CD19 and Salmonella Infections: Graded expression of T-bet in CCR6-RORγt+ ILCs facilitates the differentiation of IFNγ-producing CCR6-RORγt+ ILCs required to protect the epithelial barrier against Salmonella infections (Klose et al., 2013), implying that T-bet is indispensable for the functional plasticity of some groups in CD3-CD19- cell subsets against pathogens.