This was not due to a generalized loss of Tfh cells in infected mice, since abundant CXCR5+ T cells were observed in the bulk (non-tetramer-binding) T cell population (Figure 4—figure supplement 1) and our previous study found strong Tfh polarization of GP66-specific CD4+ T cells at similar timepoints after infection with GP66-expressing parasites (Arroyo and Pepper, 2020). This evidence concerns the gene CD4 and infection.