Association of patterns of labial salivary gland inflammation with keratoconjunctivitis sicca. Analysis of 618 patients with suspected Sjögren's syndrome

Apoptosis and estrogen deficiency in primary Sjögren syndrome

PURPOSE OF REVIEW

Primary Sjögren syndrome is an autoimmune disorder characterized by lymphocytic infiltrates and destruction of the salivary and lacrimal glands, and systemic production of autoantibodies to the ribonucleoprotein particles SS-A/Ro and SS-B/La. The purpose of this review is to discuss recent advances in the pathogenesis of primary Sjögren syndrome.

RECENT FINDINGS

Although several candidate autoantigens including alpha-fodrin have been reported in Sjögren syndrome, the pathogenic roles of the autoantigens in initiation and progression of SS are still unclear. It is possible that individual T cells activated by an appropriate self antigen can proliferate and form a restricted clone. Recent evidence suggests that the apoptotic pathway plays a central role in tolerizing T cells to tissue-specific self antigen, and may drive the autoimmune phenomenon. Cleavage of certain autoantigens during apoptosis may reveal immunocryptic epitopes that could potentially induce autoimmune response. The studies reviewed imply that Fas-mediated cytotoxicity and caspase-mediated alpha-fodrin proteolysis are involved in the progression of tissue destruction in Sjögren syndrome. Fas ligand (FasL), and its receptor Fas are essential in the homeostasis of the peripheral immune system. It can be considered that a defect in activation-induced cell death of effector T cells may result in the development of autoimmune exocrinopathy in Sjögren syndrome.

SUMMARY

Although the mechanisms by which estrogen deficiency influences autoimmune lesions remain unclear, it is possible that antiestrogenic actions might be a potent factor in the formation of pathogenic autoantigens.

A primary care approach to Sjögren's syndrome. Helping patients cope with sicca symptoms, extraglandular manifestations

Sjögren's syndrome is a chronic, systemic, autoimmune inflammatory disorder characterized by lymphocytic infiltration of exocrine glands, most notably the salivary and lacrimal glands. It results in loss of functional epithelium, diminished exocrine function, and gradual onset of dryness of the eyes, mouth, and other body parts (sicca syndrome). Because most patients with Sjögren's syndrome are female, this syndrome also represents a major women's health problem that is often misdiagnosed and undertreated. In this article, Drs Derk and Vivino review the criteria for diagnosis, common signs and symptoms, and strategies for increasing patient comfort.

Estrogen deficiency accelerates murine autoimmune arthritis associated with receptor activator of nuclear factor-kappa B ligand-mediated osteoclastogenesis

The aims of this study were to evaluate the in vivo effects of estrogen deficiency in MRL/lpr mice as a model for rheumatoid arthritis and to analyze the possible relationship between immune dysregulation and receptor activator of nuclear factor-kappaB ligand (RANKL)-mediated osteoclastogenesis. Experimental studies were performed in ovariectomized (Ovx)-MRL/lpr, Ovx-MRL+/+, sham-operated-MRL/lpr, and sham-operated-MRL+/+ mice. Severe autoimmune arthritis developed in younger Ovx-MRL/lpr mice until 24 wk of age, whereas these lesions were entirely recovered by pharmacological levels of estrogen administration. A significant elevation in serum rheumatoid factor, anti-double-stranded DNA, and anti-type II collagen was found in Ovx-MRL/lpr mice and recovered in mice that underwent estrogen administration. A high proportion of CD4(+) T cells bearing RANKL was found, and an enhanced expression of RANKL mRNA and an impaired osteoprotegerin mRNA was detected in the synovium. An increase in both osteoclast formation and bone resorption pits was found. These results indicate that estrogen deficiency may play a crucial role in acceleration of autoimmune arthritis associated with RANKL-mediated osteoclastogenesis in a murine model for rheumatoid arthritis.

Hyperprolactinemia in Sjogren’s syndrome: a patient subset or a disease manifestation?

OBJECTIVE

To investigate the prevalence of hyperprolactinemia in patients with primary Sjogren's syndrome (SS), its clinical significance and its implication to our understanding of the disease pathogenesis.

MATERIALS AND METHODS

Forty-nine patients with primary SS (44 females and five males) age range 37-66 years were included in this study. All patients underwent clinical assessment for disease manifestations in addition to laboratory assessment for serum prolactin, sex hormones and immunological profile. Fifty healthy subjects (44 females and six males) of matched age were studied as control group.

