Salivary gland immunoglobulin and rheumatoid factor synthesis in Sjögren's syndrome. Natural history and response to treatment

Predicting lymphoma development in patients with Sjögren's syndrome

Introduction: The issue of predicting lymphoma in primary Sjögren's syndrome (pSS) starts from its clinical and biologic essence, i.e., an autoimmune exocrinopathy with sicca syndrome, inflammation and lymphoproliferation of MALT (mucosa-associated lymphoid tissue) in exocrine glands. Areas covered: The two major predictors to be firstly focused are persistent salivary gland (SG) swelling and cryoglobulinemic vasculitis with related features as purpura and low C4, or the sole serum cryoglobulinemia repeatedly detected. They are pathogenetically linked and reflect a heavier MALT involvement by histopathology, with the expansion of peculiar rheumatoid factor (RF)-positive clones/idiotypes. Other predictors include lymphadenopathy, splenomegaly, neutropenia, lymphopenia, serum beta2-microglobulin, monoclonal immunoglobulins, light chains, and RF. Composite indexes/scores may also predict lymphoma. Expert opinion: Prediction at baseline needs amelioration, and must be repeated in the follow-up. Careful clinical characterization, with harmonization and stratification of large cohorts, is a relevant preliminary step. Validated and new biomarkers are needed in biologic fluids and tissues. SG echography with automatic scoring could represent a future imaging biomarker, still lacking. Scoring MALT involvement in pSS, as an additional tool to evaluate disease activity and possibly to predict lymphoma, is welcomed. All these efforts are now ongoing within the HarmonicSS project and in other research initiatives in pSS.

Tertiary Lymphoid Structures: Autoimmunity Goes Local

Tertiary lymphoid structures (TLS) are frequently observed in target organs of autoimmune diseases. TLS present features of secondary lymphoid organs such as segregated T and B cell zones, presence of follicular dendritic cell networks, high endothelial venules and specialized lymphoid fibroblasts and display the mechanisms to support local adaptive immune responses toward locally displayed antigens. TLS detection in the tissue is often associated with poor prognosis of disease, auto-antibody production and malignancy development. This review focuses on the contribution of TLS toward the persistence of the inflammatory drive, the survival of autoreactive lymphocyte clones and post-translational modifications, responsible for the pathogenicity of locally formed autoantibodies, during autoimmune disease development.

Mastitis associated with Sjögren's syndrome: a series of nine cases

Sjögren's syndrome is well known to target exocrine glands, especially lacrimal and salivary glands, which share with mammary glands anatomical, histological, and immunological features. Herein, we investigated the mammary involvement in patients with Sjögren's syndrome and compared the histological findings with minor salivary gland involvement. We reviewed the charts of patients with Sjögren's syndrome (followed in Montpellier University Hospital, between January 2000 and January 2015), in whom minor salivary gland and mammary tissues were available. Two expert pathologists analysed retrospectively these tissues in order to identify inflammatory patterns. Immunohistochemical stainings were performed to precise leucocyte distribution. Sixteen Sjögren's syndrome patients with available salivary and breast tissue samples were included. All were women, with a median age of 60.1 ± 11.3 years at Sjögren's syndrome diagnosis. Mammary biopsy was conducted because of breast symptoms in 6 patients and following imaging screening strategies for breast cancer in 10 patients. Nine patients exhibited an inflammatory breast pattern (lymphocytic infiltrates or duct ectasia), close to minor salivary gland histological findings. Immunohistochemical stainings (n = 5) revealed B and T cell infiltrates within breast tissue, with a higher proportion of T CD4+ cells, but no IgG4-secreting plasma cells were found. This is the first series to describe breast inflammatory patterns in Sjögren's syndrome. Mastitis is in line with the classical involvement of exocrine glands in this disease. These findings are consistent with the literature data considering Sjögren's syndrome as an "autoimmune epithelitis".

Natural History and Predictors of Progression to Sjögren's Syndrome Among Participants of the Sjögren's International Collaborative Clinical Alliance Registry

OBJECTIVE

To explore changes in the phenotypic features of Sjögren's syndrome (SS), and in SS status among participants in the Sjögren's International Collaborative Clinical Alliance (SICCA) registry over a 2-3-year interval.

METHODS

All participants in the SICCA registry who were found to have any objective measures of salivary hypofunction, dry eye, focal lymphocytic sialadenitis in minor salivary gland biopsy, or anti-SSA/SSB antibodies were recalled over a window of 2 to 3 years after their baseline examinations to repeat all clinical examinations and specimen collections to determine whether there was any change in phenotypic features and in SS status.

RESULTS

As of September 15, 2013, a total of 3,514 participants had enrolled in SICCA, and among 3,310 eligible, 771 presented for a followup visit. Among participants found to have SS using the 2012 American College of Rheumatology (ACR) classification criteria, 93% again met the criteria after 2 to 3 years, and this proportion was 89% when using the 2016 ACR/European League Against Rheumatism (EULAR) criteria. Among those who did not meet ACR or ACR/EULAR criteria at baseline, 9% and 8%, respectively, had progressed and met them at followup. Those with hypergammaglobulinemia and hypocomplementemia at study entry were, respectively, 4 and 6 times more likely to progress to SS by ACR criteria than those without these characteristics (95% confidence interval 1.5-10.1 and 1.8-20.4, respectively).

CONCLUSION

While there was stability over a 2-3-year period of both individual phenotypic features of SS and of SS status, hypergammaglobulinemia and hypocomplementemia at study entry were predictive of progression to SS.

A review of salivary gland histopathology in primary Sjögren's syndrome with a focus on its potential as a clinical trials biomarker

Salivary gland changes, characterised by a focal lymphocytic sialadenitits, play an important role in the diagnosis of primary Sjögren's syndrome (PSS) and were first described over 40 years ago. Recent evidence suggests that minor salivary gland biopsy may also provide information useful for prognostication and stratification, yet difficulties may arise in the histopathological interpretation and scoring, and evidence exists that reporting is variable. With the increasing number of actual and proposed clinical trials in PSS, we review the evidence that might support the role of histopathology as a biomarker for stratification and response to therapy and highlight areas where further validation work is required.

Cryoglobulinaemia related to Sjogren's syndrome or HCV infection: differences based on the pattern of bone marrow involvement, lymphoma evolution and laboratory tests after parotidectomy

OBJECTIVE

The relationship of cryoglobulinaemia with lymphoproliferation of mucosa-associated lymphoid tissue (MALT) as risk factors for lymphoma evolution in SS remains to be clarified. The different biologic background of SS-related cryoglobulinaemia as compared with cryoglobulinaemia linked to HCV infection was clarified by different clinical and biologic approaches.

METHODS

B-cell clonal expansion was analysed in the bone marrow of 27 consecutive cases with primary SS and mixed cryoglobulinaemia, HCV unrelated, in comparison with 55 HCV-related patients with cryoglobulinaemic vasculitis (CV) without SS. The results were related to the possible occurrence and localization of B-cell lymphoma in the single case. Secondly, the prevalence of mixed cryoglobulinaemia was investigated in 41 unselected patients with primary SS showing either parotid myoepithelial sialadenitis (MESA) or a frank B-cell non-Hodgkin's lymphoma. Thirdly, the levels of serum cryoglobulins and RF were followed in one patient with primary SS, CV and parotid B-cell lymphoma of MALT after bilateral subtotal parotidectomy.

