CXCR5 and infection: As expected from the short interval spanning between infection and sample collection, the maternal frequency of B cells, class-switched IgD– B cells, CD4+ T cells, activated CD4+ T cells, CCR6+ T cells, and CXCR5+ T cells remained equivalent in the presence or absence of symptoms (Figure 3, A–F, and Supplemental Figure 3, A and B).