RESULTS

The mean prolactin serum level was significantly higher in SS patients compared to the control group (P < 0.01). This significant difference was persistent after subgrouping the patients and the controls based on their menstrual history. Hyperprolactinemia (>20 ng/ml) was prevalent in 16.3% of SS patients. There was no correlation between serum prolactin levels and hormonal status, autoantibodies as well as systemic manifestations of the disease.

CONCLUSION

Patients with primary SS have moderately increased levels of prolactin. Hyperprolactinemia reflects disease pathology rather than being present in a subset of patients. The presence of elevated prolactin levels was not associated with hormonal status, clinical or immunological manifestations of primary SS.

The oral component of Sjögren's syndrome: pass the scalpel and check the water

The labial salivary gland biopsy is a diagnostic test for the oral component of Sjögren's syndrome (SS) that has been the subject of controversy and re-examination for many years. Despite multiple recent challenges to the significance of this test, when correctly done, it remains one of the most informative, specific, and technically simple tests available for the oral component of SS. Because of compromised salivary gland function, patients with SS are at risk for dental caries. Within the past decade, a paradigm shift has occurred within the field of caries research. The caries process was previously thought irreversible once initiated. Research has shown that the "early" carious lesion can be remineralized. Thus, the "early" carious lesion may be prevented and even repaired. The process of remineralization requires appropriate conditions to occur, and one of those conditions is pH. Because water is often the preferred wetting agent/beverage for patients with SS, the data show that, with regard to pH, not all waters are created equal.

New concepts in the pathogenesis of Sjögren syndrome: many questions, fewer answers

Although a modified European-American consensus classification of Sjögren syndrome has been introduced during the last year, the etiopathogenesis of this disease characterized by chronic lymphocytic inflammation, impaired function, and, finally, destruction of the salivary and lacrimal glands as well as systemic manifestations remains to be elucidated. Recent insights into the pathogenesis of Sjögren syndrome resulting from immunogenetic, hormonal, and epidemiologic evaluations as well as animal and in vitro studies are highlighted by this review. Evidence confirms that lymphocytic disturbances, including ectopic germinal center formation and aberrations of cellular signaling play a significant role in Sjögren syndrome. Although some of these features are unique to Sjögren syndrome, others are also found in a number of systemic autoimmune diseases, such as systemic lupus erythematosus, systemic sclerosis, and rheumatoid arthritis. The underlying cause of Sjögren syndrome remains largely enigmatic. However, distinct characteristics may provide the basis for the classification of the disease entities. Finally, an enhanced risk of lymphomagenesis is a well-known hallmark of primary Sjögren syndrome, indicating the central role of derangement of lymphocyte regulation. As demonstrated by the introduction of the new targeted therapeutic approaches in rheumatoid arthritis, solid insights into the pathogenesis of Sjögren syndrome may pave the way toward new therapeutic approaches.

Primary Sjögren syndrome in childhood: report of a case and review of the literature

Sjögren syndrome (SS) in childhood is a rare and possibly underdiagnosed condition. The purpose of this study is to report a case of primary SS (PSS) in a 4-year-old Venezuelan girl and to review the pertinent literature. The patient presented with bilateral recurrent parotid enlargement, predominantly on the right side. She did not complain of dry mouth or eyes; however, decreased stimulated salivary flow rate and positive Schirmer and rose bengal tests were obtained. Sialography, sonograms, and a computed tomography scan of the parotid glands revealed pathologic changes consistent with SS. Anti-SS-A and anti-SS-B antibodies were present. Evaluation for antibodies against cytomegalovirus, Epstein-Barr virus, and HIV rendered negative results. Histopathologic examination of incisional biopsies of the right parotid and labial minor salivary glands revealed focal periductal lymphocytic infiltrate and sialoduct ectasia. Taken together, these findings are consistent with the diagnosis of juvenile PSS. The salient features of this rare disease are summarized on the basis of a comprehensive review of the epidemiologic, clinical, and serologic findings of the previously reported cases of PSS in children.

Periodontitis, caries and salivary factors in Sjögren's syndrome patients compared to sex- and age-matched controls

