CD4 and malaria: Although ifnar1-/- CD4 T cells did not expand or accumulate to the same degree as WT CD4 T cells (S5A and S5B Fig) we found no difference in the proportion of WT and ifnar1-/- donor-derived cells that adopted the canonical CXCR5+PD-1hiBcl-6+ Tfh phenotype (S5A–S5D Fig), suggesting that direct IFNAR signaling on CD4 T cells does not intrinsically impair Tfh differentiation during experimental malaria.