Figure 1.

Study design. Blood samples are obtained before (d0) and 28±7 days (d28) after a single intramuscular inoculation of the seasonal inactivated influenza vaccine. Samples from d0 are used for gene expression analysis, hemagglutinin 20-mer peptide microarrays, determination of serum cytokines and chemokines, cell subset phenotyping and signaling responses to cytokine stimulations on CD4+ and CD8+ T cells, B cells and monocytes, as well as the phosphorylation of PLC-γ and Akt upon BCR crosslinking on B cells. Serum samples from d0 and d28 are utilized for determination of anti-influenza antibody titers by the HAI assay. Measurements from d0 are processed and subjected to computational modeling for prediction of the antibody response.