The aims of this investigation were: (i) to study a group of dry mouth Sjögren's syndrome (SS) patients comprising individuals with pathological and non-pathological amounts of rest saliva and (ii) to compare these two categories of SS patients with a sex- and age-matched control group with respect to their periodontal and dental status. Thirty-three dry mouth patients and 33 sex- and age-matched patients, referred to the same private dental clinic in southern Norway, were examined for rest and stimulated saliva, as well as their dental and periodontal status. All patients were referred to the local hospital for blood and urine examinations. The dry mouth SS patients were all of the secondary type. Volumes of rest and stimulated saliva were significantly lower in the low saliva SS group compared with the high saliva SS group; the values for immunoglobulin G (IgG) and IgA were similarly lower for the low saliva group, but not for IgM which was significantly higher. The two SS subgroups and their controls were compared for the volume of rest and stimulated saliva, which showed a statistically significant lower volumes for the low saliva SS group compared with the control group. None of the subgroups and their controls differed concerning filled or missing teeth, but the total SS group revealed significantly higher number of missing teeth. The periodontal and dental status did not show any statistically significant differences except for a few scattered higher periodontal level losses of attachment in the SS subgroups. The blood and urine analyses showed statistically significant higher values for sedimentation rate, white blood cell count and haemoglobin in the SS low saliva group compared with the control group while anti-streptolysin was lower. In the high saliva SS group only sedimentation rate and white cell count were higher compared with the control. The conclusions is SS patients do not have an increased risk for developing periodontitis.

Prevalence and clinical significance of lymphocytic foci in minor salivary glands of healthy volunteers

OBJECTIVE

To determine the prevalence and severity of focal lymphocytic sialadenitis in minor salivary glands of healthy, asymptomatic individuals, in whom Sjögren's syndrome (SS) has been excluded.

METHODS

Charts of 54 healthy volunteers who had salivary gland biopsies at the National Institutes of Health from January 1992 to August 1998 were reviewed. The healthy volunteers served as control subjects in various studies of salivary dysfunction. Significant medical conditions including SS were excluded. A biopsy with a focus score (FS) >1 was regarded as positive. Descriptive statistics were used to summarize the population's characteristics.

RESULTS

The frequency of focal lymphocytic infiltration in the healthy volunteers was about 15% (8 of 54). None of these individuals had subjective xerostomia or dry eyes. The positive FS ranged from 2 to 6. FS did not correlate with age, smoking, serologic findings, or salivary flow in these patients.

CONCLUSION

Lymphocytic infiltration in minor salivary glands is not uncommon among individuals without a history of salivary gland dysfunction. This finding is in agreement with the result of a previous autopsy survey study, indicating that focal sialadenitis may occur in the absence of SS.

Autoantibodies in primary Sjögren's syndrome: new insights into mechanisms of autoantibody diversification and disease pathogenesis

Characterisation of autoantibodies and their target autoantigens in primary Sjögren's syndrome (SS) is an important entry point for studying this common systemic autoimmune disease. Diversification of anti-Ro/La responses is believed to occur by a process of determinant spreading following initiation of an autoimmune response to one component, possibly 52-kD Ro (Ro52). Recent evidence supports the ER-resident chaperone Grp78 as a potential candidate in the initiation of an autoimmune response against Ro52, by binding to a Grp78 binding motif in the COOH-terminal region of Ro52. The subsequent diversification of the anti-Ro/La response is influenced by distinct HLA class II alleles. Anti-salivary duct autoantibodies have been revisited and shown to be mimicked by cross-reactive isoantibodies to AB blood group antigens. Identification of autoantibodies that act as antagonists at M3-muscarinic receptors represents an important advance. As well as contributing to the sicca symptoms, the functional effects of these autoantibodies may explain associated features of autonomic dysfunction in patients with SS. Anti-M3 receptor autoantibodies occur in both primary and secondary SS and allow Sjögren's syndrome to be viewed as a disorder of anti-receptor autoimmunity.

Classification criteria for Sjögren's syndrome: a revised version of the European criteria proposed by the American-European Consensus Group

Classification criteria for Sjögren's syndrome (SS) were developed and validated between 1989 and 1996 by the European Study Group on Classification Criteria for SS, and broadly accepted. These have been re-examined by consensus group members, who have introduced some modifications, more clearly defined the rules for classifying patients with primary or secondary SS, and provided more precise exclusion criteria.

Current issues in Sjögren's syndrome

Sjögren's syndrome is a chronic autoimmune and rheumatic disorder with prominent sicca complaints from the mucous membranes because of lack of proper exocrine secretions. There is no straightforward and simple diagnostic test for Sjögren's syndrome, although several classification criteria have been designed including several oral diagnostic tests. A new set of classification criteria in a joint effort by research groups in Europe and USA has recently been presented. A large number of autoantibodies have been reported in Sjögren's syndrome where, in some cases, the antibodies are correlated with the extent and severity of disease. The finding of serum autoantibodies directed against the muscarinic M3 receptor is an important advance in understanding the pathogenesis of not only the impaired glandular function but also associated features of autonomic dysfunction in some patients. The treatment of primary Sjögren's syndrome is still mainly symptomatic.

Risk factors for positive minor salivary gland biopsy findings in Sjögren's syndrome and dry mouth patients

OBJECTIVE

To investigate risk factors for positive minor salivary gland biopsy results in Sjögren's syndrome (SS) and dry mouth patients.

