Refractory periodontitis associated with abnormal polymorphonuclear leukocyte phagocytosis and cigarette smoking.

To learn if refractory periodontitis may be associated with defects in peripheral blood polymorphonuclear leukocyte (PMN) function, phagocytosis and chemotaxis were analyzed in 31 otherwise healthy patients and 12 unaffected controls. When compared to controls, no chemotactic defects to 10 nM f-Met-Leu-Phe (fMLP) were detected. In contrast, phagocytosis was significantly impaired (P < 0.001). The mean rates of adhesion and ingestion of opsonized Staphylococcus aureus by PMNs were 7.1 +/- 1.7 (+/- SD) and 1.4 +/- 0.5 bacteria/100 PMNs/minute respectively for patients, and 11.0 +/- 2.4 and 3.1 +/- 0.6 for unaffected, healthy controls. While the quality of oral hygiene and access to dental care were high, a retrospective search for associated environmental variables showed that 90% (28 of 31) of the refractory patients were smokers. The frequency of smokers is particularly striking, since only 21% of adults in Minnesota use tobacco regularly. These data suggest that there is a strong association between a peripheral blood PMN defect and refractory periodontitis. Furthermore, these studies suggest that tobacco use may contribute to this association.

[Relationship between serum antibody to Bacteroides gingivalis and clinical parameters in periodontitis patients].

Prevalence and proportion of black-pigmented Bacteroides species (BPB) in supragingival and subgingival plaque were determined in ten adult periodontitis patients. Serum antibody against Bacteroides gingivalis (Bg) of these patients were tested using ELISA. Clinical parameters (PI, GI, PD, AL) were collected prior to blood withdrawn. Results showed that BPB were detected in all patients. Mean serum anti-Bg IgG level was significantly greater in the patient group than that in healthy control group. Although the sample size was too small to show statistical difference, there was a trend showing the sera anti-Bg IgG level tended to be greater in accordance with the increase of disease severity and BPB%.

Phenotypic characterization of Streptococcus sanguis virulence factors associated with bacterial endocarditis.

Certain strains of Streptococcus sanguis adhere (Adh+) selectively to human platelets and, in plasma, induce them to aggregate (Agg+) into in vitro thrombi. In this study, we examined 18 recent endocarditis and dental plaque isolates of microorganisms that were biotyped as S. sanguis for coexpression of platelet interactivity phenotypes with another possible virulence factor in bacterial endocarditis, dextran synthesis. Detectable production of extracellular glucosyltransferase ranged from 0.2 to 66 mU/mg of culture fluid for 10 representative strains tested. Production of extracellular or cell-associated glucosyltransferase, fructosyltransferase, and soluble or insoluble dextrans was not necessarily coexpressed with platelet interactivity phenotypes, since the levels of production of soluble and insoluble dextrans varied among representative Adh+ Agg+ and Adh- Agg- strains. Analysis of a second panel of 38 fresh dental plaque isolates showed that S. sanguis distributes in a reproducible manner into the possible phenotype groups. Strains with different platelet interactivity phenotypes were distinguished with a panel of four murine monoclonal antibodies (MAbs) raised against Adh+ Agg+ strain 133-79 and screened to rule out artifactual reactions with antigenic components in culture media. The MAbs reacted selectively with Adh+ Agg+ strains in a direct-binding, whole-cell, enzyme-linked immunosorbent assay and also inhibited their interactions with platelets. Analysis of minimal tryptic digests of many strains, including variants that failed to bind the MAbs, suggested that some noninteractivity phenotypes possess cryptic surface determinants. Since the ability to adhere to platelets and induce them to aggregate is relatively stable, these traits may be useful in a phenotyping scheme for these Lancefield nontypeable streptococci.