Presence of intraepithelial B-lymphocytes is associated with the formation of lymphoepithelial lesions in salivary glands of primary Sjögren's syndrome patients.

OBJECTIVES: Lymphoepithelial lesions (LELs) in salivary glands are associated with primary Sjögren's syndrome (pSS). LELs are composed of hyperplastic epithelium infiltrated with lymphocytes. The objective of this study was obtaining insight in the relative roles of intraepithelial B- and T-lymphocytes in the formation of LELs in salivary glands of pSS patients. METHODS: Parotid and labial salivary gland biopsies of pSS patients (n=15), non-SS sicca patients (n=5) and non-sicca controls (n=5) were analysed. Serial sections were stained with H & E and for cytokeratin, CD20 and CD3. Striated ducts with lymphocytes, but without hyperplasia, and striated ducts with LELs were identified in H & E and cytokeratin stained sections. LELs were classified in successive stages of severity based on the amount of hyperplasia (stage1-3). Numbers of B- and T-lymphocytes within striated ducts and LELs were counted in CD20 and CD3 stained sections. RESULTS: Lymphocyte-containing striated ducts of both salivary glands of all pSS and control patients harboured T-lymphocytes, scattered throughout the ductal epithelium. In contrast, B-lymphocytes were exclusively found in a small fraction (21%) of striated ducts without hyperplasia and in nearly all striated ducts with LELs of pSS patients, but not in controls. In striated ducts with LELs B-lymphocytes were mostly located in the areas of proliferating epithelium. Numbers of B-lymphocytes and B/T-ratios increased significantly with higher severity of LELs. This was even more pronounced in the parotid than in the labial gland. CONCLUSIONS: We conclude there is an association between presence of intraepithelial B-lymphocytes and the formation of LELs in salivary glands of pSS patients.

Submandibular gland-specific inflammaging-induced hyposalivation in the male senescence-accelerated mouse prone -1 line (SAM-P1).

Aging has pronounced effects on mammalian tissues and cells, but the impacts of aging on salivary gland function are relatively unknown. This study aims to evaluate the effects of aging on submandibular gland (SMG) and parotid gland (PG) functions in the male senescence-accelerated mouse. In vivo analysis at the systemic level revealed that salivary secretion induced by pilocarpine, a muscarinic agonist, from the SMG was significantly decreased in aged mice, whereas salivary secretion from the PG was not affected. To evaluate organ-level function, the SMG was perfused with the muscarinic agonists carbachol and calcium ionophore A23187 ex vivo to induce salivary secretion, and decreased saliva production was also observed in the aged SMG. Histological analysis revealed the presence of CD4-positive lymphocytes infiltrating the aged SMG. Furthermore, real-time PCR revealed that the aged SMG exhibited accelerated cell aging, increased levels of the inflammatory cytokine interleukin-6, and decreased mRNA levels of the water channel protein aquaporin-5 (AQP5). In summary, these results demonstrate that SMG function in aged mice was diminished, and that cell senescence, chronic inflammation, and the decreased gene expression of AQP5 are the likely causes of hyposalivation in the SMG of aged mice.

Salivary Gland Stem Cells Age Prematurely in Primary Sjögren's Syndrome.