METHODS

A total of 289 patients with dry mouth symptoms were evaluated. Potential risk factors for positive minor salivary gland biopsy results (>1 focus of lymphocytes) were studied in 2 phases. In phase 1, predictor variable candidates were identified for the test study (phase 2). Odds ratios were calculated for predictor variables.

RESULTS

IgG, IgA, keratoconjunctivitis sicca, and sex, identified as the best predictor variables from phase 1 data, were included in a logistic regression model using phase 2 data. Only IgG demonstrated association with biopsy results (chi(2) = 20.4, P = 0.0001). An elevated IgG level (>1,482 mg/dl) had a high specificity (97% and 97%), high positive predictive value (PPV) (97% and 97%), but poor sensitivity (40% and 45%) in predicting positive biopsy results and SS, respectively.

CONCLUSION

Elevated serum IgG levels best predicted a positive biopsy result and SS with high PPV and specificities.

Pseudoxanthoma Elasticum Masquerading as Sjögren’s Syndrome

Pseudoxanthoma elasticum is an inherited disorder of abnormal calcification of elastic fibers in the skin, retina, and cardiovascular system. Herein, we report a patient who had dry eyes and mouth, keratoconjunctivitis sicca, and a low titer ANA at presentation. A lip biopsy was performed to confirm a clinical suspicion of Sjögren's syndrome; however, the histologic findings were diagnostic of pseudoxanthoma elasticum. Antibodies to Ro and La were negative. Subsequently, she was found to have skin and eye findings consistent with pseudoxanthoma elasticum. Although a causal relationship between keratoconjunctivitis sicca and pseudoxanthoma elasticum is not proven, salivary gland involvement with pseudoxanthoma elasticum may explain this patient's symptoms. Physicians should consider the diagnosis of pseudoxanthoma elasticum in patients who present with sicca symptoms without obvious cause, especially if cutaneous or ophthalmologic abnormalities, or both, are present. Careful monitoring for associated problems is needed as soon as pseudoxanthoma elasticum is diagnosed.

Xerostomia and the geriatric patient

Saliva is essential for the preservation of oral-pharyngeal health, and disorders of salivary physiology are associated with numerous oral and pharyngeal problems, particularly in older people. Although salivary function is remarkably intact in healthy aging, medical problems, medications, and head and neck radiotherapy can cause salivary dysfunction and complaints of xerostomia among older people. Sjögren's syndrome, an autoimmune exocrinopathy, is the most common medical disease associated with salivary dysfunction. Medications with anticholinergic side effects will impair salivary output, and head and neck radiotherapy for cancer will cause permanent destruction of salivary glands. Treatments for salivary problems are based upon establishing a diagnosis, protecting oral and pharyngeal health, stimulating remaining glands, and replacing lost salivary fluids.

The oral side of Sjögren syndrome. Diagnosis and treatment. A review

Sjögren syndrome (SS) is an inflammatory disease of the exocrine glands. Although not always present, signs and symptoms of dry eyes and xerostomia are characteristic features of SS. Oral dryness is one of the most important data of patients with SS. Several sets of criteria have been published; however, there is no definitive agreement concerning which is the most useful. In addition to its various clinical manifestations, lack of understanding of the causes of SS delays prompt diagnosis. Histologically, the salivary gland shows a characteristic lymphocytic infiltrate, which is implicated in the destruction of gland cells. Saliva performs an important role in maintaining and protecting oral health. Deficient quality and quantity of saliva have a detrimental consequence for dental and oral health. In some patients, appropriate information regarding dry mouth care is not offered because most professionals either neglect or ignore adequate attention to oral health. Therefore, lack of treatment is frequent. Medical and dental studies that focus on the oral aspects of diagnosis, consequences, and treatment of SS are commented on. Diagnostic methods used for the oral component are also reviewed. The role of the oral tests developed to diagnose SS is assessed, especially tests used by the majority of criteria. Impairment of salivary secretion increases the risk of developing oral diseases; the therapeutic modalities designed to ameliorate these damages by increasing salivary output or by substitution of saliva are reviewed. We discuss published prevention techniques to diminish dental, periodontal, and soft tissue infections.

Minor Salivary Gland Punch Biopsy for Evaluation of Sjögren’s Syndrome

Incisional biopsy of labial salivary glands has been a valuable technique for diagnosis of Sjögren's syndrome. This report describes a new technique using punch biopsies that requires fewer resources and appears to be equally effective. Fifty patients evaluated by punch biopsy all yielded adequate pieces averaging 6 glands per specimen. Two patients had transient numbness of the lip. There were no other complications. Classical findings of Sjögren's histopathology were demonstrable with these specimens. This technique is safe, less expensive, and is proposed as a reliable alternative to incisional biopsy.