RESULTS

A polyclonal pattern of B expansion in the bone marrow was significantly more frequent in SS-related (19/27 cases) than in HCV-related cryoglobulinaemia (19/55) (P = 0.003). Cryoglobulins were positive in a fraction of patients with SS and malignant lymphoma or with parotid MESA (13/18 and 7/23, respectively), whereas MALT involvement by the lymphoproliferative disorder was the rule. Finally, the levels of serum cryoglobulins and RF markedly decreased in the SS patient undergoing bilateral subtotal parotidectomy.

CONCLUSION

Lymphoproliferation of MALT appears as the biologic background of cryoglobulinaemia in SS, differently from HCV-related cryoglobulinaemia.

Proteomic analysis of saliva: a unique tool to distinguish primary Sjögren's syndrome from secondary Sjögren's syndrome and other sicca syndromes

Introduction

A growing interest has arisen in salivary proteomics as a tool for the identification of biomarkers for primary Sjögren's syndrome (pSS). Nonetheless, only a limited number of preclinical validation studies have been performed, limiting the possibility of translating proteomic results into clinical practice. The primary aim of this study was to refine the diagnostic power of a panel of candidate salivary biomarkers described in pSS with respect to both healthy volunteers and pathological controls. We also explored the pathogenetic function of the detected putative biomarkers both in the local exocrinopathy and in the systemic inflammatory processes of SS.

Methods

One hundred and eighty patients were included in the study overall. In the first "exploratory phase", we enrolled 40 females with pSS, 40 sex- and age-matched healthy volunteers, 10 patients with sicca non-SS and 15 secondary SS (sSS) patients. The testing cohort of the second "challenge phase" of the study was represented by 75 unselected, consecutive subjects: 19 pSS, 21 healthy volunteers, 10 sicca non-SS and 25 sSS patients. Salivary proteomic analysis was performed combining two-dimensional electrophoresis (2DE) and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). Western blot (WB) analysis and enzyme-linked immunosorbent assay (ELISA) were employed to validate 2DE results. Ingenuity Pathway Analysis (IPA) Knowledge base was adopted to associate candidate biomarkers in a signalling pathogenetic network.

Results

A total of 28, 6, 7 and 12 protein spots were found to be significantly different in pSS samples with respect to healthy volunteers, non-SS sicca syndrome, SSc-sSS and rheumatoid arthritis-sSS, leading to the identification of 15 differently expressed proteins. Among them, α-amylases precursor, carbonic anhydrase VI, β-2 microglobulin, glyceraldehydes-3-phosphate dehydrogenase (G3PDH), epidermal fatty acid binding protein (E-FABP) and immunoglobulin k light chain (IGK-light chain) apparently showed the most significant differences in pSS when compared to healthy volunteers and non-SS pathological controls. On the other hand, as expected, pSS and sSS salivary profiles shared a great number of similarities.

Conclusions

This study demonstrated that salivary fluid might represent a novel ideal milieu for the detection of a diagnostic panel of candidate biomarkers for pSS, and to gain an insight into the pathogenetic processes underlying glandular and systemic autoimmune disorders.

Sjögren's syndrome: History, clinical and pathological features

The history, ocular and oral clinical features, and histopathology of Sjögren's syndrome are described. Primary Sjögren's syndrome is defined when only the ocular and oral components are present, while the secondary form refers to the association with a connective tissue disorder, especially rheumatoid arthritis, or other illness such as AIDS, hepatitis C infection, or biliary cirrhosis. Sjögren's syndrome is a common, but often overlooked disorder. Patients with severe disease run a forty-times risk of developing lymphoma usually of the B cell type.

Labial salivary gland biopsies in Sjögren's syndrome: still the gold standard?

OBJECTIVES

The accuracy and diagnostic benefits of the labial salivary gland (LSG) biopsy for Sjögren's syndrome (SS) have received mixed reviews. This study was conducted to assess (1) the inter-rater agreement among 5 pathologists, and (2) the relationship between biopsy findings and clinical disease parameters.

STUDY DESIGN

Three oral pathologists (OP) and two surgical pathologists (SP) provided independent diagnoses, focus scores, and plasma cell characterizations for 37 LSG biopsies. Inter-rater reliability was assessed using percentage of overall agreement and intraclass correlation coefficients. Relationships between diagnoses and clinical parameters were assessed by nonparametric correlations.

RESULTS

Overall agreement among the pathologists was poor, although the intra-specialty agreement was good. The ratings of OP were most highly correlated with serological measures, while those of SP were correlated with salivary flow rate and disease damage.

CONCLUSION

Since the LSG biopsy can be the determining factor in SS diagnoses, these demonstrated inconsistencies merit further consideration.

Do salivary antibodies reliably reflect both mucosal and systemic immunity?

Two major antibody classes operate in saliva: secretory IgA (SIgA) and IgG. The former is synthesized as dimeric IgA by plasma cells (PCs) in salivary glands and is exported by the polymeric Ig receptor (pIgR). Most IgG in saliva is derived from serum (mainly via gingival crevices), although some is locally produced. Gut-associated lymphoid tissue (GALT) and nasopharynx-associated lymphoid tissue (NALT) do not contribute equally to mucosal PCs throughout the body. Thus, enteric immunostimulation is an inadequate mode of stimulating salivary IgA antibodies, which are poorly associated with the intestinal SIgA response, for instance after enteric cholera vaccination. Nevertheless, the IgA response in submandibular/sublingual glands is better related to B cell induction in GALT than the parotid response. Such disparity is suggested by the elevated levels of IgA in submandibular secretions of AIDS patients, paralleling their highly upregulated intestinal IgA system. Moreover, in patients with active celiac disease, IgA antibodies to disease-precipitating gliadin are reliably represented in whole saliva but not in parotid secretion. Parotid SIgA may be more consistently linked to immune induction in palatine tonsils and adenoids (human NALT), as supported by the homing molecule profile of NALT-derived B cell blasts. Also several other variables influence the levels of antibodies in oral secretions. These include difficulties with reproducibility and standardization of immunoassays, the impact of flow rate, acute or chronic stress, protein loss during sample handling, and uncontrolled admixture of serum-derived IgG and monomeric IgA. Despite such problems, saliva remains an interesting biological fluid with great scientific and clinical potentials.

Immunoprofile of focal lymphocytic infiltration in minor salivary glands of healthy individuals

AIM

To characterize the immunohistochemical profile of the inflammatory cells included in the focal lymphocytic infiltration in the minor salivary glands of healthy individuals.

MATERIALS AND METHODS

Tissue samples of the labial and palatal salivary glands from 46 postmortem subjects, demonstrating the presence of focal lymphocytic infiltration were quantitatively evaluated for the presence of T- and B-cell lymphocytes, plasma cells and macrophages by immunohistochemical and morphometric methods.

RESULTS

B-cell lymphocytes, the predominant cell population in labial (67.5%) and palatal salivary glands (60.8%), were more frequent than T-cell lymphocytes in both glands (P < 0.001). Among the T-cell lymphocytes, CD(4)-positive cells were significantly more prevalent than the CD(8)-positive cells (P < 0.001). Plasma cells were almost absent, comprising only 0.01% of the focal lymphocytic infiltration cells of the labial and palatal salivary glands.

CONCLUSIONS

Focal lymphocytic infiltration in the samples of the salivary glands obtained from healthy individuals is devoid of plasma cells. This can serve as an additional means to differentiate between focal lymphocytic infiltration in patients with Sjögren's syndrome, in which plasma cells are abundant, and focal lymphocytic infiltration in individuals with other causes of focal sialadenitis.

