Seasonal influenza vaccination of children induces humoral and cell-mediated immunity beyond the current season: Cross-reactivity with past and future strains

Academic Article


  • Background. Influenza viruses gradually accumulate point mutations, reducing the effectiveness of prior immune protection. Methods. Children aged 9-14 years received 2010-2011 trivalent inactivated influenza vaccine (TIV). Vaccination history, hemagglutination-inhibition (HI) titers, and cell-mediated immune responses were assessed to investigate the cross-reactivity with past and future influenza virus strains. Results. 2010-2011 TIV induced significant T-cell responses and HI titers of ≥160, with a fold-rise of ≥4 and titers of ≥100 maintained for >7 months in the majority of children. Pre-existing memory B cells in these children differentiated quickly to antibody-secreting cells to the new vaccine antigens. Children vaccinated in the previous year maintained high HI titers well into 2010, demonstrating elevated HI titers against A/Perth/16/2009, the future (in 2010-2011) H3N2 component. Prior vaccination enhanced CD8+ T-cell responses to A/Perth/16/2009. Children vaccinated with the prior 2009-2010 seasonal vaccine also demonstrated higher preexisting levels of interferon γ-secreting CD4+CD69+ T cells to 2009 pandemic influenza A(H1N1). Children previously vaccinated with 2009-2010 seasonal influenza vaccine also showed greater expansion of tumor necrosis factor α-secreting CD8+CD69+ T cells to 2009 pandemic influenza A(H1N1) upon vaccination in the 2010-2011 season than those who were not previously vaccinated. Conclusions. Seasonal influenza viruses continuously drift, which allows them to circumvent protective immunity, but conserved epitopes provide immunological cross-reactivity in children through either vaccination directly or through prime/boost in the prior influenza season.
  • Authors

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    Digital Object Identifier (doi)

    Author List

  • Reber AJ; Kim JH; Coleman LA; Spencer SM; Chung JR; Chen J; Gargiullo P; Sundaram ME; Belongia EA; Shay DK
  • Start Page

  • 1477
  • End Page

  • 1486
  • Volume

  • 214
  • Issue

  • 10