leukotoxin and Gingival-Hemorrhage

Cross-sectional and longitudinal studies identify the JP2 clone of Aggregatibacter actinomycetemcomitans as an aetiological agent of aggressive periodontitis (AgP) in adolescents of northwest African descent. To gain information on why a significant part of Moroccan adolescents show clinical signs of periodontal disease in the absence of this pathogen we performed comprehensive mapping of the subgingival microbiota of eight young Moroccans, four of whom were diagnosed with clinical signs of AgP. The analysis was carried out by sequencing and phylogenetic analysis of a total of 2717 cloned polymerase chain reaction amplicons of the phylogenetically informative 16S ribosomal RNA gene. The analyses revealed a total of 173 bacterial taxa of which 39% were previously undetected. The JP2 clone constituted a minor proportion of the complex subgingival microbiota in patients with active disease. Rather than identifying alternative aetiologies to AgP, the recorded infection history of the subjects combined with remarkably high concentrations of antibodies against the A. actinomycetemcomitans leukotoxin suggest that disease activity was terminated in some patients with AgP as a result of elimination of the JP2 clone. This study provides information on the microbial context of the JP2 clone activity in a JP2-susceptible population and suggests that such individuals may develop immunity to AgP.

Topics: Actinobacillus Infections; Adolescent; Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Antibodies, Bacterial; Bacterial Toxins; Case-Control Studies; Clone Cells; Disease Susceptibility; Exotoxins; Gingival Hemorrhage; Humans; Immunosuppressive Agents; Morocco; Nucleic Acid Amplification Techniques; Periodontal Attachment Loss; Periodontal Pocket; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Young Adult

The identification of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) serotypes may add some important information to the understanding of the pathogenetic background of severe periodontal infections. This study compared serotypes of A. actinomycetemcomitans in two groups of periodontal patients with different ethnic backgrounds.. A total of 194 patients (96 Germans and 98 Koreans) with aggressive or severe chronic periodontitis participated in the study. Microbiologic analysis of pooled samples from subgingival plaque was performed by using a real-time polymerase chain reaction (PCR) test for A. actinomycetemcomitans. In patients who tested positive for A. actinomycetemcomitans, serotypes (a through f) were determined by nucleic acid-based methods.. The prevalence of patients who tested positive for A. actinomycetemcomitans with the real-time PCR was comparable in both groups (Germans: 27.0%; Koreans: 22.2%). In German patients, the serotypes detected most frequently were b (33.3%), c (25.0%), and a (20.8%), whereas in Korean patients, the serotype distribution was different, with serotypes c (61.9%) and d (19.0%) accounting for >80% of the complete serotype spectrum.. Even if the percentage of patients who tested positive for A. actinomycetemcomitans was identical in patients with generalized aggressive and severe chronic periodontitis and different ethnic backgrounds, the distribution of A. actinomycetemcomitans serotypes may exhibit marked differences.

Topics: Actinobacillus Infections; Adult; Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Asian People; Bacterial Toxins; Chronic Periodontitis; Dental Plaque; Dental Plaque Index; Ethnicity; Exotoxins; Female; Germany; Gingival Hemorrhage; Humans; Korea; Male; Middle Aged; Operon; Periodontal Attachment Loss; Periodontal Index; Periodontal Pocket; Polymerase Chain Reaction; Promoter Regions, Genetic; Serotyping; White People

beta2-Glycoprotein I (beta 2GPI) is important in the suppression of coagulation, and antibodies against TLRVYK peptides on the beta 2GPI molecule are related to thrombosis. According to the Swiss-Prot database, Aggregatibacter actinomycetemcomitans leukotoxin c has sequences (SIRVYK) that are homologous to the TLRVYK peptides. The aim of this study was to investigate the effects of A. actinomycetemcomitans infection on the antibody response against SIRVYK peptides in patients with periodontitis.. Serum immunoglobulin G (IgG) antibody and IgG subclass antibody titers against SIRVYK or TLRVYK peptides were measured by enzyme-linked immunosorbent assay in 46 patients with aggressive periodontitis (eight with localized disease, 38 with generalized disease), 28 patients with chronic periodontitis, and 20 periodontally healthy subjects. The presence of A. actinomycetemcomitans in plaque and saliva samples was determined using polymerase chain reaction.. The level of anti-SIRVYK antibodies was significantly higher in patients who were A. actinomycetemcomitans-positive than in A. actinomycetemcomitans-negative patients (P < 0.05) in the chronic periodontitis group. A similar trend was found in the antibody response to TLRVYK peptide; however, no statistically significant difference was seen between A. actinomycetemcomitans-positive and -negative patients. The A. actinomycetemcomitans-positive patients displayed significantly higher levels of anti-SIRVYK IgG2 and IgG3 antibodies than A. actinomycetemcomitans-negative patients (P < 0.05 and P < 0.05, respectively). The level of IgG2 was highest among the four IgG subclasses and it predominantly increased in patients who were A. actinomycetemcomitans-positive. Anti-TLRVYK antibody levels were significantly correlated with anti-SIRVYK IgG antibody levels.. The results suggest that A. actinomycetemcomitans infection may elicit anti-SIRVYK IgG antibodies and modify the anti-TLRVYK antibody response in patients with periodontitis by molecular mimicry with beta2GPI.