Clinical significance of quantitative immunohistology in labial salivary glands for diagnosing Sjögren's syndrome

OBJECTIVES

Because patients with primary Sjögren's syndrome (pSS) are at risk of developing other autoimmune phenomena and malignant lymphoma, it is important to distinguish pSS from non-Sjögren's (nSS) sicca syndrome. However, this distinction might be difficult because of the lack of a gold standard for pSS. We studied the clinical significance of quantitative immunohistology (QIH) in labial salivary glands for diagnosing pSS.

METHODS

In a model mimicking the making of a clinical diagnosis, five experts diagnosed 396 patients as nSS, 'indefinite', pSS or secondary SS (sSS) using 25 clinical parameters. Patients were diagnosed twice, namely without (yielding gold-standard diagnoses) and with knowledge of QIH. The numbers of changes in diagnosis from 'indefinite' to 'definite' (nSS, pSS or sSS) or vice versa were compared. Patient groups with vs without a changed diagnosis in the four gold-standard diagnosis groups were compared regarding objective autoimmune parameters.

RESULTS

Sensitivity, specificity, positive and negative predictive value for abnormal QIH in pSS vs nSS were 93, 86, 76 and 96%, respectively. Changes in diagnosis from 'indefinite' to 'definite' (31%) were found more often (P = 0.00) than changes from 'definite' to 'indefinite' (10%). Knowledge of QIH distinguished patient groups within the gold-standard nSS, indefinite and pSS patient group with regard to autoimmune parameters.

CONCLUSION

In view of the consequences of distinguishing pSS from nSS, these results point to an additional diagnostic role for QIH in clinical practice.

Lymphocytic infiltration and enlargement of the lacrimal glands: a new subtype of primary Sjögren's syndrome?

PURPOSE

To review the clinical, radiologic, serologic, histopathologic, immunohistochemical, and molecular genetic features of patients having Sjögren's syndrome (SS) with lacrimal gland enlargement.

DESIGN

Retrospective case series review.

PARTICIPANTS

Fourteen patients histopathologically diagnosed with SS with lacrimal enlargement. Twenty-three age- and gender-matched controls were used for comparison on radiologic analysis.

METHODS

Clinical and serologic data were determined directly or by chart review. Computed tomography images from patients were compared with those from the control group. Histopathologic sections were reviewed and graded using the Chisholm-Mason scale, and quantitative immunohistochemical analysis was applied.

MAIN OUTCOME MEASURES

Clinically, patients were assessed for age, gender, onset, symptoms and signs, systemic features, treatment, and outcome. Existing histologic specimens were reviewed according to the Chisholm-Mason scale, and then the percentages of plasma cells containing immunoglobulin (Ig) A, IgG, and IgM were determined. Imaging was assessed for lacrimal gland thickness, prolapse, density, and margin contour; extraocular muscle size; orbital tissue displacement; and proptosis.

RESULTS

Clinical and histopathological data fulfilled the revised American-European criteria for primary SS in 79% of patients. Compared with other large series of primary SS patients, similarities were found with age, xerophthalmia, parotidomegaly, and articular involvement. Differences included a lower incidence of autoantibodies, xerostomia, and extraglandular features and a higher male-to-female ratio. In almost all patients (93%), the percentage of plasma cells positive for IgA was less than 70%, consistent with SS. Compared with controls, the lacrimal glands were enlarged significantly (P<0.0001) and prolapsed (P<0.001). Involved glands had blurred margins (P<0.007), caused displacement of adjacent tissues (P = 0.03), and were associated with hyperdense fat (P = 0.007). Lymphocytic infiltration of orbital fat was present in all patients for whom fat biopsy results were available. Three patients had monoclonal infiltrates, and 1 patient experienced subsequent extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue type, 4 years after presentation.

CONCLUSIONS

The criteria used to diagnose primary SS are controversial, but both diagnostic and quantitative immunohistochemical criteria suggest that these patients, with lacrimal gland enlargement resulting from lymphocytic infiltration, represent a new subtype of primary SS. This is clinically important in view of the increased risk of lymphoma associated with SS, compared with idiopathic nonspecific lacrimal inflammation.

Preliminary classification of nonmalignant B cell proliferation in Sjögren's syndrome: perspectives on pathobiology and treatment based on an integrated clinico-pathologic and molecular study approach

A classification of nonmalignant lymphoproliferation in Sjögren's syndrome is presented, based on the results of international meetings regarding Sjögren's syndrome-associated lymphomagenesis and on our results of a clinico-pathologic and molecular study and long-term follow-up in well-characterized patients. Sjögren's syndrome pathobiology has similarities to hepatitis C virus-related B-cell lymphoproliferation. Antigen stimulation with the preferential expansion of rheumatoid factor-positive clones and specific immunoglobulin gene expression and recombination represent key biologic events in lymphoproliferation. This classification is based on the coupling of molecular and histological studies and may result in more selective treatment approaches.

Salivary gland mucosa-associated lymphoid tissue lymphoma immunoglobulin VH genes show frequent use of V1-69 with distinctive CDR3 features

Salivary gland mucosa associated lymphoid tissue (MALT) type lymphomas are B-cell neoplasms that develop out of a reactive infiltrate, often associated with Sjögren's syndrome. Previous reports from our laboratory involving 10 patients suggested these lymphomas expressed a restricted immunoglobulin (Ig)VH gene repertoire with over use ofV1-69 gene segments. To better determine the frequency ofV1-69 use and whether there may also be selection for CDR3 structures, we sequenced the VH genes from 15 additional cases. Over half of the potentially functionalVH genes (8 of 14) used aVH1 family V1-69 gene segment, whereas the other cases used different gene segments from theVH1 (V1-46),VH3 (V3-7, V3-11, V3-30.3, V3-30.5), and VH4(V4-39) families. The 8 V1-69 VHgenes used 5 different D segments in various reading frames, but all used a J4 joining segment. The V1-69 CDR3s showed remarkable similarities in lengths (12-14 amino acids) and stretches of 2 to 3 amino acids between the V-D and D-J junctions. They did not resemble CDR3s typical of V1-69 chronic lymphocytic leukemias. This study extends our earlier work in establishing that salivary gland MALT lymphomas represent a highly selected B-cell population. Frequent use of V1-69 appears to differ from MALT lymphomas that develop at other sites. The high degree of CDR3 similarity among the V1-69cases suggests that different salivary gland lymphomas may bind similar, if not identical epitopes. Although the antigen specificities are presently unknown, similar characteristic CDR3 sequences are often seen with V1-69 encoded antibodies that have anti-IgG or rheumatoid factor activity.

