Staining of skin sections with anti-IFN-γ antibodies confirmed the presence of IFN-γ-producing cells during the acute phase of infection (Fig. 2A,B), with both endogenous CD4+ and CD8+ (Fig. S2C,D), as well as transgenic gBT-I and gDT-II TEFF cells (Fig. 2C,D) contributing to this response. Here, CD4 is linked to infection.