Although 2-γ+ CD4 T cells could be terminally-differentiated, exhausted Th1 cells [26]–[28], sorted anti-influenza 2-γ+ cells, after restimulation, were able to express similar levels of IL-2 mRNA to the cells that were initially 2+γ+, suggesting that the 2-γ+ phenotype was more likely due to random expression patterns than exhausted Th1 cells. Here, CD4 is linked to influenza.