Salivary gland mucosa-associated lymphoid tissue lymphoma immunoglobulin VH genes show frequent use of V1-69 with distinctive CDR3 features

Salivary gland mucosa associated lymphoid tissue (MALT) type lymphomas are B-cell neoplasms that develop out of a reactive infiltrate, often associated with Sjögren's syndrome. Previous reports from our laboratory involving 10 patients suggested these lymphomas expressed a restricted immunoglobulin (Ig)VH gene repertoire with over use ofV1-69 gene segments. To better determine the frequency ofV1-69 use and whether there may also be selection for CDR3 structures, we sequenced the VH genes from 15 additional cases. Over half of the potentially functionalVH genes (8 of 14) used aVH1 family V1-69 gene segment, whereas the other cases used different gene segments from theVH1 (V1-46),VH3 (V3-7, V3-11, V3-30.3, V3-30.5), and VH4(V4-39) families. The 8 V1-69 VHgenes used 5 different D segments in various reading frames, but all used a J4 joining segment. The V1-69 CDR3s showed remarkable similarities in lengths (12-14 amino acids) and stretches of 2 to 3 amino acids between the V-D and D-J junctions. They did not resemble CDR3s typical of V1-69 chronic lymphocytic leukemias. This study extends our earlier work in establishing that salivary gland MALT lymphomas represent a highly selected B-cell population. Frequent use of V1-69 appears to differ from MALT lymphomas that develop at other sites. The high degree of CDR3 similarity among the V1-69cases suggests that different salivary gland lymphomas may bind similar, if not identical epitopes. Although the antigen specificities are presently unknown, similar characteristic CDR3 sequences are often seen with V1-69 encoded antibodies that have anti-IgG or rheumatoid factor activity.

Salivary gland cytokine expression in NOD and normal BALB/c mice

The autoimmune diabetes-prone nonobese diabetic (NOD) mouse develops a chronic lymphocytic infiltration of endocrine and exocrine glands. The objectives of this study were to characterize the salivary immune infiltration and cytokine expression of NOD mice and compare these findings to those of normal BALB/c mice. A decline in salivary flow rates in NOD mice began between 8 and 12 weeks of age. At this same time lymphocytic foci are detectable in the salivary glands. Lymphocytic infiltration in the salivary glands of NOD mice increased with age and simultaneously salivary function declined. No lymphocytic infiltration was seen in BALB/c salivary tissues. Messenger RNA expression of several inflammatory cytokines, including interleukin-1beta (IL-1beta), IL-2, IL-10, interferon-gamma, and tumor necrosis factor-alpha was detected in the submandibular glands of both NOD and BALB/c mice by the reverse transcription polymerase chain reaction. IL-4 synthesis was also present in some tissues. Immunohistochemical analysis demonstrated the intense expression of inflammatory cytokines within lymphocytic infiltrates and epithelial cells of all NOD mice. Minimal expression of the same cytokines was detected only occasionally in BALB/c tissues stained in parallel. These results demonstrate cytokine expression in the salivary glands of normal mice and suggest that the overexpression of these inflammatory cytokines is likely involved in the development and progression of the organ-localized autoimmunity in the salivary glands of NOD mice.

Detection of anti-Ro/SSA and anti-La/SSB autoantibody-producing cells in salivary glands from patients with Sjögren's syndrome

OBJECTIVE

To investigate and identify the presence of cells producing anti-Ro/SSA and anti-La/SSB autoantibodies in salivary glands from patients with Sjögren's syndrome (SS).

METHODS

Submucosal salivary gland biopsy samples from 10 SS patients (8 with and 2 without circulating Ro and La autoantibodies) and 14 control subjects were evaluated. Frozen tissue sections were immunostained by an avidin-biotin complex technique, using biotinylated recombinant Ro and La proteins as detection reagents. Autoantibody levels in SS patient sera were analyzed by enzyme-linked immunosorbent assay.

RESULTS

Cells producing autoantibodies to the Ro 52-kd, Ro 60-kd, and La proteins were recorded in 8, 6, and 7 of the 10 SS patient biopsy samples, respectively. Samples from the 2 SS patients without circulating Ro and La autoantibodies were negative for these autoantibody-producing cells, as were all control biopsy samples. A strong positive correlation between the presence of autoantibodies in sera and the presence of autoantibody-producing cells in glandular biopsy tissues was evident. The number of autoantibody-producing cells and the serum autoantibody levels were also correlated (r(s)=0.94, P < 0.0001).

CONCLUSION

Using a novel technique, we have demonstrated the presence of Ro and La autoantibody-producing cells in salivary gland biopsy tissues from patients with SS. These findings indicate that anti-Ro/ SSA and anti-La/SSB autoantibodies are produced and are present at sites of inflammation and indicate their potential involvement in the autoimmune exocrinopathy of this disease.

Submandibular and lacrimal gland immunoglobulin in the C3H.MRL-Faslpr autoimmune mouse model of Sjögren's syndrome

OBJECTIVE

To distinguish potential autoimmune and nonautoimmune mechanisms underlying the salivary gland inflammation seen in Sjögren's syndrome and normal aging.

STUDY DESIGN

Immunohistochemical studies were conducted on the lacrimal and salivary glands of 2- and 5-month-old C3H.MRL-Faslpr autoimmune strain mice and age-matched C3H/HeJ nonautoimmune controls.

METHODS

Glandular inflammatory foci, interstitial areas, and vasculature were stained for immunoglobulin G (IgG), immunoglobulin A (IgA), and complement to determine differences in their local immune parameter. Differences between the two strains were compared for immune changes attributable to autoimmune disease and between the two normal groups for normal aging changes.

RESULTS

Greater staining of IgG, IgA, and complement occurred in the inflammatory foci and interstitial areas of 5-month-old C3H.MRL-Faslpr lacrimal and submandibular glands compared with 5-month-old controls. Normal mice showed some increased immunoglobulin staining with aging, but little or no complement in any glands.

CONCLUSIONS

These differential findings suggest that the systemic autoimmune disease plays a more direct role in focal glandular inflammation in Sjögren's syndrome, whereas less severe immune mechanisms are involved in the inflammation of normal glands.

Young onset of primary Sjögren's syndrome: clinical and immunological characteristics

The objective of our study was to determine the clinical and immunological characteristics of primary Sjögren's syndrome (SS) in patients with a young onset of the disease. We included 144 consecutive patients (134 female and 10 male; mean age at onset 53 y; range 20-87 y) visited in our Units. All patients were white and fulfilled four or more of the diagnostic criteria for SS, proposed by the European Community Study Group in 1993. Disease onset was determined on the basis of the appearance of symptoms strongly suggestive of SS. In 13 (9%) patients, disease onset occurred before the age of 35. All were female and the disease onset occurred between 20-34 y (mean, 28 y). When compared with patients with older onset, patients with a young onset of the primary SS presented a higher prevalence of lymphadenopathy (54% vs 6%, P < 0.001), rheumatoid factor (70% vs 39%, P=0.034), anti-Ro/SS-A antibodies (70% vs 28%, P=0.004) and monoclonal immunoglobulins (23% vs 4%, P=0.02) in their sera. From the initial diagnosis of SS, three patients with a young-onset of the primary SS have developed lymphoproliferative disease at the time of the study, compared with one patient of the older-onset group (23% vs 1%, P=0.002). Our study shows several differences between younger and older onset patients, including a higher incidence of lymphomas in the younger, thus conferring to the age at onset of the disease a prognostic value.

