Longitudinal and integrative biomodeling of effector and memory immune compartments after inactivated influenza vaccination.

Most vaccines, including those against influenza, were developed by focusing solely on humoral response for protection. However, vaccination activates different adaptive compartments that might play a role in protection. We took advantage of the pandemic 2009 A(H1N1) influenza vaccination to conduct a longitudinal integrative multiparametric analysis of seven immune parameters in vaccinated subjects. A global analysis underlined the predominance of induction of humoral and CD4 T cell responses, whereas pandemic 2009 A(H1N1)-specific CD8 responses did not improve after vaccination. A principal component analysis and hierarchical clustering of individuals showed a differential upregulation of influenza vaccine-specific immunity including hemagglutination inhibition titers, IgA(+) and IgG(+) Ab-secreting cells, effector CD4 or CD8 T cell frequencies at day 21 among individuals, suggesting a fine-tuning of the immune parameters after vaccination. This is related to individual factors including the magnitude and quality of influenza-specific immune responses before vaccination. We propose a graphical delineation of immune determinants that would be essential for a better understanding of vaccine-induced immunity in vaccination strategies.