Evidence for local immunoglobulin synthesis in periodontitis

[Pathogenesis of parodontitis in rheumatic diseases]

Inflammatory periodontal disease (PD) is a common disease worldwide that has a primarily bacterial aetiology and is characterized by dysregulation of the host inflammatory response. The degree of inflammation varies among individuals with PD independently of the degree of bacterial infection, suggesting that alteration of the immune function may substantially contribute to its extent. Factors such as smoking, education, and body mass index (BMI) are discussed as potential risk factors for PD. Most PD patients respond to bacterial invaders by mobilizing their defensive cells and releasing cytokines such as interleukin (IL)-1beta, tumour necrosis factor (TNF)-alpha, and IL-6, which ultimately causes tissue destruction by stimulating the production of collagenolytic enzymes, such matrix metalloproteinases. Recently, there has been growing evidence suggesting an association between PD and the increased risk of systemic diseases, such ateriosclerosis, diabetes mellitus, stroke, and rheumatoid arthritis (RA). PD and rheumatologic diseases such as RA share many pathological aspects and immunological findings.

Specific antibodies against Actinobacillus actinomycetemcomitans in serum and saliva of patients with advanced periodontitis

The aim of the present study was to discover any possible correlation between specific antibodies against Actinobacillus actinomycetemcomitans (A.a.) in serum and saliva. The test group consisted of 38 patients aged 31-68 yr (mean 49) with advanced periodontitis. Twenty-nine subjects aged 23-67 yr, without periodontal destruction, formed a control group with a reference level of specific salivary antibodies against A.a. A subgingival plaque sample for culturing A.a., a specimen of stimulated whole saliva, and a sample of venous blood were taken from each subject of the test group. Specific IgG and IgA antibodies against A.a. were determined from serum and stimulated whole saliva by means of the ELISA test. Fifteen of the patients (39%) had cultivable A.a. Six of the 15 A.a. culture-positive patients and one of the 29 reference subjects exhibited very high antibody titers against A.a. in saliva. Specific IgG and IgA antibodies in saliva correlated highly significantly with the corresponding antibody values in serum among the patients in the test group. It was concluded that among patients with severe adult periodontitis, the less invasive saliva sample has a diagnostic value equal to that of the serum sample concerning specific antibodies against A.a.

Autoimmunity to collagen in adult periodontal disease: immunoglobulin classes in sera and tissue

The immunoglobulin class distribution of antibody to human collagen type I has been examined in sera and gingival extracts from patients with adult chronic periodontitis. Tissue extracts were made either by simple washing or ultrasonication. With either method, IgG and IgA antibodies to collagen were present in higher concentration in tissue extracts than in autologous serum when adjustment was made for dilution differences. No significant differences were found for IgM antibodies. Antibodies to human collagen type I are usually "natural antibodies" of the IgM class and, therefore, our findings suggest a class switch to IgG in inflamed gingivae, presumably due to prolonged antigenic stimulation.

IgG subclasses in gingival crevicular fluid from active versus stable periodontal sites

Since IgG subclasses are common immunoglobulins associated with the periodontium and have different biological characteristics, these subclasses were measured in gingival crevicular fluid (GCF) from periodontally active (greater than or equal to 2 mm clinical attachment loss within three months of sample) versus clinically similar but stable or healthy sites. A sandwich enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies was performed to quantitate IgG subclass and albumin concentrations in serum and interproximal GCF samples from at least one each of the three disease categories from each of 20 periodontal maintenance patients. Although much variability existed among sites, mean IgG1 (p less than 0.05) and IgG4 (p less than 0.01) concentrations were higher in GCF from active periodontitis areas than stable sites, even though both had similar clinical characteristics. When IgG subclass concentrations were adjusted per mg albumin, both IgG1 and IgG4 levels in GCF from active sites were still significantly elevated over stable areas (p less than 0.05). Mean adjusted concentrations in GCF were generally greater than in serum, especially for IgG4 (active site GCF:serum = 24.2:1). GCF IgG4 concentrations may be useful as an indicator of the immunopathological changes which occur in active periodontitis.