Clonal Salivary Gland Infiltrates Associated With Myoepithelial Sialadenitis (Sjögren's Syndrome) Begin as Nonmalignant Antigen-Selected Expansions

Myoepithelial sialadenitis (MESA) is the reactive salivary gland lymphoid infiltrate that occurs in patients with Sjögren's syndrome. Although it is well established that mucosa-associated lymphoid tissue (MALT)-type lymphomas may develop from MESA, the issue of whether monoclonal B-cell populations in early MESA-associated lesions represent MALT lymphomas or more benign types of expansions has been very controversial. In addition, it is unknown whether antigen stimulation plays a role in the development or growth of MESA-associated clones. To investigate these issues, we have analyzed the Ig VH genes used by MESA-associated clones in sequential biopsies obtained from contralateral sites of seven different patients. In three cases, single clones were identified in the follow-up biopsies that were distinct from the single clones identified in the initial specimens, whereas in three other cases, the same clone was identified in both the initial and subsequent specimens. In the remaining case, two clones were identified in the second biopsy specimen, one of which was distinct from the initial clone. Of the 11 distinct clones identified in the 14 specimens that were analyzed, 8 were derived from a V1-69 VH gene segment, whereas the other 3 were derived from a V3-7 VH gene segment. In addition, the MESA clones also showed conserved amino acids sequence motifs in their third complementarity-determining regions (CDR3), some of which were encoded by N nucleotides. The marked VH gene restriction along with the similar CDR3 sequences suggests that MESA-associated clones even from different patients may bind the same or similar antigens and are selected for clonal expansion on that basis. The high rates of ongoing VH gene mutation observed in some of the cases futher suggest that the growth of early MESA clones is still dependent on antigen stimulation. In addition, our finding that different biopsies from the same patient may contain distinct clones indicates that some MESA-associated clones have not yet evolved to malignant lymphomas.

Clonal Salivary Gland Infiltrates Associated With Myoepithelial Sialadenitis (Sjögren's Syndrome) Begin as Nonmalignant Antigen-Selected Expansions

Myoepithelial sialadenitis (MESA) is the reactive salivary gland lymphoid infiltrate that occurs in patients with Sjögren's syndrome. Although it is well established that mucosa-associated lymphoid tissue (MALT)-type lymphomas may develop from MESA, the issue of whether monoclonal B-cell populations in early MESA-associated lesions represent MALT lymphomas or more benign types of expansions has been very controversial. In addition, it is unknown whether antigen stimulation plays a role in the development or growth of MESA-associated clones. To investigate these issues, we have analyzed the Ig VH genes used by MESA-associated clones in sequential biopsies obtained from contralateral sites of seven different patients. In three cases, single clones were identified in the follow-up biopsies that were distinct from the single clones identified in the initial specimens, whereas in three other cases, the same clone was identified in both the initial and subsequent specimens. In the remaining case, two clones were identified in the second biopsy specimen, one of which was distinct from the initial clone. Of the 11 distinct clones identified in the 14 specimens that were analyzed, 8 were derived from a V1-69 VH gene segment, whereas the other 3 were derived from a V3-7 VH gene segment. In addition, the MESA clones also showed conserved amino acids sequence motifs in their third complementarity-determining regions (CDR3), some of which were encoded by N nucleotides. The marked VH gene restriction along with the similar CDR3 sequences suggests that MESA-associated clones even from different patients may bind the same or similar antigens and are selected for clonal expansion on that basis. The high rates of ongoing VH gene mutation observed in some of the cases futher suggest that the growth of early MESA clones is still dependent on antigen stimulation. In addition, our finding that different biopsies from the same patient may contain distinct clones indicates that some MESA-associated clones have not yet evolved to malignant lymphomas.

Aberrant expression pattern of the SS-B/La antigen in the labial salivary glands of patients with Sjögren's syndrome

OBJECTIVE

Salivary glands of patients with Sjögren's syndrome (SS) have been shown to be a site of anti-SS-B/La antibody production. The present study investigated differences in the localization of the SS-B/La antigen in labial salivary gland (LSG) tissue between SS and non-SS patients, which may explain the local antigen-driven anti-SS-B/La response.

METHODS

Distribution of SS-B/La was studied immunohistologically in the LSG biopsy samples of 9 SS patients, 10 non-SS patients, and in normal tissues obtained at autopsy within 2 hours after death, using a mouse monoclonal antibody directed to SS-B/La. In 3 SS and 3 non-SS patients, LSGs were also studied with affinity-purified biotinylated human antibodies directed against SS-B/La.

RESULTS

In the non-SS patients, SS-B/La was primarily observed in the nucleoli of acinic cells of the LSGs. Patients with either primary SS or secondary SS showed an accumulation of SS-B/La in the nucleoplasm of acinic cells. In the SS patients, SS-B/La was also detected in the cytoplasm as a diffuse or perinuclear staining. Sometimes, SS-B/La was found along the membrane of acinic cells as well. This aberrant nuclear and cytoplasmic distribution of SS-B/La in SS patients correlated well with abnormalities in the composition of the plasma cell population in the LSGs, but not with a lymphocytic focus score > 1.

CONCLUSION

The accumulation and redistribution of SS-B/La in the LSGs may play an important role in the local antigen-driven anti-SS-B/La response in SS, and can also be used to improve the diagnostic possibilities of the LSG biopsy.

Current concepts of autoimmune exocrinopathy: immunologic mechanisms in the salivary pathology of Sjögren's syndrome

Sjögren's syndrome is a systemic autoimmune disorder characterized by symptoms of oral and ocular dryness and a chronic, progressive loss of salivary and lacrimal function. The exocrine involvement is the result of a focal, peri-ductal mononuclear cell infiltrate and the subsequent loss of secretory epithelial cells. The mechanisms of this autoimmune exocrinopathy are not understood fully. Many recent investigations have described alterations in a number of immune mediators within the salivary glands. These studies provide new insights into the immune regulation of normal salivary gland functions and the mechanisms of gland damage in Sjögren's syndrome.

The diagnosis value of beta 2-microglobulin and immunoglobulins in primary Sjögren's syndrome

Salivary and serum concentrations of beta 2-microglobulin, salivary levels of the immunoglobulins, and salivary flow (as measured by a gravimetric method) were assessed in 34 patients and 11 controls. Of the 34 study patients, 16 had a primary form of Sjögren's syndrome (pSS) and 18 had sicca syndrome. The salivary and serum concentrations of beta 2-microglobulin and salivary levels of IgA and IgG were much higher in the patients with pSS than in controls or those with sicca syndrome (p < 0.001). Similarly, the salivary IgM levels of patients with pSS were higher (although at a lower degree of statistical significance) as compared to those of patients with sicca syndrome (p < 0.01) or controls (p < 0.05). No correlation was observed among the salivary flow and the salivary IgG and IgM levels, while there was a negative relationship (p < 0.01 with salivary IgA levels in all 45 patients considered as a whole. In 12 patients with pSS, the coefficient of correlation between the salivary gland biopsy focus score and the salivary (but not serum) concentration of beta 2-microglobulin was highly significant (p < 0.001). A similar relationship was observed with the IgG (p < 0.001) and IgM (p < 0.05) levels, but not IgA. In the diagnosis of pSS, the salivary IgA level demonstrates high sensitivity and low specificity. In contrast, serum and salivary concentrations of beta 2-microglobulin, salivary IgG, and to a lesser degree, salivary IgM have high specificity and positive predictive value.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of tumor necrosis factor-alpha and interferon-gamma on the growth of a human salivary gland cell line