OBJECTIVE: A major characteristic of the autoimmune disease primary Sjögren's syndrome (SS) is salivary gland (SG) hypofunction. The inability of resident SG stem cells (SGSCs) to maintain homeostasis and saliva production has never been explained and limits our comprehension of mechanisms underlying primary SS. The present study was undertaken to investigate the role of salivary gland stem cells in hyposalivation in primary SS. METHODS: SGSCs were isolated from parotid biopsy samples from controls and patients classified as having primary SS or incomplete primary SS, according to the American College of Rheumatology/European League Against Rheumatism criteria. Self-renewal and differentiation assays were used to determine SGSC regenerative potential, RNA was extracted for sequencing analysis, single telomere length analysis was conducted to determine telomere length, and frozen tissue samples were used for immunohistochemical analysis. RESULTS: SGSCs isolated from primary SS parotid gland biopsy samples were regeneratively inferior to healthy control specimens. We demonstrated that SGSCs from samples from patients with primary SS are not only lower in number and less able to differentiate, but are likely to be senescent, as revealed by telomere length analysis, RNA sequencing, and immunostaining. We further found that SGSCs exposed to primary SS-associated proinflammatory cytokines we induced to proliferate, express senescence-associated genes, and subsequently differentiate into intercalated duct cells. We also localized p16+ senescent cells to the intercalated ducts in primary SS SG tissue, suggesting a block in SGSC differentiation into acinar cells. CONCLUSION: This study represents the first characterization of SGSCs in primary SS, and also the first demonstration of a linkage between an autoimmune disease and a parenchymal premature-aging phenotype. The knowledge garnered in this study indicates that disease-modifying antirheumatic drugs used to treat primary SS are not likely to restore saliva production, and should be supplemented with fresh SGSCs to recover saliva production.

The correlation of immunologic derangement and juvenile recurrent parotitis: an investigation of the laboratory immunological observation.

BACKGROUND: Juvenile recurrent parotitis (JRP) is defined as recurrent parotid inflammation, generally associated with nonobstructive sialectasis of the parotid gland. In addition, the etiology remains unclear, probably immunologically mediated. AIM: The purposes of the present study were to report the relationship between JRP and immune function from the measurement of the JRP patients' immunoglobulins and T-lymphocyte subset. METHODS: Immunologic assay from 2014 to 2017 of 100 children diagnosed with JRP at Shanghai Ninth Hospital compared with the 100 normal children by age. RESULTS: The CD4 level of JRP children aged >6 years was significant lower than the one of JRP preschool children (p < .05), while the IgG level was significant higher than the one of the JRP preschool children (p < .05). In comparison with the normal children, the value of CD8 T cells, immunoglobulin G (IgG), immunoglobulin E (IgE), immunoglobulin A (IgA) and C3 (p < .01) of JRP children was significant higher, while the value of CD4 T cells was lower (p < .01) in spite of age. What is more, the value of CD8 T cells of JRP preschool children was much significant higher than the one of the normal preschool children (p < .01). CONCLUSION: The immune function of JRP patients may become disorder: the suppression cellular immune function and inadequate humoral immune expression.

Abatacept treatment of patients with primary Sjögren's syndrome results in a decrease of germinal centres in salivary gland tissue.

OBJECTIVES: The aim of this study was to assess the histopathological changes in parotid gland tissue of primary Sjögren's syndrome (pSS) patients treated with abatacept. METHODS: In all 15 pSS patients included in the open-label Active Sjögren Abatacept Pilot (ASAP, 8 abatacept infusions) study parotid gland biopsies were taken before treatment and at 24 weeks of follow up. Biopsies were analysed for pSS-related histopathological features and placed in context of clini- cal responsiveness as assessed with EULAR Sjögren's syndrome disease activity index (ESSDAI). RESULTS: Abatacept treatment resulted in a decrease of germinal centres (GCs)/ mm2 (p=0.173). Number of GCs/mm2 at baseline was associated with response in the glandular domain of ESSDAI (Spearman ρ=0.644, p=0.009). Abatacept treatment did not reduce focus score, lymphoepithelial lesions, area of lymphocytic infiltrate, amount of CD21+ networks of follicular dendritic cells, and numbers of CD3+ T-cells or CD20+ B- cells. Number of IgM plasma cells/mm2 increased (p=0.041), while numbers of IgA and IgG plasma cells/mm2 were unaffected during abatacept treatment. CONCLUSIONS: Abatacept affects formation of GCs of pSS patients in parotid glands, which is dependent on co-stimulation of activated follicular-helper-T-cells. Herewith, local formation of (autoreactive) memory B-cells is inhibited. Presence of GCs at baseline predicts responsiveness to abatacept in the ESSDAI glandular domain.

