Microflora in oral ecosystems in primary Sjögren's syndrome

OBJECTIVE

Knowledge of the effect of primary Sjögren's syndrome (pSS) on the microbial flora in the different predilection sites for oral disorders is needed for planning preventive treatment. We carried out microbial analysis of samples from the dorsum of the tongue, smooth mucosa, supragingival tooth surfaces, and the gingival crevice region of 20 patients with pSS.

METHODS

A clinical oral examination was performed and whole unstimulated and stimulated secretion rates were measured.

RESULTS

Compared with healthy controls, subjects with pSS harbored higher numbers and frequencies of Streptococcus mutans, Lactobacillus spp., and Candida albicans in the supragingival plaque. On the smooth mucosa and tongue, the pSS subjects displayed an increased frequency of C. albicans, Staphylococcus aureus, enterics, and enterococci. C. albicans was detected about twice as frequently in the supragingival plaque as it was on the tongue. In the gingival crevice region, the pSS group harbored slightly lower proportions of Fusobacterium nucleatum and Prevotella intermedia/Prevotella nigrescens than controls. The clinical and microbial differences were mainly due to the pSS subjects with a stimulated secretion rate of < 0.5 ml/min. Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans were not detected in any subject with pSS.

CONCLUSION

The microbial flora in the different ecosystems reflected the status of oral disorders in the subjects with pSS. Specific site sampling and analysis in subjects with pSS revealed further differences compared with controls, and is therefore preferable to saliva sampling for oral treatment planning and for the evaluation of the effect of oral treatment and of preventive measures implemented in individuals with pSS.

Ro/SS-A-reactive B lymphocytes in salivary glands and peripheral blood of patients with Sjögren's syndrome

The aim of this study was to investigate the production of anti-Ro/SS-A antibodies in labial salivary glands (LSG) and peripheral blood (PB) of Sjögren's syndrome (SS) patients. The ELISPOT method was performed to quantify the frequency of LSG lymphocytes and PB lymphocytes spontaneously secreting anti-Ro/SS-A antibodies. The total number of IgG-, IgA- and IgM-producing cells was also quantified. The bovine Ro 60-kD protein was used as target antigen. Six of six primary SS patients had LSG B cells producing anti-bovine Ro 60 kD of the IgG isotype, and two of two primary SS patients had in addition PB lymphocytes producing anti-bovine Ro 60 kD of the IgG isotype. The six patients who had IgG antibodies against the Ro/SS-A antigen in LSG all had focus scores of >/= 7 in biopsies of LSG. The results indicate that SS patients with a high degree of local inflammation in LSG have B cells producing anti-Ro/SS-A antibodies in both LSG and PB. Thus, the anti-Ro/SS-A antibodies may have pathogenic importance in the progression of the exocrinopathy of SS.

Oral microbial flora in Sjögren's syndrome

OBJECTIVE

To study presence of microorganisms associated with caries, gingivitis, oral opportunistic infections, and extent of hyposalivation in dentate patients with primary and secondary Sjögren's syndrome (SS).

METHODS

An oral clinical examination was performed. The salivary flow was measured and a rinsing sample analyzed for presence of specific microorganisms. The results were compared to those of healthy controls matched for sex, age, and number of teeth.

RESULTS

In patients with undetectable salivary flow at rest, mean number and proportion of mutans streptococci and lactobacilli showed a tendency to be increased, as well as the frequency of Candida. They also displayed an increased proportion of filled surfaces. In contrast, gingivitis and the numbers of microorganisms associated with gingivitis were comparable to those found in the healthy controls.

CONCLUSION

Patients with SS and severe hyposalivation harbor oral flora associated with the development of caries and frequent presence of retention sites, indicating a need for efficient preventive dental care.

