Destruction Of Exocrine Glands Research Articles

Increased expression of CXCL10 and CCL3 salivary gland chemokines in primary Sjögren's syndrome detected and systematically quantified using novel RNAscope® in situ hybridisation.

Primary Sjogren's syndrome is a chronic inflammatory disease characterised by the destruction of exocrine glands. We have previously shown significantly upregulated levels of CXCL10 and CCL3 chemokines in saliva from Sjogren's syndrome patients. In this study, we examined the expression pattern and localisation of these chemokines at the site of inflammation in patients' minor salivary glands using novel RNAscope® in situ hybridisation. Minor salivary glands from 33 primary Sjogren's syndrome patients and 22 non-Sjogren's syndrome sicca controls were included. The biopsies were formalin- fixed, paraffin-embedded and histopathologically evaluated. The CXCL10 and CCL3 mRNA expression in the glandular tissue was investigated using reverse transcription quantitative real-time polymerase chain reaction followed by RNAscope® in situ hybridisation. The mRNA expression of CXCL10 was higher than CCL3 in all patients. Significantly elevated expression of CXCL10 and CCL3 was detected in patients that also expressed autoantibody positivity and a positive biopsy for mononuclear cell infiltrates when compared to controls. CXCL10 was localised as clusters within focal infiltrates as well as adjacent to acinar and ductal epithelium, while CCL3 was expressed as scattered single mRNA molecules in focal infiltrates and in acinar cells. Our findings suggest CXCL10 as a possible disease biomarker in primary Sjogren's syndrome due to its upregulated expression in both saliva and minor salivary glands of patients and the localisation in the tissue. This should be re-assessed in a larger primary Sjogren's syndrome patient cohort, followed by additional functional studies to further validate its potential as a disease biomarker.

Cell therapy in Sjögren's syndrome: opportunities and challenges.

Sjögren's syndrome (SS) is a chronic autoimmune disease caused by immune system disorders. The main clinical manifestations of SS are dry mouth and eyes caused by the destruction of exocrine glands, such as the salivary and lacrimal glands, and systemic manifestations, such as interstitial pneumonia, interstitial nephritis and vasculitis. The pathogenesis of this condition is complex. However, this has not been fully elucidated. Treatment mainly consists of glucocorticoids, disease-modifying antirheumatic drugs and biological agents, which can only control inflammation but not repair the tissue. Therefore, identifying methods to regulate immune disorders and repair damaged tissues is imperative. Cell therapy involves the transplantation of autologous or allogeneic normal or bioengineered cells into the body of a patient to replace damaged cells or achieve a stronger immunomodulatory capacity to cure diseases, mainly including stem cell therapy and immune cell therapy. Cell therapy can reduce inflammation, relieve symptoms and promote tissue repair and regeneration of exocrine glands such as the salivary glands. It has broad application prospects and may become a new treatment strategy for patients with SS. However, there are various challenges in cell preparation, culture, storage and transportation. This article reviews the research status and prospects of cell therapies for SS.

Association of Inflammatory Cytokine Levels with Extra Glandular Manifestations, Fatigue, and Disease Activity in Primary Sjögren's Syndrome in Saudi Patients: A Cross-Sectional Study.

