IL4 and infection: Consistent with the above findings, infection of BALB/c WT mice with VV-HA-IL-4 compared to VV-HA control infection significantly reduced the numbers of IFN-γ+ and IFN-γ+ TNF-α+ KdA5275–83 or KdF226–34 specific-CD8+ T cells (figure 8A and 8C).