Expression of the mucosal lymphocyte integrin alphaEbeta7 and its ligand E-cadherin in salivary glands of patients with Sjögren's syndrome

The expression of the mucosal lymphocyte integrin alphaEbeta7 and its ligand E-cadherin was analyzed in sialadenitic lesions of patients with Sjögren's syndrome in order to assess the potential interactions between the mucosal and the systemic immunological compartments. Immunohistochemical evaluation of the inflammatory infiltrates in the salivary gland tissues in Sjögren's syndrome patients revealed presence of alphaEbeta7-integrin-expressing lymphocytes, in 18 of 20 biopsies examined. The ligand for alphaEbeta7, E-cadherin was also found in 18 of 20 salivary gland biopsies analysed. These results suggest homing of lymphocytes derived from the gut epithelium through the blood stream to inflamed salivary gland tissue followed by in situ interaction with E-cadherin expressing cells, the ligand for alphaEbeta7 expressing T lymphocytes.

Differential immunological aberrations in patients with primary and secondary Sjögren's syndrome

The aim of the present study was to analyse possible differences in immunological features between patients with primary and secondary Sjögren's syndrome (SS). Ten patients with primary SS and 10 patients with secondary SS also suffering from rheumatoid arthritis, were identified according to established criteria for SS. Ten healthy, age-matched women served as controls. The authors analysed the phenotypic characteristics of lymphocytes in peripheral blood as well as in focal inflammatory infiltrates of minor salivary gland biopsies. Functional analyses of T lymphocytes were performed after stimulation with mitogens and antigen. B cell activity was determined at the single cell level by spontaneous and mitogen induced immunoglobulin production. Serum levels of IL-4, IL-6 and IFN-gamma were also analysed. Patients with primary SS displayed a significantly higher degree of salivary gland inflammation and reduced salivary flow than did patients with secondary SS. Decreased in vitro T cell responses to antigen and mitogens were evident in both patient groups. The CD4/CD8 ratios in both peripheral blood and salivary gland lesions were significantly lower in primary SS compared with secondary SS patients. Polyclonal B cell activation, measured as the frequency of spontaneous immunoglobulin producing cells, was most prominent in primary SS, whereas a diminished response to poke-weed mitogen (PWM), a T cell dependent B cell mitogen, was more pronounced in secondary SS. The results reveal certain immunological aberrations in the whole group of patients with SS. In addition, the authors demonstrated distinct differences in immune dysfunction between patients with primary and secondary SS, indicating that they may constitute separate entities.

Progression of sialadenitis in Sjögren's syndrome

An analysis of progression of sialadenitis in patients with primary and secondary SS has been performed. For this purpose patients were prospectively followed and evaluated with respect to stimulated whole salivary secretion and morphology of labial salivary gland biopsies. Twenty-one patients with primary SS and 18 with secondary SS were followed for a mean of 39 +/- 20 months (range 11-112 months). During this observation period the lymphocytic infiltration in minor salivary glands, measured as focus score, increased in 14/21 (67%) patients with primary SS and in 14/18 (78%) patients with secondary SS. Altogether there was a statistically significant increase in focus score in both primary and secondary SS, but no reduction in salivary production. Consequently, no correlation between changes in focus score and stimulated salivary secretion was found in either primary or secondary SS.

Surface membrane glycoproteins of macrophage-like synovial cells from rheumatoid and control patients

Synovial cells were prepared by enzyme digestion and Percoll gradient centrifugation of rheumatoid arthritis (RA) synovial specimens or by trypsin-rinsing of non-inflammatory cadaver joints. Most (70-80%) of the cells from RA patients were OKIa -positive macrophage-like cells, 10-20% other OKIa -positive cells, and about 10% fibroblastic cells, whereas 90% of the normal synovial cells were OKIa -positive macrophage-like cells and the rest fibroblasts. These adherent synovial cells were compared with fibroblastic synovial cells obtained by sequential passaging of explanted dividing cells. Periodate-[3H]borohydride labelling followed by SDS-gradient gel electrophoresis demonstrated similar sialo-glycoprotein patterns in both the adherent synovial cells and synovial fibroblasts. The molecular weights of the main surface glycoproteins resembled closely those of skin fibroblasts but not those of peripheral blood monocytes. RA samples showed inconsistent heterogeneity. The results indicate either that all synovial cells possess a similar basic structure or that macrophages of peripheral blood origin express fibroblastic contact glycoproteins when settling down into synovium.