While Ramos et al. found less WNV-specific effector CD8+ T cells (i.e. producing TNF, IFN-γ, perforin and granzyme) in infected IL-1R1−/− mice, Durrant et al. could only link impaired effector CD4+ T cells responses to IL-1R1 deficiency during infection (237–239). The gene discussed is IFNG; the disease is infection.