Use of muscarinic agonists in the treatment of Sjögren's syndrome

Two muscarinic agonists (pilocarpine and cevimeline) have recently been approved for the treatment of symptoms of xerostomia in Sjögren's syndrome (SS). These agents stimulate the M1 and M3 receptors present on salivary glands, leading to increased secretory function. The use of these agents emphasizes the importance of neuroendocrine mechanisms in SS, which is considered an autoimmune disorder. We review recent studies on the release of cytokines and metalloproteinases in SS-affected glands and their influence on the release of and response to neurotransmitters. Also, we review the structure and function of muscarinic receptors as they may relate to SS and the potential use of novel muscarinic agonists in SS.

The management of Sjögren's syndrome in dental practice

BACKGROUND

Sjögren's syndrome, or SS, is a multisystem inflammatory disorder of the exocrine glands with a wide range of extraglandular involvement. Symptoms of dry eyes and xerostomia, although not invariably present, are characteristic features of SS. An increased risk of oral and dental diseases is a prominent consequence of SS.

TYPES OF STUDIES REVIEWED

The author reviewed recent medical and dental studies that have advanced our understanding of the causes and treatment of SS. She particularly focused on studies addressing the diagnosis and treatment of the oral component of the disease.

RESULTS

Sjögren's syndrome is a widely underdiagnosed disease. A delay in the diagnosis of SS may have a significant physical, psychological and economic impact on the affected person. The pathogenesis of SS appears to involve a number of factors: immunological, genetic, hormonal and possibly infectious. Successful management of SS requires a multidisciplinary approach, and the dentist plays an essential role in the diagnosis and treatment of the disease. ORAL IMPLICATIONS: Impairment of salivary function in SS increases the risk of developing oral diseases. Effective management of oral health comprises enhancement of salivary output (cholinergic agonist drugs such as pilocarpine or cevimeline) and prevention and treatment of dental caries, oral candidiasis and allergic mucositis. Finally, periodic evaluation of various clinical and laboratory parameters is needed to monitor disease status.

Differential expression of matrix metalloproteinases in labial salivary glands of patients with primary Sjögren's syndrome

OBJECTIVE

To determine the enzymatic activity and cellular localization of matrix metalloproteinases (MMPs) 2, 3, and 9 in labial salivary glands from patients with different degrees of severity of primary Sjogren's syndrome (primary SS).

METHODS

Gelatinase activity was determined by zymography and quantified by densitometry. The specificity of MMPs was determined using protease inhibitors and chelators, as well as activators of the latent forms of these enzymes. The cellular localization of MMPs was carried out using monoclonal antibodies that recognize their latent and active forms.

RESULTS

Labial glands from control subjects and patients showed gelatinase activity for MMP-2 and MMP-9. Activation studies revealed that both enzymes were predominantly present in their latent forms. The highest levels of MMP-9 activity were detected in patients with severe, active, primary SS (except for patients with severe clinical symptoms for extended periods) and correlated with structural and functional glandular changes. MMP-2 activity was almost the same in patients and controls. MMPs were detected by immunolocalization only in acinar and ductal cells and were homogeneously distributed throughout patients' glands. MMP-2 and MMP-9 expression paralleled their gelatinase activity. MMP-3, detectable only with immunologic methods, was absent in control subjects but abundantly expressed in patients. Importantly, MMP protein levels in acinar and ductal cells were independent of either the presence or the proximity of mononuclear infiltrate cells.

CONCLUSION

MMP-3 and MMP-9 expression, as well as MMP-9 catalytic activity, were increased in tissue samples from SS patients in a manner that correlated with the severity of the disease. Most important, increased MMP activity stemmed from exocrine epithelial cells and was not due to infiltrating lymphocytes. Thus, changes in salivary glands as a consequence of proteolysis may lead to severe glandular destruction.