Ultrasonographic Features of Immunoglobulin G4-Related Sialadenitis.

The aim of this study was to determine the role of ultrasonography in the diagnosis and follow-up evaluation of immunoglobulin G4-related sialadenitis. In this study, 42 patients with immunoglobulin G4-related sialadenitis underwent ultrasonography of the parotid and submandibular glands, and the sonographic appearance was compared with the pathologic findings. Post-treatment ultrasonographic appearance was compared with the pre-treatment findings in 30 patients who received immunomodulatory therapy. The ultrasonographic appearance of the affected glands was divided into five patterns: superficial hypo-echoic, multiple hypo-echoic foci, whole-gland heterogeneity, space occupying and normal echo. Histopathologic examination revealed marked lymphoplasmacytic inflammation and inter-lobular fibrosis, which were more severe in the superficial than deep portion of the affected glands. After treatment, the volume of the affected gland decreased significantly, the internal echo became more homogeneous and the superficial hypo-echoic area disappeared or was reduced. In conclusion, ultrasonography may play an important role in the diagnosis and follow-up evaluation of immunoglobulin G4-related sialadenitis.

Despite sequence homologies to gluten, salivary proline-rich proteins do not elicit immune responses central to the pathogenesis of celiac disease.

Celiac disease (CD) is an inflammatory disorder triggered by ingested gluten, causing immune-mediated damage to the small-intestinal mucosa. Gluten proteins are strikingly similar in amino acid composition and sequence to proline-rich proteins (PRPs) in human saliva. On the basis of this feature and their shared destination in the gastrointestinal tract, we hypothesized that salivary PRPs may modulate gluten-mediated immune responses in CD. Parotid salivary secretions were collected from CD patients, refractory CD patients, non-CD patients with functional gastrointestinal complaints, and healthy controls. Structural similarities of PRPs with gluten were probed with anti-gliadin antibodies. Immune responses to PRPs were investigated toward CD patient-derived peripheral blood mononuclear cells and in a humanized transgenic HLA-DQ2/DQ8 mouse model for CD. Anti-gliadin antibodies weakly cross-reacted with the abundant salivary amylase but not with PRPs. Likewise, the R5 antibody, recognizing potential antigenic gluten epitopes, showed negligible reactivity to salivary proteins from all groups. Inflammatory responses in peripheral blood mononuclear cells were provoked by gliadins whereas responses to PRPs were similar to control levels, and PRPs did not compete with gliadins in immune stimulation. In vivo, PRP peptides were well tolerated and nonimmunogenic in the transgenic HLA-DQ2/DQ8 mouse model. Collectively, although structurally similar to dietary gluten, salivary PRPs were nonimmunogenic in CD patients and in a transgenic HLA-DQ2/DQ8 mouse model for CD. It is possible that salivary PRPs play a role in tolerance induction to gluten early in life. Deciphering the structural basis for the lack of immunogenicity of salivary PRPs may further our understanding of the toxicity of gluten.

Effect of low-level laser therapy on irradiated parotid glands--study in mice.

The objective of this study was to evaluate the effect of low-level laser therapy (LLLT) on radiotherapy-induced morphological changes and caspase-3 immunodetection in parotids of mice. Forty-one Swiss mice were divided into control, radiotherapy, 2- and 4-J laser groups. The experimental groups were exposed to ionizing radiation in a single session of 10 Gy. In the laser groups, a GaAlAs laser (830 nm, 100 mW, 0.028 cm2, 3.57 W/cm2) was used on the region corresponding to the parotid glands, with 2-J energy (20 s, 71 J/cm2) or 4 J (40 s, 135 J/cm2) per point. LLLT was performed immediately before and 24 h after radiotherapy. One point was applied in each parotid gland. The animals were euthanized 48 h or 7 days after radiotherapy and parotid glands were dissected for morphological analysis and immunodetection of caspase-3. There was no significant difference between groups in the immunodetection of caspase-3, but the laser groups had a lower percentage compared to the radiotherapy group. LLLT promoted the preservation of acinar structure, reduced the occurrence of vacuolation, and stimulated parotid gland vascularization. Of the two LLLT protocols, the one using 4 J of energy showed better results.

