Significance of serum antibody against surface antigens of Actinobacillus actinomycetemcomitans in patients with adult periodontitis

Abstract

This study was undertaken to examine the prevalence of Actinobacillus actinomycetemcomitans, its serotype distribution and the serum immune responses against its surface antigens in 41 Japanese patients with adult periodontitis. The dominant A. actinomycetemcomitans serotype isolated was serotype c. Immunoblot analysis of 3 serotypes of A. actinomycetemcomitans-sonicated antigens and the patient sera revealed that the reactivities with serotype c were the most frequent and that heat-stable surface serotype-specific antigen appeared to be immunodominant. Elevated serum immunoglobulin G titers to extracted lipopolysaccharide and fimbriae antigen of A. actinomycetemcomitans were noted for the patient sera by enzyme-linked immunosorbent assay. High serum immunoglobulin G titers to the fimbriae antigen detected in patients without cultivable A. actinomycetemcomitans suggested the possibility that the elicited antibody to the antigen played a role in eliminating A. actinomycetemcomitans from the periodontal lesions.

Monoclonal Antibodies That Bind to Common Epitopes on the Dengue Virus Type 2 Nonstructural-1 and Envelope Glycoproteins Display Weak Neutralizing Activity and Differentiated Responses to Virulent Strains: Implications for Pathogenesis and Vaccines

“…After being washed with phosphate-buffered saline (PBS) (pH 7.4), the plates were blocked for 2 h at 25°C with 1% (wt/vol) gelatin (Sigma) in PBS (100 g/well). After being washed with PBS containing 0.05% Tween 20 (Sigma) (PBS/T), triplicate serial three-or fourfold dilutions of each MAb were prepared in PBS/T containing 0.25% (wt/vol) gelatin (PBS/T/G), with and without 10 mM DEA (Sigma; pH 11.0) (triplicate titrations with and without DEA), to gauge their avidity (33). After incubation at 25°C for 2 h, the contents of each well were aspirated.…”

“…The abilities of six MAbs generated to the DENV-2 NS1 glycoprotein to cross-react with purified DENV-2 particles in an ELISA in the presence and absence of DEA were tested to gauge their relative avidities (33). In this study, all of the MAbs generated to the DENV-2 NS1 glycoprotein had moderately high to high ELISA titers against the homologous DENV-2 NS1 glycoprotein (1/log 10 t 50 , 4.52 to 6.12) ( Table 1).…”

Elevated serum IgG titer and avidity to Actinobacillus actinomycetemcomitans serotype c in Japanese periodontitis patients

“…Previous studies reported variations in the distribution of A. actinomycetemcomitans serotypes in different geographic/ethnic populations (4, 8, 27, 34, 35, 45). A recent report from Switzerland (16) demonstrated broad serotype diversity in a young ethnographically heterogeneous periodontitis group.…”

“…Serotype b strains were frequently isolated from localized juvenile periodontitis patients in the United States (46) and in Finnish (4) subjects with periodontal disease. A predominance of serotypes other than b, however, has been reported from other parts of the world (8, 34, 35). Chung et al.…”

“…Saito et al. (36) demonstrated that high‐titer sera from patients without cultivable A. actinomycetemcomitans had higher avidity than sera from patients with high antibody titers and cultivable A. actinomycetemcomitans . These results suggest that high avidity antibody to A. actinomycetemcomitans may afford protection against A. actinomycetemcomitans infection.…”