Interferon-gamma (IFN-gamma) is a product of activated T-lymphocytes, and tumor necrosis factor-alpha (TNF-alpha) is a product of both lymphocytes and macrophages. These cell types are often present at sites of tissue damage secondary to chronic infection or autoimmune disease. The purpose of this study was to characterize the effects of TNF-alpha and IFN-gamma on a human submandibular gland epithelial cell line (HSG). IFN-gamma caused a concentration-dependent decrease in HSG cell growth (approximately 70% in 6 days). Conversely, TNF-alpha alone had little effect on the growth of these cells. When these cytokines were added in combination (20 units/ml TNF-alpha and 1,000 units/ml of IFN-gamma), there was a synergistic antiproliferative effect; no apparent cell growth was observed. The cytokine-induced antiproliferative effect was reversible. After the apparent cessation of cell growth for 3-6 days, removal of the cytokines permitted complete growth recovery. Further, cells that recovered and exhibited growth patterns that were similar to control cells remained susceptible to the antiproliferative effects of the cytokines. Flow cytometry revealed that the percentage of cells in G0/G1 with the combination of cytokines was significantly increased by 24 h. The antiproliferative effect of IFN-gamma alone and that of IFN-gamma and TNF-alpha in combination were blocked completely using an antibody to the IFN-gamma receptor. A hypothesized mechanism of tissue damage in autoimmune inflammatory disorders is via up-regulation of cell surface markers such as intercellular adhesion molecule type I (ICAM-1) and histocompatibility antigen HLA-DR which can exacerbate the inflammatory process. Treatment of HSG cells with IFN-gamma, with or without TNF-alpha, resulted in increased levels of ICAM-1 and the acquisition of HLA-DR expression. These aggregate data suggest that IFN-gamma alone can regulate the expression of cell surface markers involved in the inflammatory process as well as cause a potent yet reversible inhibition of HSG cell growth that is modulated by the presence of TNF-alpha.

The European Community Study Group on diagnostic criteria for Sjögren's syndrome. Sensitivity and specificity of tests for ocular and oral involvement in Sjögren's syndrome

AIM

To establish a definitive set of diagnostic criteria in a multicentre European study a selected number of oral and ocular tests were performed on a large number of patients with Sjögrens Syndrome (SS) and controls. The diagnostic accuracy of each test for patients with primary and secondary SS and for controls at different ages, was studied.

METHODS

Each centre received a clinical chart describing the series of tests to be conducted. The tests included: questionnaires for dry eye and dry mouth symptoms, Schirmer's-I-test (ScT), tear fluid lactoferrin level (TFLL), break-up time (BUT) and rose Bengal score (RBS) for the eye evaluation; unstimulated and stimulated whole saliva collection (UWSC and SWSC), salivary gland scintigraphy (SGS), parotid sialography (PS) and minor salivary gland biopsy (MSGB) for oral involvement.

RESULTS

Data from 22 centres and 11 countries was collected on a total of 447 patients with SS (246 with primary SS and 201 with secondary SS) and 246 controls (of whom 113 had a connective tissue disease without SS). Among the ocular symptoms, the feeling of dry eye and 'sand in the eye' were the ones most commonly recorded in patients with SS. Similarly, the feeling of dry mouth, appearing either spontaneously or when the patient was eating or breathing, was the most frequent subjective oral symptom. Among the ocular tests, ScT showed the best balance between sensitivity and specificity (76.9% and 72.4% respectively), while RBS was the most specific test (81.7%). ScT and RBS gave also sufficiently concordant results. TFLL and BUT gave considerably less reliable results, which were not concordant with each other or with the other ocular tests. The quantitative lacrimal tests ScT and TFLL produced significantly different results in elderly controls, while RBS did not. Abnormal results for all of the ocular tests were less marked and less frequent in patients with secondary SS than in those with primary SS. The oral tests (except SWSC) were generally more reliable than the ocular tests in diagnosing SS. In particular, PS was the most specific diagnostic tools (100%), while MSGB (where the presence of at least one inflammatory focus was considered as indicative for the diagnosis) showed a good balance between sensitivity and specificity (82.4% and 86.2%, respectively). The tests showed a good degree of agreement, and, with the exception of UWSC, were not influenced by age. In the oral, as in the ocular tests, abnormal results were less frequent and less marked in patients with secondary SS.

CONCLUSIONS

The results clearly show that ScT and RBS (for the eye evaluation), and SGS, PS, MSGB and UWSC (for salivary gland involvement) are the most reliable tests for the diagnosis of SS. The clinician should be aware, however, that the test results may vary depending on the age of the patient and the type of SS (primary or secondary).

Estradiol and testosterone in minor salivary glands of Sjögren's syndrome

Nine patients with Sjögren's syndrome were studied in terms of estradiol, testosterone, and dihydrotestosterone in the labial minor salivary glands using the peroxidase-antiperoxidase method. In normal controls in women, estradiol was positive in the epithelial cells of duct, but testosterone and dihydrotestosterone were negative or doubtfully positive by case. Thus, it seems that there is a sex difference of receptors in the ductal epithelia. In the labial minor salivary glands of the patients, all estradiol, testosterone, and dihydrotestosterone were positive. As the background of Sjögren's syndrome, it seems that there is an influence of sex hormones.

Primary Sjögren's syndrome--clinical and laboratory markers of disease activity

Primary Sjögren's syndrome is a chronic autoimmune disorder of the lacrimal and salivary glands, reflecting general involvement of the exocrine tissues and leading to functional impairment. This polyglandular disease is often associated with systemic extraglandular manifestations, and laboratory tests usually indicate polyclonal B-lymphocyte hyperactivity. Clinical and laboratory markers monitoring the disease processes are needed for improved management of primary Sjögren's syndrome. However, incomplete knowledge of the long-term course of inflammation as well as of clinical manifestations makes precise and simple directions for monitoring disease activity in primary Sjögren's syndrome difficult. This review describes potential primary (eg, salivary gland histopathology, autoantibodies, soluble interleukin-2 receptors, and beta 2-microglobulin) and secondary disease activity markers (clinical and laboratory signs of glandular and extraglandular organ damage) and their known associations. The importance of genetic characteristics, patient age, and symptom duration for the disease activity markers is indicated. The systematic use of primary and secondary disease activity markers will improve our understanding of primary Sjögren's syndrome and help create better guidelines for monitoring the disease.

Quantitative immunohistologic criteria are superior to the lymphocytic focus score criterion for the diagnosis of Sjögren's syndrome

OBJECTIVE

The aim of the present study was to evaluate the diagnostic value of quantitative immunohistologic criteria for Sjögren's syndrome (SS) in labial salivary gland biopsies.

METHODS

Quantitative immunohistologic examination was performed on labial salivary gland biopsy samples from 80 healthy controls, 32 patients with primary SS, 14 patients with secondary SS, 5 with "probable" SS, 36 with keratoconjunctivitis sicca (KCS) with a lymphocytic focus score less than 1 on the lip biopsy, and 18 with rheumatoid arthritis (RA) without clinical evidence of SS.

RESULTS

This is the first study to show that immunohistologic criteria for SS, based on the percentages of IgA-containing and IgG-containing plasma cells, are able to 1) confirm the diagnosis of SS in labial salivary glands of KCS patients in the absence of grade IV lymphocytic adenitis; and 2) distinguish between a grade IV focal lymphocytic adenitis in the labial salivary glands of SS patients and of RA patients without SS.

CONCLUSION

Quantitative immunohistologic criteria were shown to be much more sensitive and disease specific than the widely accepted grade IV lymphocytic adenitis criterion, which corresponds to a lymphocytic focus score greater than 1, and these criteria should be included in the international diagnostic criteria for Sjögren's syndrome.

