A study of the localized humoral immune response to implicated microorganisms in juvenile periodontitis

A study was undertaken using an in vitro explant culture system to determine the presence of immunoglobulins (IgG, IgA, and IgM) in the supernatant fluids (SF) of disease gingival tissue explant cultures. Studies were also undertaken to determine if the de novo biosynthesis of 14C-immunoglobulins could be observed in the explant cultures of diseased tissues from juvenile periodontitis (JP) patients. Radiolabeled proteins were detected in the SF and immunodiffusion studies using goat antihuman gamma, alpha or mu chain serum revealed the presence of IgG and IgA but no IgM present in the SF of the JP gingival tissue explant cultures. Immunodiffusion studies using goat anti-human gamma chain serum with Staph protein A isolated IgG fractions of the SF, followed by autoradiography of the IgG precipitation lines demonstrated the biosynthesis of IgG by the JP gingival tissue explant cultures. The serological studies suggested that local immune response in JP was to a polymicrobic infection. The SF of JP showed significantly higher levels of antibody reactivity to B. intermedius, C. ochracea, E. nodatum and P. micros as compared to healthy tissues. The local antibody response to the microorganisms tested differed from that observed in the sera of the patients