiently than the V1063. Both the C121 and the V1063 increased interferon (IFN)-γ and interleukin (IL)-10 gene expression at 48h post inoculation (hpi) in the lung and spleen but the levels of these cytokines were lower in chickens infected with the C121 than those infected with the V1063. In contrast, in chickens vaccinated with inactivated C121-based vaccine, the C121 replicated less than the V1063. Both challenge with the C121 and that with the V1063 did not increase IFN-γ gene expression at 48 hpi; rather, the C121 increased IL-4 gene expression in the lung accompanied with lower viral titer and higher HI titers. These results suggested that the pathogenicity of HPAI viruses correlated with IFN-γ-producing helper and/or cytotoxic T cell responses in na?ve chickens, whereas vaccine efficacy to HPAI viruses correlated with IL-4 producing helper T cell responses in the lung in vaccinated chickens. It implies that IL-4 in the lung, in addition to the traditional serum HI titers, could be used to screen novel vaccine strategies, such as strains, adjuvant, prime/boost protocols, against HPAI in chickens.
Copyright ? 2015 Elsevier B.V. All rights reserved.
[h=4]KEYWORDS:[/h] Avian influenza; Chickens; Cytokine; Egypt; H5N1; Vaccine
PMID: 26790942 [PubMed - in process]