Primary Sjögren's syndrome (pSS) is an autoimmune disease that can cause fatigue and extraglandular manifestations (EGMs). pSS is associated with cytokine network dysregulation, which may be related to the immune-mediated destruction of exocrine glands. We determined cytokine levels and their relationship to EGMs, the European League Against Rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI), and fatigue in Saudi patients with pSS. This study was a cross-sectional, single-center study. We included forty-one patients and 71 controls. Serum samples were collected from random healthy people and pSS patients who were followed in the rheumatology and pulmonary clinics of King Saud University Medical City in Riyadh, Saudi Arabia. Levels of the frequently studied cytokines were measured using Luminex xMAP technology. Each ESSDAI score and EGM were recorded, and the Arabic version of the fatigue severity scale (FSS) was applied to assess fatigue. The main outcome measures were cytokine levels in pSS Saudi patients using/not using immune-suppressive medications (ISMs). Thirty-six (87.8%) patients had one or more EGMs, and the mean ESSDAI score was 9.95 ± 7.73. There was a significant decrease in TNFα and IL-21 levels in the pSS group compared to those in the control group (p = 0.034 and p < 0.001, respectively), whereas IL-12 levels were significantly elevated in the pSS group (p = 0.002). Cytokine levels in patients who used ISMs were the same as those in patients who did not use medications. Decreased IL-1β (p = 0.014), IL-2 (p = 0.035), IL-6 (p = 0.014), and IL-35 (p = 0.010) levels were observed in patients who had EGMs. Patients who had low disease activity exhibited low IL-10 (p = 0.018) and high IFN-α (p = 0.049), IFN-β (p = 0.049), IL-1β (p = 0.006), and IL-35 (p = 0.032) levels compared to patients with high disease activity. A negative association between a positive fatigue score and IL-1β (p = 0.010), IL-2 (p = 0.037), IFN-α (p = 0.025), TNFα (p = 0.030), IL-17 (p = 0.029), IL-12 (p = 0.046), and IL-21 (p = 0.005) levels was found. Cytokine profiles correlate with EGMs, ESSDAI, and fatigue. Patients with controlled disease activity have a normal cytokine profile that is similar to that of controls.

Single-cell profiling reveals pathogenic role and differentiation trajectory of granzyme K+CD8+ T cells in primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is a systemic autoimmune inflammatory disease mainly defined by T cell-dominated destruction of exocrine glands. Currently, CD8+ T cells are thought to be involved in the pathogenesis of pSS. However, the single-cell immune profiling of pSS and molecular signatures of pathogenic CD8+ T cells have not been well elucidated. Our multiomics investigation showed that both T cells and B cells, especially CD8+ T cells, were undergoing significant clonal expansion in pSS patients. TCR clonality analysis revealed that peripheral blood granzyme K+ (GZMK+) CXCR6+CD8+ T cells had higher a proportion of clones shared with CD69+CD103-CD8+ tissue-resident memory T (Trm) cells in labial glands in pSS. CD69+CD103-CD8+ Trm cells featured by high expression of GZMK were more active and cytotoxic in pSS compared with their CD103+ counterparts. Peripheral blood GZMK+CXCR6+CD8+ T cells with higher CD122 expression were increased and harbored a gene signature similar to Trm cells in pSS. Consistently, IL-15 was significantly elevated in pSS plasma and showed the capacity to promote differentiation of CD8+ T cells into GZMK+CXCR6+CD8+ T cells in a STAT5-dependent manner. In summary, we depicted the immune profile of pSS and further conducted comprehensive bioinformatics analysis and in vitro experimental investigations to characterize the pathogenic role and differentiation trajectory of CD8+ Trm cells in pSS.

Immunomodulatory effects of umbilical mesenchymal stem cell-derived exosomes on CD4+ T cells in patients with primary Sjögren's syndrome

BackgroundPrimary Sjögren's syndrome (pSS) is an autoimmune disease that leads to the destruction of exocrine glands and multisystem lesions. Abnormal proliferation, apoptosis, and differentiation of CD4+ T cells are key factors in the pathogenesis of pSS. Autophagy is one of the important mechanisms to maintain immune homeostasis and function of CD4+ T cells. Human umbilical cord mesenchymal stem cell-derived exosomes (UCMSC-Exos) may simulate the immunoregulation of MSCs while avoiding the risks of MSCs treatment. However, whether UCMSC-Exos can regulate the functions of CD4+ T cells in pSS, and whether the effects via the autophagy pathway remains unclear.MethodsThe study analyzed retrospectively the peripheral blood lymphocyte subsets in pSS patients, and explored the relationship between lymphocyte subsets and disease activity. Next, peripheral blood CD4+ T cells were sorted using immunomagnetic beads. The proliferation, apoptosis, differentiation, and inflammatory factors of CD4+ T cells were determined using flow cytometry. Autophagosomes of CD4+ T cells were detected using transmission electron microscopy, autophagy-related proteins and genes were detected using western blotting or RT-qPCR.ResultsThe study demonstrated that the peripheral blood CD4+ T cells decreased in pSS patients, and negatively correlated with disease activity. UCMSC-Exos inhibited excessive proliferation and apoptosis of CD4+ T cells in pSS patients, blocked them in the G0/G1 phase, inhibited them from entering the S phase, reduced the Th17 cell ratio, elevated the Treg ratio, inhibited IFN-γ, TNF-α, IL-6, IL-17A, and IL-17F secretion, and promoted IL-10 and TGF-β secretion. UCMSC-Exos reduced the elevated autophagy levels in the peripheral blood CD4+ T cells of patients with pSS. Furthermore, UCMSC-Exos regulated CD4+ T cell proliferation and early apoptosis, inhibited Th17 cell differentiation, promoted Treg cell differentiation, and restored the Th17/Treg balance in pSS patients through the autophagy pathway.ConclusionsThe study indicated that UCMSC-Exos exerts an immunomodulatory effect on the CD4+ T cells, and maybe as a new treatment for pSS.