Severe destructive autoimmune lesions with aging in murine Sjögren's syndrome through Fas-mediated apoptosis

When we evaluated the age-associated changes in autoimmune exocrinopathy in a NFS/sld murine model for primary Sjögren's syndrome (SS), severe destructive autoimmune lesions developed in the salivary and lacrimal glands in the aged mice, compared with those observed in the younger model. We detected a decreased secretion of saliva and tear flow in the aged group. A significant increase of TUNEL(+)-apoptotic epithelial duct cells in the salivary glands was detected in the aged SS animal model. A higher proportion of mouse salivary gland cells bearing Fas was found in the aged group, whereas no significant changes were seen on tissue-infiltrating CD4(+) T cells bearing FasL in the salivary glands from young and aged mice. We detected an increased cleavage product of organ-specific autoantigen, 120-kd alpha-fodrin, in the aged salivary gland tissues on immunoblotting, and an increase in serum autoantibody production against 120-kd alpha-fodrin by enzyme-linked immunosorbent assay. An increase in the proliferative response of splenic T cells against organ-specific autoantigen was observed, whereas nonspecific concanavalin A responsiveness was decreased in the aged mice. In addition, a decrease in Fas expression was found on splenic CD4(+) T cells in the aged mice, and anti-Fas mAb-stimulated apoptosis was down-regulated on CD4(+) T cells. These results indicate that age-associated dysregulation of CD4(+) T cells may play a crucial role on acceleration of organ-specific autoimmune lesions in a murine model for primary SS through Fas-mediated apoptosis.

Primary Sjögren's syndrome (pSS): subjective symptoms and salivary findings

We studied the relationship between dry mouth, general health and objective findings in 16 patients having primary Sjögren's syndrome (pSS) according to the 1993 European classification criteria as well as in healthy controls. Serum autoantibody to SSA/SSB (AB) was correlated to unstimulated whole saliva flow (UWS) and labial salivary gland focus score (FS). All patients had dry mouth symptoms and UWS < or = 0.10 ml/min, but patients with UWS < 0.05 ml/min and AB had more complaints of oral and ocular dryness. These patients also tended to have more exocrine and non-exocrine manifestations, and oral dryness had a greater impact on their self-reported general health than in patients with UWS > or = 0.05 ml/min. Accordingly, we consider rating of oral dryness by visual analogue scales or categorised questionnaires to be valuable for the evaluation of oral involvement in pSS.

Estrogen deficiency accelerates autoimmune exocrinopathy in murine Sjögren's syndrome through fas-mediated apoptosis

Estrogenic action has been suggested to be responsible for the strong female preponderance of autoimmune diseases, but the role of estrogens in the female has not been well characterized. We evaluated the effects of estrogen deficiency in a murine model for autoimmune exocrinopathy of Sjögren's syndrome (SS). Severe destructive autoimmune lesions developed in the salivary and lacrimal glands in estrogen-deficient mice, and these lesions were recovered by estrogen administration. We detected an intense estrogen receptor in splenic CD8(+) T cells compared with that in CD4(+) T cells, and concanavalin-A-stimulated blastogenesis of splenic CD8(+) T cells with estrogens was much higher than that of CD4(+) T cells. We found a significant increase in serum autoantibody production against the organ-specific autoantigen alpha-fodrin. Moreover, an increased proportion of TUNEL+ apoptotic epithelial duct cells was observed in estrogen-deficient mice. It was demonstrated that Fas-mediated apoptosis in cultured salivary gland cells was clearly inhibited by estrogens in vitro. These results indicate that dysfunction of regulatory T cells by estrogen deficiency may play a crucial role on acceleration of organ-specific autoimmune lesions, and estrogenic action further influences target epithelial cells through Fas-mediated apoptosis in a murine model for SS.

Primary sialoangiectasia--a diagnostic pitfall in Sjögren's syndrome: case report

A case of primary sialoangiectasia, which in this case was initially misdiagnosed as Sjögren's syndrome, is described. Other diseases, including HIV infection, psoriatic arthritis, and acute parotitis, may cause glandular changes similar to the changes found in the syndrome. Therefore, sialography must be combined with other methods of assessment of the oral cavity when suspicion is high for Sjögren's syndrome. Properly applied, sialography provides essential information regarding the severity of glandular damage and the progression of the disease.

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

The aim of this study was to investigate the production of anti-Ro/SS-A and anti-La/SS-B antibodies in peripheral blood (PB) of patients with Sjögren's syndrome (SS). The ELISPOT method was performed to quantify the frequency of PB lymphocytes spontaneously secreting anti-Ro/SS-A and/or anti-La/SS-B antibodies. The total number of IgG-, IgA- and IgM-producing cells was also quantified. The recombinant Ro 52-kD, Ro 60-kD and La 48-kD proteins were used as target antigens. Three of 18 SS patients had PB lymphocytes secreting IgG antibodies against the recombinant Ro 52-kD protein. The same three patients had high serum titres of anti-Ro 52-kD antibodies. In addition, these patients were classified as having severe disease, and all three had focus scores of >/= 8 in biopsies of the labial salivary glands (LSG). The correlation between the number of PB cells producing IgG antibodies against the recombinant Ro 52-kD protein and the focus score was significant (P < 0.01). The results indicate that only SS patients with severe disease and high degree of local inflammation in LSG have B cells producing anti-Ro/SS-A antibodies in PB. Thus, most of the spontaneous autoantibody production must take place in other body compartments, e.g. in exocrine glands and probably also in the lymphoid organs and/or other mucosal sites.