Salivary immunoglobulin concentrations in predentate and edentulous mouths

The concentrations of IgA, IgG and IgM in whole saliva of predentate babies, dentate adults, and edentulous old people, and the salivary IgG concentration of dentate old people, were determined using a solid phase radioimmunoassay. A highly significant difference in IgG concentrations was found between toothless and dentate people. The average IgG concentration in the saliva of edentulous old people was 5.2 mg/1, which was about 20% of that of dentate old people. The salivary IgG content of babies was only 1.7 mg/1, which was in concordance with the low postnatal serum IgG values. The salivary IgA level in this age group was also low. The edentulous old people tended to have decreased IgM values, and the predentate babies tended to have increased IgM values compared with the dentate adults.

Juvenile periodontitis. I. Demonstration of local immunoglobulin synthesis

The purpose of this investigation was to determine the presence and quantity of immunoglobulin G (IgG) and albumin (ALB) in specified periodontal tissues and serum from patients diagnosed as having juvenile periodontitis (JP), using an immunoelectrophoresis technique and to determine which portion of the lesion generated the greatest local immunoglobulin production. Serum and tissue samples were obtained from 19 patients (ages 13-21 years) who were diagnosed as having JP; 18 were female; 16 were black. Normal, diseased, and granulomatous gingival/periodontal tissues were collected during full thickness flap surgery, then minced, homogenized, and centrifuged. Supernatants containing the gingival/periodontal protein and the serum were electrophoresed against rabbit antihuman IgG and ALB. The relative IgG/ALB ratios in each specimen were plotted against known concentrations of IgG using a least squares analysis to provide evidence for local synthesis. In comparing mean IgG/ALB ratios for all tissue types, it was noted that normal gingiva did not differ significantly from serum. Diseased and granulomatous tissues, taken together or separately, had significantly higher IgG/ALB ratios than normal gingiva or serum, demonstrating that 73.6% of the IgG present was due to local synthesis. However, the greatest amounts of locally produced IgG were found in the granulomatous tissue from the deepest areas of the defects.

Local immunoglobulin synthesis in juvenile periodontitis: initial findings

An electro-immunoassay technique was used to determine simultaneously immunoglobulin G (IgG) and albumin concentrations in serum and extracts of gingival tissue comprising the pocket wall. Assays of samples obtained from seven patients with juvenile periodontitis (mean age, 18 years) indicated that local synthesis accounted for 72% of the IgG found in the gingiva.

Polyclonal activation of human peripheral blood B lymphocytes by Fusobacterium nucleatum

The present study examined in vitro polyclonal human B-lymphocyte (B-cell) activation (PBA) by Fusobacterium nucleatum. Pokeweed mitogen, a well-studied PBA activator, was included in some experiments for comparison. PBA was determined by the total immunoglobulin A, G, and M concentrations in the culture supernatants as measured by micro-enzyme-linked immunosorbent assay. F. nucleatum, at concentrations between 1 and 10 micrograms/ml, stimulated optimal PBA in monocyte-depleted cultures, whereas the pokeweed mitogen response was optimal in unfractionated, monocyte-containing cultures. Immunoglobulin synthesis occurred primarily between days 6 and 8 after stimulation with F. nucleatum. T lymphocytes enhanced the PBA response to F. nucleatum, particularly at a T- to B-cell ratio of 1:1. Immunoglobulin production was greater in round-bottomed wells than in flat-bottomed wells at lymphocyte concentrations of 200,000 cells per well. The PBA response, however, increased dramatically in flat-bottomed wells containing higher lymphocyte concentrations, suggesting that PBA is enhanced by cell-to-cell contact. A delay in stimulation of the lymphocytes with F. nucleatum resulted in diminished immunoglobulin production. The results provide information on the regulation of in vitro PBA induced by F. nucleatum. The data also suggest that there may be differences in the mechanisms by which F. nucleatum and pokeweed mitogen stimulate PBA.