Emerging of a new CD3+CD31HCD184+ tang cell phenothype in Sjögren's syndrome induced by microencapsulated human umbilical cord matrix-derived multipotent stromal cells.

Sjögren's syndrome (SS) is an autoimmune disease hallmarked by infiltration and destruction of exocrine glands. Currently, there is no therapy that warrants full recovery of the affected tissues. Umbilical cord-derived multipotent stromal cells, microincapsulated in an endotoxin-free alginate gel (CpS-hUCMS), were shown to modulate the inflammatory activity of PBMCs in SS patients in vitro, through release of soluble factors (TGFβ1, IDO1, IL6, PGE2, VEGF). These observations led us to set up the present study, aimed at defining the in vitro effects of CpS-hUCMS on pro- and anti-inflammatory lymphocyte subsets involved in the pathogenesis of SS. Peripheral blood mononuclear cells (PBMCs) upon collection from SS patients and matched healthy donors, were placed in co-culture with CpS-hUCMS for five days. Cellular proliferation and T- (Tang, Treg) and B- (Breg, CD19+) lymphocyte subsets were studied by flow cytometry, while Multiplex, Real-Time PCR, and Western Blotting techniques were employed for the analysis of transcriptome and secretome. IFNγ pre-treated hUCMS were assessed with a viability assay and Western Blotting analysis before co-culture. After five days co-culture, CpS-hUCMS induced multiple effects on PBMCs, with special regard to decrease of lymphocyte proliferation, increase of regulatory B cells and induction of an angiogenic T cell population with high expression of the surface marker CD31, that had never been described before in the literature. We preliminarily showed that CpS-hUCMS can influence multiple pro- and anti-inflammatory pathways that are deranged in SS. In particular, Breg raised and a new Tang phenothype CD3+CD31HCD184+ emerged. These results may considerably expand our knowledge on multipotent stromal cell properties and may open new therapeutic avenues for the management of this disease, by designing ad hoc clinical studies.

The Critical Biomarkers Identification of Insulin Signaling Involved in Initiating cAMP Signaling Mediated Salivary Secretion in Sjogren Syndrome: Transcriptome Sequencing in NOD Mice Model

BackgroundSjogren’s syndrome (SS) is an autoimmune disorder characterized by the destruction of exocrine glands, resulting in dry mouth and eyes. Currently, there is no effective treatment for SS, and the mechanisms associated with inadequate salivary secretion are poorly understood.MethodsIn this study, we used NOD mice model to monitor changes in mice’s salivary secretion and water consumption. Tissue morphology of the submandibular glands was examined by H&E staining, and Immunohistochemical detected the expression of AQP5 (an essential protein in salivary secretion). Global gene expression profiling was performed on submandibular gland tissue of extracted NOD mice model using RNA-seq. Subsequently, a series of bioinformatics analyses of transcriptome sequencing was performed, including differentially expressed genes (DEGs) identification, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, PPI network construction, hub gene identification, and the validity of diagnostic indicators using the dataset GSE40611. Finally, IFN-γ was used to treat the cells, the submandibular gland tissue of NOD mice model was extracted, and RT-qPCR was applied to verify the expression of hub genes.ResultsWe found that NOD mice model had reduced salivary secretion and increased water consumption. H&E staining suggests acinar destruction and basement membrane changes in glandular tissue. Immunohistochemistry detects a decrease in AQP5 immunostaining within acinar. In transcriptome sequencing, 42 overlapping DEGs were identified, and hub genes (REN, A2M, SNCA, KLK3, TTR, and AZGP1) were identified as initiating targets for insulin signaling. In addition, insulin signaling and cAMP signaling are potential pathways for regulating salivary secretion and constructing a regulatory relationship between target-cAMP signaling-salivary secretion.ConclusionThe new potential targets and signal axes for regulating salivary secretion provide a strategy for SS therapy in a clinical setting.

