Figure 2

Influenza-specific CD4 ⁺ T-cell responses to vaccination in the immunogenicity cohort. Box and whisker plots describing the frequency of CD4⁺ T cells (A) specific for the three (pooled) influenza vaccine strains and identified as expressing two or more immune markers among CD40L, IL-2, TNF-α and IFN-γ after a short term in vitro stimulation; (B-left) specific for each of the individual influenza vaccine strains and induced to express at least two immune markers; and (B-right) specific for the three (pooled) influenza vaccine strains and induced to express one defined immune marker (x-axis) and at least one other. The whiskers extend to the lowest (Min) and highest (Max) values; the box extends to the 1st quartile (Q1) and 3rd quartiles (Q3) in which the median is marked by a horizontal line.