CD40LG and influenza: Surprisingly, influenza-specific IGHM sequences showed an increased nucleotide diversity from germline along the IGHV gene region in vaccinated foals when compared to non-vaccinated foals, suggesting a greater emphasis in IGHM mutations using the influenza vaccine product; curiously, other studies have shown that memory IgM B cells harbor more mutations than naïve IgM B cells [64–66].