Dysregulated long non-coding RNA in Sjögren’s disease impacts both interferon and adaptive immune responses

ObjectiveSjögren’s disease (SjD) is an autoimmune disease characterised by inflammatory destruction of exocrine glands. Patients with autoantibodies to Ro/SSA (SjDRo+) exhibit more severe disease. Long non-coding RNAs (lncRNAs) are a...

Research progress on the pathogenesis and quality of life of patients with primary Sjögren's syndrome complicated by depression.

In the past decade, an increasing number of studies have found a relationship between the occurrence and development of depression and autoimmune diseases, and the high prevalence of depression in patients with connective tissue diseases has also been confirmed. Primary Sjögren's syndrome (pSS) is a chronic autoimmune exocrinopathy characterised by lymphocytic infiltration and exocrine gland destruction. Depression in pSS patients is common, and the factors contributing to this condition are complicated. pSS patients with depression generally have a lower quality of life than pSS patients without depression. Several pathophysiological mechanisms involved in the condition have been proposed in recent years. Thus, in this review, we summarised recent progress on the impact of depression on pSS patients' quality of life, the possible pathogenesis underlying the development of depression in pSS patients and the management of such patients.

EP32 Gastroparesis in Sjögren’s syndrome

EP32 Gastroparesis in Sjögren’s syndrome

Systemic immunosuppressant for betterment of ocular manifestations of secondary Sjogren’s: A case report

Secondary sjogrens syndrome is an autoimmune disorder leading to destruction of exocrine glands with resultant classical clinical triad of dry eye, dry mouth and parotid gland enlargement in association with other systemic autoimmune diseasecommonly rheumatoid arthritis. This report highlights the unintended effect of systemic immunosuppresants given for the treatment of rheumatoid arthritis, in improving the coexistant corneal thinning and other ocular manifestation in a case ofsecondary sjogrens syndrome, which has been rarely reported. Modification of the immune response with systemic immunosuppressive agents improves severe keratoconjunctivitis sicca in recalcitrant secondary Sjogren syndrome.

Helicobacter Pylori Infection in Sjögren's Syndrome: Co-incidence or Causality?

Lymphoid cell infiltration and destruction of exocrine glands, specifically lacrimal and salivary glands are characteristics of Sjogren's syndrome (SS). An etiological role has been proposed for Helicobacter pylori (H. pylori), interacting in the clinical course and complications of SS (including gastric cancer and lymphoma). The aim of this study was to identify the probable correlation between H. pylori infection and Sjogren's syndrome (SS). In this case-control study, ELISA method was used to determine serum level of IgA and IgM anti H. pylori antibody in 43 subjects with SS according to the international criteria and 95 healthy subjects as control. SPSS-17 was used to analyze data with t-test. P value <0.05 were considered significant. Serum level of IgM (34.9% vs. 10.5%, p-value= 0.001) and IgA (67.4% vs. 46.3% p value= 0.021) anti H. pylori antibody were significantly higher in SS patients compared to the control group. There was a positive correlation between age and H. pylori infection (r=0.2, Pvalue= 0.05). Patients with SS had a higher prevalence of H. pylori infection compared to the normal population. Eradication of H. pylori is recommended particularly in older patients with SS.

