Serum antibody responses to indigenous oral mucosal antigens and selected laboratory-maintained bacteria in recurrent aphthous ulceration.

Sera from subjects with recurrent aphthous ulceration (RAU) and control subjects were tested for relative levels of IgM, IgG, and IgA antibodies against eight selected laboratory-maintained bacteria, including Streptococcus sanguis which has been implicated in the etiopathogenesis of RAU. There were no differences in relative serum antibody levels for any isotype against any bacteria between control and RAU groups. RAU subjects with active lesions were then paired with control subjects, and each serum was tested against sedimentable material derived from the oral mucosa of each pair member. The analysis of data indicated that RAU and control subjects had similar levels of serum antibodies to indigenous mucosal antigens, but RAU subjects had significantly less antigenic material than control subjects.