Follow up study of labial salivary gland lesions in primary Sjögren's syndrome

Labial salivary gland biopsy samples were taken from 27 patients with primary Sjögren's syndrome (SS), 10 with rheumatoid arthritis (RA) and secondary SS, and four normal control subjects on two occasions at intervals of more than one year. In the former group of patients, eight of the nine initially negative analyses were positive on the second sample, whereas two of the seven patients with RA and secondary SS were negative for the first sample and then positive for the second. In primary SS, the mean (SD) variation of the focus score was 1.7 (2.6) and that of salivary duct infiltration 0.2 (0.7). The former correlated well with the latter.

Increased soluble CD4 and decreased soluble CD8 molecules in patients with Sjögren's syndrome

PURPOSE

A new enzyme-linked immunosorbent assay for soluble CD4 (sCD4) and soluble CD8 (sCD8) molecules has been developed. We estimated the concentrations of these molecules in patients with Sjögren's syndrome and in patients with systemic lupus erythematosus (SLE) serving as a control population for non-Sjögren's inflammatory disease, since several findings suggestive of an aberration of immunocompetent cells have been reported in these autoimmune diseases.

PATIENTS AND METHODS

The study population consisted of 41 patients with Sjögren's syndrome (28 cases of the primary form and 13 cases of the secondary form), 66 patients with SLE, and 43 normal individuals. Serum samples and clinical and laboratory data were collected from each patient and control. Assays of the sCD4 and sCD8 molecules were performed using an enzyme-linked immunosorbent kit developed by T Cell Science Inc., Cambridge, MA.

RESULTS

The concentration of sCD4 was significantly increased in patients with both primary and secondary Sjögren's syndrome as compared with that in the control subjects. In contrast, sCD8 was significantly decreased in patients with primary disease but not in patients with secondary disease. A low or high concentration of sCD8 was significantly correlated with the presence of anti-SS-A antibody or hypocomplementemia, respectively. A similar significant correlation was noted between an increased sCD4 concentration and increased serum IgG level. In patients with SLE, the levels of both sCD4 and sCD8 were significantly increased.

CONCLUSION

These observations represent the first evidence of an increased level of the sCD4 molecule and a decreased level of the sCD8 molecule and an association with immunologic abnormalities in Sjögren's syndrome. The increased and decreased levels of these soluble molecules observed may play a pathologic role in patients with Sjögren's syndrome.

Chronic bilateral dacryo-adenitis in identical twins: a possible incomplete form of Sjögren syndrome

We report an unusual case of chronic bilateral dacryo-adenitis in 10-year-old identical twin sisters. Both girls presented with bilateral lacrimal gland enlargement and developed moderate xerophthalmia and keratitis. Both the lacrimal and minor salivary gland biopsies showed a non-granulomatous inflammatory infiltration of mono-nuclear cells. All granulomatous diseases and neoplasms could therefore be ruled out and only Sjögren syndrome and very few other forms of chronic dacryo-adenitis remained as possible diagnoses. Both patients and their parents were evaluated for auto-antibodies. Very low titres of smooth muscle antibodies were found in one, antinuclear antibodies in two and anti-dsDNA antibodies in all four members of the family. Even though the titres of antinuclear and anti-dsDNA antibodies increased in one of the sisters, both patients did not develop any sign or symptom of a systemic connective tissue disease. During the 6 years' follow up, both patients showed persistent tarsal gland enlargement but no other symptoms apart from a moderate xerophthalmia and occasional mild keratitis.

Primed and naive helper T cells in labial glands from patients with Sjogren's syndrome

This study has investigated the presence and distribution of B cells, T cells and T-cell subsets within labial glands of patients with primary Sjogren's syndrome (n = 9) and secondary Sjogren's syndrome associated with rheumatoid arthritis (n = 8) using a sequential double immunoperoxidase technique and true colour image analysis. The composition of the inflammatory infiltrates was similar in glands from both patient groups. B cells were normally present within large foci with few detected in diffuse infiltrates such that the ratio of T:B cells in foci (2.4:1) was significantly lower than in diffuse infiltrates (7.3:1; P less than 0.001). In all infiltrates helper T cells (CD8-, CD3+) predominated over suppressor/cytotoxic cells (CD8+, CD3+; 2.7:1). Analysis of primed (CD45RA-, CD45RO+) and naive (CD45RA+, CD45RO-) CD8- T cells showed that the ratio of the primed to naive subset was significantly higher in focal (4.2:1) compared to diffuse (1.5:1; P less than 0.001) areas of lymphoid infiltration. These results indicate that the focal lymphocytic infiltrates characteristic of Sjogren's syndrome contain B cells associated with a T-cell population consisting predominantly of primed CD8- helper T cells. This latter population may be responsible for upregulating glandular B-cell activity in Sjogren's syndrome.

Local IgA and IgM rheumatoid factor production in autoimmune MRL/lpr mice

Spontaneous local immunoglobulin (IgA, IgG, IgM) as well as IgA and IgM rheumatoid factor (RF) production in salivary glands, lymph nodes, and spleen was analyzed at various ages in autoimmune MRL/Mp-lpr/lpr (MRL/lpr) mice by using an ELISPOT assay. The longitudinal design of the study permitted correlations with severity of disease in salivary glands (sialadenitis). Local production of immunoglobulins in salivary glands and lymph nodes occurred with a pattern of IgG much greater than IgM greater than IgA. This isotype pattern differed from that simultaneously observed in spleen where IgG did not predominate to the same extent. Moreover, the spleen was the major site of IgM production. Rheumatoid factors constituted a significant fraction of local IgA and IgM in involved salivary glands. The pattern of IgA RF isotype expression in salivary glands contrasted with that observed in spleen. While the number of IgA and IgG secreting cells increase at an early age, the peak of RF production in salivary glands occurs in older mice. Furthermore, the level of immunoglobulin secretion was positively correlated with disease severity in salivary glands. The results suggest that local RF production is a secondary event in salivary gland inflammation in MRL/1pr mice rather than an initiating factor in this process.

The specificity of antiglobulin autoantibodies in patients with primary Sjögren's syndrome

Antiglobulin autoantibodies have already been demonstrated in the sera of patients with primary Sjögren's syndrome (primary SS). In our study, the specificity of primary SS antiglobulins for different regions of IgG molecules was examined by employing both direct binding and competitive inhibition enzyme-linked immunosorbent assay. We found that a considerable amount of total antiglobulins in primary SS was specific for the Fab portion, although the remainder was specific for the Fc portion, namely rheumatoid factor (RF). In contrast, most of the antiglobulins in RA were specific for the Fc portion of IgG. These results indicate that in primary SS, antiglobulins directed against epitopes different from those of RF are produced. These antiglobulins may prove to have a different role in primary SS than that ascribed to RF in RA.

Association of serum IgM kappa monoclonicity in patients with Sjögren's syndrome with an increased proportion of kappa positive plasma cells infiltrating the labial minor salivary glands

Minor salivary gland biopsy specimens from 11 patients with primary Sjögren's syndrome with circulating monoclonal IgM kappa cryoglobulins, seven without cryoglobulins, and four patients with rheumatoid arthritis and Sjögren's syndrome (one with monoclonal and three with polyclonal cryoglobulins) were examined by the peroxidase antiperoxidase bridge technique, using antihuman kappa and lambda antibodies. In 6/11 patients with primary Sjögren's syndrome and in one patient with Sjögren's syndrome and rheumatoid arthritis with monoclonal cryoglobulins a predominance of plasma cells containing intracytoplasmic kappa light chains was found (kappa:lambda greater than 3:1). Two of those seven patients had immunohistological features of immunocytomas. In the other five patients with circulating monoclonal cryoglobulins the kappa:lambda ratio of positive cells did not exceed 3:1, while six out of seven patients without cryoglobulins and the patients with rheumatoid arthritis and Sjögren's syndrome with polyclonal cryoglobulins had almost equal numbers of kappa and lambda stained cells. One of seven patients with primary Sjögren's syndrome without cryoglobulins had an increased number of lambda light chain positive cells, indicating a non-secretory lambda monoclonal population. These findings suggest that the main area of B cell monoclonal expansion in primary Sjögren's syndrome may be the affected exocrine glands.