Follicular helper and follicular cytotoxic T cells in primary Sjögren’s Syndrome: clues for an abnormal antiviral response as a pathogenic mechanism

Introduction: In chronic viral infections, T follicular helper (Tfh) cells are crucial to sustain CD8 cytotoxic T cells in face of the persistence of viral antigens. Moreover, the usual Th1 profile that is associated with antiviral responses in acute infections is replaced by a Tfh profile [1]. Primary Sjögren’s Syndrome (pSS) is a systemic autoimmune disease (SAD) with progressive destruction of exocrine glands. Viral infections have been proposed as etiological agents for pSS, but the connection between an abnormal Tfh-mediated antiviral response and pSS pathophysiology has not yet been established. Furthermore, as far as we know, the recently described T follicular cytotoxic cells (Tcf), also implicated in antiviral responses, have never been assessed in the context of pSS. Materials and methods: Five groups of patients were enrolled for this study: pSS patients classified according to the AECG criteria (n = 57), sicca syndrome patients with (n = 38) and without (n = 30) criteria for undifferentiated connective tissue disease (UCTD), patients with rheumatoid arthritis (RA; n = 20) and healthy controls (HC; n = 24). Peripheral blood samples from all patients and controls were analysed by 4-color flow cytometry, in a BD FACS Calibur. CD3, CD4, CXCR5, and CCR7 were used for the characterization of Tfh and Tcf cells. Tfh and Tfc were identified as the CXCR5 + CCR7- subset within CD4+ and CD4-(CD8+) T cells, respectively. The expression of IL-21 was also assessed in CD4 and CD8 T cells after cell stimulation with PMA + ionomycin. In the pSS group, EULAR Sjögren’s Syndrome Disease Activity Index (ESSDAI) scale was used to classify patients according to the disease activity. Patients were further divided in two groups: pSS with ESSDAI <5 (low activity) and pSS with ESSDAI ≥5 (moderate to high activity). Normality of cell subset data was assessed using D’Agostino & Pearson omnibus normality test. Unpaired Student’s t test with Welch’s correction was applied to compare normal variables while Mann-Whitney test was used for non-normal variables (p < 0.05 considered for both tests). Results: No differences were observed in pSS patients when compared to all other groups regarding either Tfh and Tcf cells. Nevertheless, IL-21 secreting CD4 T cells were increased in pSS patients compared to: HC (p = 0.0267); sicca patients without UCTD (p = 0.0158); sicca patients with UCTD (p = 0.0456) and RA patients (p = 0.0455). Similarly, IL-21 secreting CD8 T cells were also increased in pSS patients (p = 0.029) compared to HC. No differences were found in Tfh cells and Tcf cells, nor in IL-21 expression by T cells comparing either RA or sicca patients to HC. Interestingly, in pSS patients, Tcf cells were positively correlated with ESSDAI scores, particularly in those patients with longer disease duration (r = 0.430; p = 0.029). Considering disease activity, pSS patients with ESSDAI ≥5 (n = 8) presented a significantly increased percentage of Tcf cells (p = 0.0103). No other correlations between ESSDAI scores and IL-21-secreting T cells were observed. Discussion and conclusions: The increase in cells secreting IL-21, the signature cytokine for follicular T cells, seems to be a feature of pSS, not observed in RA nor in sicca syndrome. On the other hand, our data suggest Tcf cells are related to the disease activity in pSS, eventually highlighting their implication in the disease. Future studies approaching follicular T cell subsets, relevant in both autoimmune and antiviral responses could bring new insights for the comprehension of autoimmune diseases such as pSS.

Association of CD28 and CTLA4 haplotypes with susceptibility to primary Sjögren's syndrome in Mexican population.