[STUDY OF SAFETY OF PAROTITIS VACCINE].

AIM: Monitoring of post-vaccinal complications in children immunized with a parotitis vaccine. MATERIALS AND METHODS: Observation of 198 945 children, immunized with 16 lots of parotitis vaccine with Leningrad-3 strain (L-3), was carried out for 3 years. Paired samples of sera and saliva were obtained from children, in whom adverse events were registered for 42 days after vaccination. Titers of specific IgM and IgG were determined in blood sera. Analysis of nucleotide sequences of genes F, SH and NH of RNA of parotitis virus was carried out from samples of blood and saliva. RESULTS: Intensive parameter of vaccine-associated aseptic meningitis under the conditions of the experiments was 0 for 100 000 immunized. Frequency of occurrence of post-vaccinal parotitis was 0.06% from the number of vaccinated--18 cases of vaccine-associated parotitis were registered and laboratory confirmed. A significant difference in specific activity was detected for 3 lots of the vaccine, that were associated with cases of development of parotitis, relative to that of 13 lots of vaccine, development of parotitis was not registered after administration of those. CONCLUSION: The study carried out confirmed low neurovirulence of the parotitis vaccine with the L-3 strain of parotitis virus, as well as a low degree of its reactogenicity. A relatively high immunization dose of the used vaccine could be one of the reasons of development of post-vaccinal complications in part of the immunized children.

Passive transfer of antibodies to the linear epitope 60 kD Ro 273-289 induces features of Sjögren's syndrome in naive mice.

Sjögren's syndrome (SS) is an autoimmune inflammatory disease that primarily affects the lacrimal and salivary glands causing dry eyes and mouth. Antibodies to Ro60 are observed frequently in patients with SS; however, the role of these antibodies in SS initiation and progression remains unclear. The sequence Ro60 273-289 (Ro274) is a known B cell epitope of Ro60 and antibodies to this epitope have been observed in a subset of SS patients and in animals immunized with Ro60 protein. Animals immunized with Ro274 linear peptide develop a Sjögren's-like illness. We hypothesized that passive transfer of anti-Ro274-specific immunoglobulin (Ig)G would induce a Sjögren's-like phenotype. To evaluate this hypothesis, we adoptively transferred affinity-purified Ro274 antibodies into naive BALB/c animals, then evaluated salivary gland histology, function and IgG localization 4 days post-transfer. At this time-point, there was no demonstrable mononuclear cell infiltration and salivary glands were histologically normal, but we observed a functional deficit in stimulated salivary flow of animals receiving Ro274 antibodies compared to animals receiving control IgG. Cellular fractionation and enzyme-linked immunosorbent assay revealed Ro274-specific antibodies in the nucleus and cytoplasmic fractions of isolated parotid salivary gland cells that was confirmed by immunohistochemistry. These data support the hypothesis that antibodies to Ro274 deposit in salivary glands can enter intact salivary gland cells and are involved in the dysregulation of salivary flow in SS.

Ig gene analysis reveals altered selective pressures on Ig-producing cells in parotid glands of primary Sjögren's syndrome patients.