Topics: Adult; Aggregatibacter actinomycetemcomitans; Antibodies, Bacterial; Anticoagulants; Bacterial Toxins; beta 2-Glycoprotein I; Chronic Disease; Dental Plaque; Exotoxins; Gingival Hemorrhage; Humans; Immunoglobulin G; Middle Aged; Molecular Mimicry; Peptide Fragments; Periodontal Pocket; Periodontitis; Periodontium; Polymerase Chain Reaction; Saliva

The aim of the present study was to investigate the intraoral distribution of Actinobacillus actinomycetemcomitans in young adults with minor signs of periodontal disease but harboring the organisms in the oral cavity. 17 healthy volunteers, 20 to 27 years of age, participated. Samples from mucosal surfaces of the oro-pharyngeal cavity and saliva (n = 221) as well as subgingival plaque from every tooth (n =477) were selectively cultivated for A. actinomycetemcomitans. Species identity and presence of the leukotoxin encoding gene, ltxA, were checked by multiplex polymerase chain reaction. Moreover, the leukotoxin promoter region was analyzed. No isolate harbored a 530 bp deletion in the promoter region of the leukotoxin gene, signaling minimally toxic strains. 42.1 +/- 30.4% extracrevicular and 34.4 +/- 29.5% subgingival samples were culture-positive. In extracrevicular samples, the organism could easily be recovered from cheek mucosa (62%), saliva (59%) and the palatal tonsils (41%). Mean log-transformed numbers of A. actinomycetecomitans colony forming units (CFU/ml) in culture-positive material ranged between 1.8 from the hard palate and 2.3 from 10 microl saliva. The highest prevalence in subgingival plaque was observed at maxillary 3rd molars (55%) followed by maxillary lateral incisors (50%) and mandibular 3rd molars (41%). Mean log-transformed counts of CFU/ml ranged between 2.2 at maxillary 3rd molars and 3.4 at upper central incisors. When adjusted for jaw, site and tooth type, the odds of isolating higher numbers of the organism were increased with every mm probing depth by a factor of 1.35 (p <0.05). The odds ratio for bleeding on probing was 1.38. Thus, in this young adult population with minor periodontal disease, A. actinomyetemcomitans was mainly associated with some deviation from gingival health. Of concern might be a minority of subjects (29%) with an extremely wide distribution of the organism in the oral cavity.

Topics: Adolescent; Adult; Aggregatibacter actinomycetemcomitans; Bacterial Toxins; Base Pairing; Colony Count, Microbial; Dental Plaque; Exotoxins; Female; Gingiva; Gingival Hemorrhage; Humans; Incisor; Male; Molar, Third; Mouth; Mouth Mucosa; Odds Ratio; Oropharynx; Palatine Tonsil; Periodontal Diseases; Polymerase Chain Reaction; Prevalence; Promoter Regions, Genetic; Saliva; Sequence Deletion; Statistics as Topic; Tongue

Eighteen (18) members of an extended family in which numerous individuals have Papillon-Lefèvre syndrome (PLS) were examined. In all, 6 affected members and 12 non-affected members were included. All patients underwent a clinical examination which, in the dentate persons, included plaque index, bleeding on probing, probing depth, and periodontal attachment loss and a set of full mouth periapical x-rays. Subgingival bacterial samples were also collected from 2 teeth in the dentate patients for cultures and identification of Actinobacillus actinomycetemcomitans. Serum samples were collected from all participants and assayed for antileukotoxin antibodies. The results indicate that there is a high prevalence of leukotoxic strains of A. actinomycetemcomitans in persons suffering from PLS, as well as in unaffected family members. The ubiquitous presence of A. actinomycetemcomitans in the family units suggests a close association between A. actinomycetemcomitans and the periodontal disease associated with the syndrome; it also suggests that A. actinomycetemcomitans by itself is not sufficient for the expression of periodontal disease and that other factors, some of which must be genetic, are necessary for lesion development.

Topics: Adolescent; Adult; Aggregatibacter actinomycetemcomitans; Antibodies, Bacterial; Bacteria; Bacterial Toxins; Child, Preschool; Colony Count, Microbial; Cytotoxins; Dental Plaque Index; Exotoxins; Female; Gingival Hemorrhage; Humans; Male; Middle Aged; Papillon-Lefevre Disease; Periodontal Attachment Loss; Periodontal Diseases; Periodontal Pocket

In a previous population-based study of 3896 7-9-year-old children living in Sweden, it was found that 32 children (0.8%) exhibited radiographic, periodontal bone loss at > or = 2 proximal surfaces of their deciduous teeth. In the present study, 26 of the 32 children were subjected to additional oral and systemic health examination. 20 other children without any radiographic evidence of bone loss in their primary dentition served as referents. None of the cases or the referents were detected to have any systemic disease. The frequency of bleeding and suppuration on probing, radiographic proximal calculus and probing attachment loss was higher among the cases than the referents. Actinobacillus actinomycetemcomitants was found subgingivally in 14 of the cases but in none of the referents. 11 of 22 cases analysed for presence of serum antibodies against A. actinomycetemcomitans leukotoxin were sero-positive compared to none of 7 referents available for analysis. Evaluation of the data from each child revealed wide variations in clinical parameters among the children in the case group. In this group, there were children with deep probing depths, probing attachment loss, suppuration on probing, proximal calculus and presence of subgingival A. actinomycetemcomitans, indicating current periodontitis. However, in the case group there were also children without positive signs of inflammatory disease, similar to the children in the reference group. In fact, the findings suggest that less than half of the number of individuals with > or = 2 proximal sites with bone loss had current periodontitis.

Topics: Aggregatibacter actinomycetemcomitans; Alveolar Bone Loss; Antibodies, Bacterial; Bacterial Toxins; Case-Control Studies; Child; Dental Calculus; Dental Plaque; Exotoxins; Female; Gingival Hemorrhage; Health Status; Humans; Male; Periodontal Attachment Loss; Periodontal Pocket; Periodontitis; Suppuration; Tooth, Deciduous