Primary Sjögren's syndrome (pSS) is an autoimmune disease characterized by destruction of exocrine glands as a result of T and B cells infiltrated in glandular tissue. CD28 and CTLA-4 play a crucial role in T cell activation and inhibition. The aim of this study was to associate CD28 and CTLA4 haplotypes with susceptibility to pSS in patients from western Mexico. Polymerase chain reaction and restriction fragment length polymorphism were performed to identify CD28 and CTLA4 genotypes in 111 patients with pSS and 138 control subjects (CS). Haplotype analysis was carried out by SHEsis program. Soluble serum levels of CD28 (sCD28) and CTLA-4 (sCTLA-4) were quantified by ELISA kit. The CD28 GC haplotype was associated with low risk to pSS (2.5-folds, P<0.001). CTLA4 CAG and CGA were identified as genetic risk factor (P<0.001;OR=3.82[CI95%:2.022-7.296] and P<0.001; OR=11.38[CI95%:3.282-37.69] respectively). No difference in sCD28 and sCTLA-4 were found between patients and CS. However, pSS patients carriers of CD28 IVS3+17TC genotype showed high sCD28 (P=0.039 vs TT carriers in CS). In regard to sCTLA-4, patient who carry CTLA4-319C>T, +49 A>G, and +6230 G>A, or their haplotypes did not show any difference. Our findings suggest that CD28 GC, CTLA4 CAG, and CGA haplotypes are associated with susceptibility to pSS in patients from western Mexico. It seems that genetic control of CD28 and CTLA4 as well as local immune response in glandular tissue may regulate the impact of the gene expression in pSS. It is necessary to confirm this hypothesis in an integrative study.

Gastrointestinal and Hepatic Disease in Sjogren Syndrome.

Sjogren syndrome (SS) is a lymphocyte-mediated, infiltrative autoimmune disorder characterized by destruction of exocrine glands leading to secretory dysfunction. The typical manifestations include xerostomia and xerophthalmia; however, extensive gastrointestinal involvement is increasingly being recognized, emphasizing the variable and systemic nature of SS.

Pancreatic and Islet Remodeling in Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Knockout Ferrets

In cystic fibrosis (CF), there is early destruction of the exocrine pancreas, and this results in a unique form of diabetes that affects approximately half of adult CF individuals. An animal model of cystic fibrosis-related diabetes has been developed in the ferret, which progresses through phases of glycemic abnormalities because of islet remodeling during and after exocrine destruction. Herein, we quantified the pancreatic histopathological changes that occur during these phases. There was an increase in percentage ductal, fat, and islet area in CF ferrets over time compared with age-matched wild-type controls. We also quantified islet size, shape, islet cell composition, cell proliferation (Ki-67), and expression of remodeling markers (matrix metalloprotease-7, desmin, and α-smooth muscle actin). Pancreatic ducts were dilated with scattered proliferating cells and were surrounded by activated stellate cells, indicative of tissue remodeling. The timing of islet and duct proliferation, stellate cell activation, and matrix remodeling coincided with the previously published stages of glycemic crisis and inflammation. This mapping of remodeling events in the CF ferret pancreas provides insights into early changes that control glycemic intolerance and subsequent recovery during the evolution of CF pancreatic disease.

Renal manifestations of primary Sjogren's syndrome

Background and Objective: Sjogren's syndrome represents a group of diseases characterized by inflammation and destruction of exocrine glands. Renal involvement in Sjogren's syndrome has been reported in 18.4%–67% of patients. Distal renal tubular acidosis (RTA) was reported more common than proximal RTA which can present as acute hypokalemic paralysis. The aim of the present study was to investigate the clinical picture and the outcome in patients with primary Sjogren's syndrome (PSS) with significant renal involvement. Materials and Methods: We conducted a retrospective study of PSS patients with significant renal involvement in our department. Results: A total of 27 patients were included in the study. The mean age was 39.3 ± 4.5 with a mean follow-up of 42 ± 4.8 months. About 18 patients had hypokalemia associated with paralysis, and 4 patients had hypokalemia without paralysis. Female: male ratio was 12.5:1. Number episodes of hypokalemic paralysis range from 1 to 4. The mean time of recovery was 20.4 ± 4 h, and mean potassium requirement was 190 ± 45 mEq intravenously. The mean serum potassium was 2.51 ± 0.55, mean urinary potassium 32 ± 2.3 mEq/day, mean serum bicarbonate 15.03 ± 1.05 mEq/l, and mean blood pH 7.28 ± 0.9. About twenty had distal RTA, and two had proximal RTA. The clinical symptoms were myalgia in 24 (88%), ocular symptoms in 20 (74%), muscular paralysis (66%), oral in 18 (66%), and dental caries in 12 (44%). Five patients underwent renal biopsy of which two showed acute interstitial nephritis, one showed chronic interstitial nephritis, one showed membranoproliferative glomerulonephritis, and one acute tubular injury. Conclusion: The clinical implication of our study is that distal RTA is a common feature of Sjogren's syndrome presenting predominantly as hypokalemic paralysis.