In this study, we sought to understand the selective pressures shaping the Ig-producing cell repertoire in the parotid glands of primary Sjögren's syndrome (pSS) patients before and after rituximab treatment (RTX). In particular, we evaluated the role of potential N-glycosylation motifs acquired by somatic hypermutation (ac-Nglycs) within Ig H chain V region (IGHV) genes as alternative selective pressures for B cells in pSS. Five pSS patients received RTX. Sequential parotid salivary gland biopsies were taken before RTX, at 12 wk and at 36-52 wk after treatment. Parotid biopsies from four non-pSS patients served as controls. Sequence analysis was carried out on the IgA and IgG RNA transcripts expressing IGHV3 genes in all parotid biopsies. Both IgG and IgA sequences from pSS patients exhibited no evidence for positive Ag-driven selection pressure in their CDRs in contrast to non-pSS controls. The prevalence of IgG sequences with ac-Nglycs was significantly higher in pSS patients than in non-pSS controls. Selection pressures shaping the IgG and IgA repertoire within pSS patients' parotid glands are distinct from those in non-pSS controls, with very little evidence for positive (auto)antigen selection. The higher prevalence of ac-Nglycs on pSS-IgG compared with non-pSS IgG indicates that ac-Nglycs could be an alternative form of selection pressure. We speculate that B cell hyperproliferation within parotid glands of pSS patients may result from Ag-independent interactions such as that between glycosylated B cell receptors and lectins within the microenvironment rather than (auto)antigen-specific stimulation. Our study brings a new perspective into research on pSS.

Prominent mucoid degeneration of the parotid gland in a patient with systemic lupus erythematosus.

Lupus erythematosus (LE) can cause various cutaneous lesions including panniculitis (LE profundus), but salivary gland involvement has been extremely rare in patients with LE. Herein, we report the first documented case of systemic LE with prominent mucoid degeneration and lymphoplasmacytic infiltration in the parotid gland. A 38-year-old Japanese male with histories of autoimmune hemolytic anemia and systemic LE presented with a swelling of the bilateral cervical region. A physical examination revealed a swelling of the bilateral parotid gland and erythema of the right cheek. A biopsy specimen of the cheek demonstrated LE profundus with mucoid material deposition in the dermis. A biopsy specimen of the parotid gland showed lymphoplasmacytic infiltration and prominent mucoid material deposition within the parotid gland as well as mild lymphoplasmacytic infiltration and hyaline fat necrosis in the perisalivary tissue. Mucoid material deposition is one of the characteristic features of LE, however, this is the first case demonstrating mucoid material deposition in the salivary gland. Moreover, albeit extremely rare, lymphoplasmacytic infiltration within the lobules of the salivary gland has also been reported in patients with LE. Therefore, it is important that both lymphoplasmacytic infiltration and mucoid material deposition must be included in the differential diagnostic considerations for salivary gland tumors in patients who had been previously diagnosed as systemic or discoid LE.

Different stages of primary Sjogren's syndrome involving lymphotoxin and type 1 IFN.

Primary Sjögren's syndrome (pSS) is a complex autoimmune disease starting in the salivary and lacrimal glands and continuing to involve the lungs and kidneys with the eventual development of lymphoma. Many studies have emphasized the role of type 1 IFN (IFN-α) and lymphotoxin α (LTα) in the pathogenesis of the disease. The present studies were designed to delineate the role of IFN-α in pSS using an animal model, the IL-14α (IL14αTG) transgenic mouse. IL14αTG mice lacking the type 1 IFNR (IL14αTG.IFNR(-/-)) had the same submandibular gland and lacrimal gland injury as did the IL14αTG mice, but they lacked the later parotid gland and lung injury. Development of lymphoma was delayed in IL14αTG.IFNR(-/-) mice. The switch from IgM to IgG autoantibodies as well as the increase in serum IgG2a seen is IL14αTG mice was inhibited in IL14αTG.IFNR(-/-) mice. Production of LTα was identified in both IL14αTG mice and IL14αTG.IFNR(-/-) mice at the time that salivary gland injury was occurring. These and previous studies suggest a model for pSS that separates the disease into several stages: 1) initial injury to the submandibular and lacrimal glands via an environmental insult and LTα; 2) amplification of local injury via the production of type 1 IFN; injury to the parotid glands, lungs, and kidneys is seen; 3) progression of systemic inflammation with the eventual development of large B cell lymphoma. Understanding these different stages will help to develop strategies for treatment of patients with pSS based on the status of their disease.