Accelerated onset of age-related autoimmune lesions in MRL/+ mice by ovariectomy

MRL/Mp +/+ (MRL/+) mice, not bearing the lpr gene, are known to have age-related autoimmune lesions in several organs such as pancreas, salivary and lacrimal glands at 30-weeks-old or more. In this study, MRL/+ mice were ovariectomized at 4-weeks-old, and their natural histories were analysed. Ovariectomy (Ovx) of MRL/+ mice led to marked acceleration of organ-specific autoimmune lesions exclusively in the salivary and lacrimal glands at 8-weeks-old or more, whereas no significant inflammatory change was observed in the pancreas. In the vast majority of inflammatory infiltrates, CD3+ CD4+ T cells were predominant in both the salivary and lacrimal glands of Ovx-MRL/+ mice. Up-regulated expression of cytokine genes including IL-1 beta, TNF-alpha, IL-2, interferon (IFN)-gamma, and IL-6 was detected in the salivary gland of Ovx-MRL/+ mice by reverse transcriptase (RT)-PCR analysis. FACS analysis of spleen cells of Ovx-mice revealed increase in I-Ak expression on B220+ cells, and autoantibody production against the salivary gland-specific antigen in sera from Ovx-MRL/+ mice, but not in control mice. These results suggest that age-related autoimmunity in the salivary and lacrimal glands were accelerated in Ovx-MRL/+ mice, and that autoreactive Th1 cells were activated associated with organ-specific autoantibody production.

Analysis of the concentration and output of whole salivary constituents in patients with Sjögren's syndrome

In Sjögren's syndrome, salivary glands are affected, resulting in a diminished salivary flow. In the present study, the protein composition, sialic acid content and the amounts of calcium and phosphate of stimulated whole saliva from 43 patients with Sjögren's syndrome, were compared with those of control saliva samples from 17 healthy subjects. The absolute concentrations of albumin, cystatin C, cystatin S, total IgA and total protein, but not amylase, were increased significantly in both primary and secondary Sjögren's syndrome. The output/min of total protein, albumin, amylase, and IgA was, however, decreased in Sjögren patients. These results suggest that the diminished output of salivary defence factors, rather than their absolute concentrations, may be related to the oral health problems seen in Sjögren's syndrome patients.

Sjogren's syndrome: clinical spectrum and current diagnostic controversies

Although we have had a useful and internationally agreed-upon definition of Sjögren's syndrome (SS) for more than 30 years, we have not yet agreed upon criteria for diagnosing it. Understanding the clinical spectrum of SS and the various tests used to diagnose its components provides a basis for discussing controversies about diagnostic criteria. A review of the clinical features of SS and their diagnostic tests is followed by assessments of seven sets of diagnostic criteria and a proposal for future criteria. The various existing criteria use different combinations of clinical features and tests, which results in populations of different sizes and homogeneities being given the diagnosis of SS. Some criteria propose alternative tests in diagnosing components of SS, while others do not. Internationally accepted diagnostic criteria for SS that are as disease-specific as possible are needed for us to learn the epidemiology, pathogenesis, treatment, and prognosis of this clinically and scientifically important disease.

Is sialography effective in diagnosing the salivary component of Sjögren's syndrome?

Parotid sialography has been used for many years as a means of assessing salivary glands in Sjögren's syndrome (SS), and it is occasionally used as a diagnostic criterion for the salivary component of SS. To assess its diagnostic effectiveness, we reviewed studies in which sialography was applied to patients with SS and control subjects for the purpose of estimating its diagnostic sensitivity and specificity or comparing it with other means of assessing salivary glands. Sialography appears to be diagnostically less sensitive but more specific than salivary flow rate measurement and more sensitive but less specific than labial salivary gland (LSG) biopsy. Such calculations are based on the diagnosis of SS established in each study, but the various studies used widely different criteria to establish that diagnosis. Therefore, these calculations are not based on a consistent standard, and comparison between the calculations may be misleading, which underscores the need to develop internationally accepted diagnostic criteria for SS. Studies conducted so far have not shown that parotid sialography is either a sensitive indicator of the salivary component of SS or more closely associated than LSG biopsy with keratoconjunctivitis sicca, the only other component of primary SS with which ultimately to assess diagnostic specificity.

