Changes in CD69 expression on NK cells in response to influenza infection and vaccination.

<p>Dot plots represent (A), percentages and (B), absolute numbers of CD69+ NK cells from 17 subjects prior to influenza vaccination, and at day 1, 4 and 7 post-vaccination, 9 patients with acute seasonal influenza and 21 with acute 2009 pandemic H1N1 influenza virus infection. Complete blood counts at baseline were only available for 13 of the vaccinated subjects. (•, healthy subjects prior vaccination; ▪, healthy subjects post-vaccination; dark grey ▴, acutely infected with 2009 seasonal influenza strains; light grey ▴, acutely infected with 2009 pandemic H1N1 influenza virus). (C) Representative primary flow panels show percentages of CD69+ CD56<sup>bright</sup>, CD56<sup>dim</sup> and CD56<sup>neg</sup> NK cells prior to and 7 days post-vaccination and in seasonal and pandemic influenza infection. Percentages of CD69+ total NK cells are indicated.</p>