CD4 and influenza: Influenza-induced IL-2+/TNF-α+(IFN-γ−) CD4+ T cells have been described as uncommitted Th1 Thpp preferentially promoted by recent, pandemic epitopes whereas common, multiply-boosted influenza epitope-specific CD4+ T cells expressed IFN-γ after influenza infections.32,33 Thpp have been proposed to serve as a reservoir of memory CD4+ T cells with effector potential.33 Our study further revealed that pre-boost Thpp response correlated with post-boost serological response enlightening the potential link between this particular T cells population and the B cell response.