The stalk region of the influenza virus hemagglutinin is relatively well conserved compared with the globular head domain, which makes it a potential target for use as a universal vaccine against influenza. However, t...The stalk region of the influenza virus hemagglutinin is relatively well conserved compared with the globular head domain, which makes it a potential target for use as a universal vaccine against influenza. However, the role of CD4 T cells in the hemagglutinin stalk-specific immune response is not clear. Here we identified a mouse CD4 T-cell epitope that encompasses residues HA2113-131 from the hemagglutinin stalk domain after a sub-lethal infection of influenza. In response to stimulation with the identified epitope, splenocytes derived from the infected mice showed significant polyfunctionality as shown by IL-2, TNF-a and IFN-7 production as well as degranulation. Moreover, mice immunized with the peptide corresponding to this CD4 T-cell epitope exhibited interindividual sharing of the CD4 T-cell receptor I~ sequences, and they had a higher survival rate following a challenge with a lethal dose of pandemic H IN 1 influenza virus. Thus, our data demonstrated a crucial role of hemagglutinin stalk-specific CD4 T cells in the host immune resoonse a^ainst influenza virus infection.展开更多
文摘The stalk region of the influenza virus hemagglutinin is relatively well conserved compared with the globular head domain, which makes it a potential target for use as a universal vaccine against influenza. However, the role of CD4 T cells in the hemagglutinin stalk-specific immune response is not clear. Here we identified a mouse CD4 T-cell epitope that encompasses residues HA2113-131 from the hemagglutinin stalk domain after a sub-lethal infection of influenza. In response to stimulation with the identified epitope, splenocytes derived from the infected mice showed significant polyfunctionality as shown by IL-2, TNF-a and IFN-7 production as well as degranulation. Moreover, mice immunized with the peptide corresponding to this CD4 T-cell epitope exhibited interindividual sharing of the CD4 T-cell receptor I~ sequences, and they had a higher survival rate following a challenge with a lethal dose of pandemic H IN 1 influenza virus. Thus, our data demonstrated a crucial role of hemagglutinin stalk-specific CD4 T cells in the host immune resoonse a^ainst influenza virus infection.