Exploring BAFF: its expression, receptors and contribution to the immunopathogenesis of Sjögren's syndrome.

SS is an autoimmune condition characterized by exocrine gland destruction, autoantibody production, immune complex deposition and systemic complications associated with lymphocytic infiltration of many organs. Genetic, environmental and viral factors play a role in disease aetiology, however, the exact mechanisms driving the immunopathogenesis of SS remain uncertain. Here we discuss a role for B cell activating factor (BAFF), whereby B cell hyperactivity and increased BAFF secretion observed in patients and animal models of the disease can be explained by the altered expression of cell-specific BAFF/BAFF receptor (BAFF-R) variants in several immune cell types. Understanding the role of BAFF/BAFF-R heterogeneity in SS pathogenesis could help to facilitate new treatment strategies for patients.

Profiling Micro-RNA expression in patients with Primary Sjogrens Syndrome – contribution to disease pathogenesis

Background Sjogrens syndrome (SS) is a chronic autoimmune disorder, characterised by lymphocytic infiltration resulting in exocrine gland destruction and other extra-glandular manifestations [1]. Currently there is no definitive diagnostic test, and the immuno-pathology is not fully understood. Recently focus has shifted to investigating microRNAs (miRs) in an effort to understand the mechanisms contributing to disease pathogenesis. MiRs are short non-coding RNA sequences, which regulate gene expression posttranscriptionally [2]. Of note, miRs have been identified as key regulators of immune function in a variety of autoimmune conditions [2]. The hypothesis of this project is that alterations in expression of specific miRs which regulate genes relating to inflammation and immunity may play a role in the pathology of the disease.

A rapamycin-binding protein polymer nanoparticle shows potent therapeutic activity in suppressing autoimmune dacryoadenitis in a mouse model of Sjögren's syndrome

Sjögren's syndrome (SjS) is a chronic autoimmune disease characterized initially by lymphocytic infiltration and destruction of exocrine glands, followed by systemic organ damage and B-cell lymphoma. Conventional treatment is based on management of symptoms and there is a shortage of therapies that address the underlying causes of inflammation at source exocrine tissue. The aim of this study was to test a novel protein polymer-based platform consisting of diblock copolymers composed from Elastin-like Polypeptides (ELPs) fused with FKBP12, to deliver a potent immunosuppressant with dose-limiting toxicity, rapamycin (Rapa) also known as Sirolimus, and evaluate its effects on the inflamed lacrimal gland (LG) of non-obese diabetic mouse (NOD), a classic mouse model of SjS. Both soluble and diblock copolymer ELPs were fused to FKBP12 and characterized with respect to purity, hydrodynamic radii, drug entrapment and release. Both formulations showed successful association with Rapa; however, the nanoparticle formulation, FSI, released drug with nearly a 5 fold longer terminal half-life of 62.5h. The strong interaction of FSI nanoparticles with Rapa was confirmed in vivo by a shift in the monoexponential pharmacokinetic profile for free drug to a biexponential profile for the nanoparticle formulation. When acutely administered by injection into NOD mice via the tail vein, this FSI formulation significantly suppressed lymphocytic infiltration in the LG relative to the control group while reducing toxicity. There was also a significant effect on inflammatory and mammalian target of Rapamycin (mTOR) pathway genes in the LG and surprisingly, our nanoparticle formulation was significantly better at decreasing a proposed tear biomarker of SjS, cathepsin S (CATS) compared to free drug. These findings suggest that FSI is a promising tool for delivering Rapa for treatment of SjS in a murine model and may be further explored to meet the unmet medical challenge of SjS.