Vaccine-related mumps infections in Thailand and the identification of a novel mutation in the mumps fusion protein.

An outbreak of nine cases of mumps was reported from a total of 97 vaccinated nursing students at two medical colleges in Thailand in 2010, 16-26 days after administration of MMR vaccine containing the L-Zagreb mumps strain. Symptoms ranged in severity from fever and parotid swelling to orchitis. Clinical samples were obtained from seven patients and three were suitable for further study. Sequencing confirmed that the SH gene of the mumps virus in the unpassaged clinical specimens was identical to the L-Zagreb SH gene in the vaccine. Further analysis of the viral genome identified nucleotide position 5170 as a novel mutation which corresponds to an amino acid change in the fusion protein. This study provides another virologically confirmed example of mumps resulting from the L-Zagreb vaccine strain.

Persistence of immunoglobulin-producing cells in parotid salivary glands of patients with primary Sjögren's syndrome after B cell depletion therapy.

OBJECTIVES: To assess the persistence of immunoglobulin-producing cell populations in the parotid salivary glands of patients with primary Sjögren's syndrome (pSS) after B cell depletion therapy with rituximab. METHODS: Thirteen patients with pSS and four control patients were included in this study. Patients with pSS were treated with rituximab or placebo. Sequence analysis was carried out on IgA- and IgG-encoding transcripts extracted from parotid salivary gland biopsy specimens taken before treatment and at 12-16 and 36-52 weeks after treatment. RESULTS: At baseline, many clonally related sequences were seen in patients with pSS. The number of clonal expansions was significantly higher in patients with pSS than in control patients. Clonal expansions were composed of IgA- and/or IgG-expressing cells. Rituximab did not significantly alter the degree of clonal expansions. Groups of clonally related cells had members which were shared between biopsy specimens taken before and after treatment. Mutation frequencies of immunoglobulin sequences from clonally related cells in patients with pSS were higher after treatment. CONCLUSIONS: Rituximab treatment does not alter the characteristic features of increased clonal expansions seen in the parotid salivary glands of patients with pSS. The presence of clonally related immunoglobulin-producing cells before and after rituximab treatment strongly suggests that immunoglobulin-producing cells persist in salivary glands of patients with pSS despite B cell depletion. The presence of mixed isotype expression within groups of clonally related cells indicates local class switching in salivary glands of patients with pSS. Persistent immunoglobulin-producing cells may underlie disease relapse after treatment.

Wegener's granulomatosis of the major salivary glands.

Wegener's granulomatosis is one of the anti-cytoplasmic autoantibodies (ANCA)-associated vasculitides. Although it typically affects the lungs and kidneys, the head and neck are also involved in most cases but the site usually affected is the upper airway. However, there are 35 cases with well-documented clinicopathological data in which Wegener's granulomatosis manifested in the major salivary glands, most commonly the parotid. Twenty-four patients presented with salivary signs and symptoms, in eight of whom there was no other presenting manifestation. These signs and symptoms may mimic infection or neoplasia and laboratory investigations, including ANCA serology and histopathology, may be non-specific; thus, in 21 of the 35 patients (60%) there was a delay in diagnosis. Amongst the 21 were 11 of the 14 (78.6%) patients who presented with unilateral parotid disease and three of the five who died. Three other patients suffered permanent pulmonary, two renal and five facial nerve damage. This article reviews the literature on major salivary gland involvement in Wegener's granulomatosis, which should be considered in the differential diagnosis of major salivary gland disease particularly if commoner causes have been excluded. A detailed medical history, and persistently inconclusive laboratory tests, could provide the clues that enable prompt diagnosis.