Abstract
Serum IgG1, IgG2, IgG3 and IgG4 antibody levels directed against lipopolysaccharides (LPS) from Bacteroides gingivalis were measured in the sera from systemically healthy subjects with and without periodontitis. An enzyme-linked immunosorbent assay was used that included coating of microtiter plates with LPS, and subsequent incubation with patient sera followed by mouse monoclonal subclass-specific antibodies, biotinylated sheep anti-mouse IgG and alkaline phosphatase conjugated to streptavidin. Anti-LPS IgG antibodies were dominated by IgG2, and moderate amounts only of IgG1, IgG3 and IgG4 were found. The periodonitis patients had significantly higher anti-LPS IgG1, IgG2 and IgG3 levels when compared to the subjects with healthy periodontium (p < 0.05, Mann-Whitney test).