To provide additional confirmation of oral polymicrobial infection and to document a bacterial specific humoral response to polymicrobial infection, we evaluated pathogen-specific serum IgG and IgM levels against formalin-killed whole cells for P. gingivalis, T. denticola, and T. forsythia in mice sera from both polymicrobial-infected and sham-infected mice (Figure 2A). Here, CD40LG is linked to infection.