Sjögren's syndrome: immunobiology of exocrine gland dysfunction

Sjögren's syndrome is an autoimmune disorder characterized by dryness of the eyes and mouth. The frequency of this disorder remains controversial, due to absence of a universally accepted classification system. In the San Diego and San Francisco classification systems for primary Sjögren's syndrome, evidence for an autoimmune process and focal lymphocytic infiltration of the salivary or lacrimal gland is required for diagnosis. This paper reviews the genetic and environmental factors that have been associated with the autoimmune process in Sjögren's syndrome. Key immunopathologic features include: (a) an increased prevalence of particular HLA-DR/DQ alleles; (b) induction of HLA-DR/DQ proteins on the epithelial cells in salivary and lacrimal gland biopsies; (c) infiltration of the glands by CD4+ T-cells that transcribe IL-2 and IFN-gamma; (d) induction of granzyme A and perforin in CD4+ T-cells, suggesting a mechanism of cellular destruction of the glands; (e) clonal expansion of B-cells that use a particular light chain within the salivary gland; (f) production of autoantibodies against nuclear antigens SS-A (60 and 52 kDa) and SS-B (48 kDa), indicating a failure of normal tolerance mechanisms; and (g) increased frequency of B-cell non-Hodgkin's lymphoma. Indirect evidence has suggested a potential role for viruses (especially members of the herpesvirus and retroviral family) as co-factors.

Autoantibodies to DNA-dependent protein kinase. Probes for the catalytic subunit

DNA-dependent protein kinase (DNA-PK) is an important nuclear enzyme which consists of a catalytic subunit known as DNA-PKcs and a regulatory component identified as the Ku autoantigen. In the present study, we surveyed 312 patients in a search for this specificity. 10 sera immunoprecipitated a large polypeptide which exactly comigrated with DNA-PKcs in SDS-PAGE. Immunoblot analysis demonstrated that this polypeptide was recognizable by a rabbit antiserum specific for DNA-PKcs. Although the patient sera did not bind to biochemically purified DNA-PKcs in immunoblots or ELISA, they were able to deplete DNA-PK catalytic activity from extracts of HeLa cells in a dose-dependent manner. We conclude that these antibodies should be useful probes for studies which aim to define the role of DNA-PK in cells. Since six sera simultaneously contained antibodies to the Ku protein, these studies suggest that relatively intact forms of DNA-PK complex act as autoantigenic particles in selected patients.

Assessment of the European classification criteria for Sjögren's syndrome in a series of clinically defined cases: results of a prospective multicentre study. The European Study Group on Diagnostic Criteria for Sjögren's Syndrome

OBJECTIVE

To assess the recently proposed preliminary criteria for the classification of Sjögren's syndrome (SS) in a multicentre European study of a new series of clinically defined cases.

METHODS

The criteria included six items: I = ocular symptoms; II = oral symptoms; III = evidence of keratoconjunctivitis sicca; IV = focal sialoadenitis by minor salivary gland biopsy; V = instrumental evidence of salivary gland involvement; VI = presence of autoantibodies. Each centre was asked to provide five patients with primary SS, five with secondary SS, five with connective tissue diseases (CTD) but without SS, and five controls (patients with ocular or oral features that may simulate SS). The preliminary six item classification criteria set was applied to both the SS patients and the non-SS controls, and the performance of the criteria in terms of sensitivity and specificity was tested.

RESULTS

The criteria set was tested on a total of 278 cases (157 SS patients and 121 non-SS controls) collected from 16 centres in 10 countries. At least four of the six items in the criteria set (limiting item VI to the presence of Ro(SS-A) or La(SS-B) antibodies) were present in 79 of 81 patients initially classified as having primary SS (sensitivity 97.5%), but in only seven of 121 non-SS controls (specificity 94.2%). When the presence of item I or II plus any two of items III-V of the criteria set was considered as indicative of secondary SS, 97.3% (71 of 73) of the patients initially defined as having this disorder and 91.8% (45 of 49) of the control patients with CTD without SS were correctly classified.

CONCLUSION

This prospective study confirmed the high validity and reliability of the classification criteria for SS recently proposed by the European Community Study Group.

Vth International Symposium on Sjögren's syndrome. Clinical aspects and therapy

There is increasing awareness that sicca syndrome can lead to ocular, oral and systemic complications. However, a wide variety of pathogenetic processes may lead to the same end result of diminished glandular secretion. Recognition of these different etiologies will lead to improved therapies. On the one hand, an active inflammatory/autoimmune process may respond to immunomodulatory drugs. On the other hands, processes that predominantly involve "neuroendocrine" dysfunction (unrelated to immune activity) of the gland will require a different approach.