Furthermore, it was noted that the serum concentrations of both the IgM and IgG isotypes decreased 24 h post-myocardial infarction while the IgA isotype concentration remained stable, a difference thought to represent serum IgA’s inability to activate complement, form MAA-adduct immune complexes, or be cleared from circulation18. This evidence concerns the gene CD40LG and myocardial infarction.