CD40LG and infection: Consistently, mouse malaria studies found that IgM+ MBCs adopt a GC B‐cell phenotype upon secondary infection (Pietrzak et al, 2020), while sequencing studies revealed that IgM+ MBCs acquire further mutations upon P. falciparum re‐infection in children (Wendel et al, 2017), suggesting a role for unswitched MBCs in B‐cell receptor repertoire expansion and remodeling during malaria.