Quantification of plasma cells in labial salivary glands: increased expression of IgM in Sjögren's syndrome

Plasma cells expressing IgG, IgA and IgM were quantified in labial salivary glands from patients with Sjögren's syndrome (SS) and compared with glands showing non-specific inflammatory changes and normal controls. In all glands the predominant isotype was IgA but in SS there was a significant increase in both the number and proportions of IgG and IgM positive cells (P less than 0.002). In particular, all SS cases contained greater than 10% IgM positive cells (mean = 26.8 +/- 15.5). The results suggest that accumulation of IgM positive plasma cells may be a specific finding in SS and support the concept that the glandular lesions may be a site of B-cell clonal expansion. Since most B-cell hyperproliferative states in SS, including lymphoma, are associated with synthesis of IgM simple quantification of plasma cells may have important diagnostic and prognostic significance.

A new and highly sensitive immunohistologic diagnostic criterion for Sjögren's syndrome

Immunohistologic investigation of the sublabial salivary glands of 65 surgical patients who were free of systemic disease (control) and 19 patients with Sjögren's syndrome resulted in a new diagnostic criterion for SS that was more disease-specific than the widely used lymphocytic focus score criterion. Our bivariate classification criterion, which is based on the percentages of IgA- and IgG-containing plasma cells, has a specificity of 95.4% and a sensitivity of 100%, while its overall percentage of misclassification is 3.6%. This immunohistologic diagnostic criterion results in a reduction of the percentage of false-positive diagnoses from 9% to 4.6%.

Sialochemistry in Sjögren's syndrome: a review

Sjögren's syndrome (SS) is an autoimmune exocrinopathy. The salivary glands are the site of activated T- and B-lymphocytes, along with gradual parenchymal destruction, diminished flow and altered composition of the secretory product. At present, sialochemistry has achieved no significance for the evaluation of SS patient. However, the number of sialochemical publications is steadily growing. This study review current sialochemical findings in patients with SS and relate the observations to the present concept of diagnosis, pathogenesis and prognosis of SS. An ideal combination of the collection of low-stimulated pure secretion, measurements of absolute flow-rates, and biopsy from the same glands seem to be unobtainable in SS patients. But two procedures may be appropriate: stimulated parotid secretion combined with parotid biopsies, or absorbance of low-stimulated labila saliva combined with labial gland biopsy. Sufficient data on disease-specific alterations in salivary composition in SS are still lacking. However, detection of specific changes in protein synthesis or in glycosylation as well as the detection of inflammatory cell products should be possible with the use of sensitive biochemical assays.

Lacrimal and salivary immunoglobulins in Sjögren's syndrome

The diagnosis of Sjögren's syndrome is sometimes difficult. We have previously demonstrated the diagnostic value of salivary immunoglobulins IgG and IgM in Sjögren's syndrome. In the present study, we assessed both lacrimal immunoglobulins (1 Ig) and salivary Ig (s Ig) in Sjögren's syndrome. We studied 112 patients: 71 had rheumatoid arthritis (57 sero positive), 19 had connective tissue diseases or vasculitis (six Sjögren's syndrome alone, six systemic sclerosis, three mixed connective tissue diseases, three polyarteritis, one relapsing polychondritis), and 22 patients had other inflammatory, metabolic or degenerative joint diseases. Lacrimal Ig and salivary Ig were assessed by double immunodiffusion with antisera specific for IgG, IgM and IgA. Each Ig class was scored on a scale ranging from 0 to 3 plus without knowledge of the patient's diagnosis. The results of factorial analysis demonstrated a strong relationship between xerophtalmia, positive Schirmer's test, s IgG, s IgM, 1 IgG, and 1 IgM in patients with seropositive rheumatoid arthritis or other connective tissue diseases. Analysis of individual parameters showed a significant relationship between 1 IgG and ocular complaints (P less than 0.01), positive Schirmer's test (P less than 0.05), positive rose bengal dye test (P less than 0.05), 1 IgM (P less than 0.01), s IgG (P less than 0.01) and s IgM (P less than 0.05). A significant relationship was also found between s IgG and ocular complaints (P less than 0.02), positive rose bengal dye test (P less than 0.01), positive minor salivary gland biopsy (P less than 0.05), s IgM (P less than 0.01), and 1 IgM (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibody synthesis in salivary glands of Sjögren's syndrome patients

We investigated the possibility that autoantibodies are locally synthesized and secreted within salivary glands of patients with Sjögren's syndrome by measuring specific autoantibody as a proportion of the total immunoglobulin present both in serum and saliva. Of 25 patients studied, 21 showed salivary enrichment of IgA anti-La, in three cases IgA anti-La being detected in saliva when IgG anti-La was negative (by ELISA) in serum. Twenty-four showed enrichment of salivary rheumatoid factors and IgA and/or IgM carrying the 17-109 idiotype, a marker of kappa IIIb light chains. These data suggest that autoantibodies, especially of the IgA class, are synthesized primarily in salivary gland and that they can be detected in saliva before they become apparent in the peripheral circulation. The subsequent deposition of these antibodies within salivary glands may be a contributory factor to the pathogenesis of Sjögren's syndrome.

The expression and function of CD3 and CD5 in patients with primary Sjögren's syndrome

We studied the expression and function of 2 cell surface markers that induce T cell activation, CD3 and CD5, in 19 patients with primary Sjögren's syndrome (SS). The expression of CD3+ lymphocytes was normal, but CD3 function was moderately reduced, as measured by anti-CD3-induced T cell proliferation. Anti-CD3-induced stimulation of T cell help for Ig production and non-major histocompatibility complex-restricted (natural) killing were normal. In contrast, there was reduced expression and function of the CD5 molecule on peripheral blood lymphocytes of the SS patients. The ratio of CD5+ to CD3+ lymphocytes was 0.45 in SS patients compared with 0.85 in normal subjects, indicating that the CD3+ cells are relatively CD5-deficient in SS patients. Anti-CD5 monoclonal antibody did not augment suboptimal anti-CD3 stimulation of whole peripheral blood lymphocytes or of purified T lymphocytes from SS patients, which indicated impaired functioning of the CD5 molecule. A significant impairment in proliferation was found in response to phorbol myristate acetate and to ionomycin in combination, suggesting defective intracellular signaling. Findings from serial studies of individual patients suggested that normal or low expression of CD5 on T cells can be stable over periods as long as 2 years. However, in 2 patients who required systemic therapy, a correction of the CD5 lymphocyte abnormality occurred in association with clinical remission, which suggests the potential reversibility of this condition. Our findings suggest a possible defect in intracellular signaling in primary SS, related in part to the CD5 molecule, which may provide a molecular explanation for the T cell hyporesponsiveness that is characteristic of this disease.