However, since Pape et al. 28 demonstrated that IgM+ IgD+ MBCs in the PE/CFA immunization system dominantly comprised those possessing fewer SHMs, IgM+ IgD+ MBCs likely expressed few SHMs, and the discrepancy may be explained in terms of antigens employed, namely, NP, PE or malaria. Here, CD40LG is linked to malaria.