Circulating cell-free DNA correlate to disease activity and treatment response of patients with radiographic axial spondyloarthritis.

Microdamage and its related inflammation contribute to the development of radiographic axial spondyloarthritis (r-axSpA). Inflammation and cell death in damaged tissues are associated with cell-free DNA (cfDNA) release. Here we investigated whether circulating cfDNA could be a potential biomarker for evaluating disease activity and treatment response in r-axSpA. Circulating cfDNA was detected in the discovery and validation cohort with 79 and 60 newly diagnosed r-axSpA patients respectively and 42 healthy controls using the Quant-iT PicoGreen dsDNA reagent and kit. As a result, cfDNA levels were significantly higher in r-axSpA patients compared with healthy controls in the discovery and validation cohort. Moreover, cfDNA levels were positively correlated with CRP, ASDAS-CRP and neutrophil counts. Additionally, non-steroid anti-inflammatory drugs (NSAIDs) combined with disease-modifying anti-rheumatic drugs or tumor necrosis factor inhibitors but not NSAIDs alone could reduce cfDNA levels. Moreover, a decrease of cfDNA levels after treatment was associated with an effective therapeutic response. Intriguingly, patients with higher levels of cfDNA at diagnosis responded better to combination therapy rather than NSAIDs. However, patients with lower levels of cfDNA displayed similar responses to combination or mono-NSAID treatment. In conclusion, circulating cfDNA levels showed a significant correlation with disease activity as well as treatment efficacy in patients with r-axSpA. Moreover, cfDNA at diagnosis might predict the response to different therapy. Consequently, cfDNA may serve as a useful biomarker of inflammation in r-axSpA.

Expression of CFTR, a hallmark gene of ionocytes, is downregulated in salivary glands of Sjögren's syndrome patients.

INTRODUCTION: The autoimmune exocrinopathy, Sjögren's syndrome (SjS), is associated with secretory defects in salivary glands. The cystic fibrosis transmembrane conductance regulator (CFTR) of the chloride channel is a master regulator of fluid secretion, but its role in SjS has not been investigated. Our research found a link between CFTR and SjS at the genetic and protein levels, as well as through clinical data. METHODS: We used single-cell RNA sequencing to identify the presence of CFTR in glandular epithelial cells of the human salivary gland (scRNA-seq) and confirmed the difference using immunofluorescence tests in labial glands and clinical data statistics from 44 non-SjS and 36 SjS patients. RESULTS: The changes of CFTR expression in salivary glands of SjS patients was assessed at both mRNA and protein levels. According to the scRNA-seq analyses, CFTR was the hallmark gene of ionocytes. We firstly identified that SjS had a lower level of CFTR expression in the labial glands than non-SjS at mRNA level. Using immunofluorescence assays, we also found that CFTR expression was decreased in SjS patients compared to non-SjS. The results of the clinical statistics revealed that CFTR expression was adversely correlated with feelings of dry mouth, lymphocyte infiltration in the labial glands, and certain autoantibodies in serum (antinuclear antibody, anti-Ro/SSA, and anti-La/SSB antibodies). CONCLUSION: Those findings above proved an obviously downregulated expression of CFTR in salivary glands of SjS patients and its clinical significance. Dysfunction in CFTR or ionocytes may contribute to SjS pathogenesis and represents a promising therapeutic target.

Immunological Changes in Peripheral Blood of Ankylosing Spondylitis Patients during Anti-TNF-α Therapy and Their Correlations with Treatment Outcomes.

Tumor necrosis factor-α (TNF-α) inhibitors are the main types of biological conventional synthetic disease-modifying antirheumatic drugs and have efficacy in treating ankylosing spondylitis (AS) which is not sensitive for nonsteroidal anti-inflammatory drug. However, the impact of TNF-α inhibitors on immune cells in patients with AS is still clearly undefined, and the impact of immune cells on treatment response is also largely elusive. This study is aimed at evaluating the longitudinal changes of circulating immune cells after anti-TNF-α therapy and their associations with treatment response in AS patients. Thirty-five AS patients receiving the treatment of anti-TNF-α therapy were included into this prospective observational study. The frequencies of immune cells including Th1, Th2, Th17, regulatory T cell (Treg), T follicular helper cell (Tfh), and regulatory B cell (Breg) in the peripheral blood were measured by flow cytometry at baseline and 4 time points after therapy. The difference in the circulating immune cells between responders and nonresponders was compared. This study suggested that anti-TNF-α therapy could significantly reduce circulating proinflammatory immune cells such as Th17 and Tfh, but significantly increased the percentages of circulating Treg and Breg. Moreover, circulating Breg may be a promising predictor of response to anti-TNF-α therapy in AS patients.

Associations of Platelet Count with Inflammation and Response to Anti-TNF-α Therapy in Patients with Ankylosing Spondylitis.

Background: Increased platelet count has been reported in ankylosing spondylitis (AS) patients, but its clinical significance is still largely elusive. The objective of this study was to evaluate the clinical role of platelet count in AS patients, especially its impact on treatment outcomes. Methods: A case-control study containing 35 AS patients receiving anti-tumor necrosis factor-α (anti-TNF-α) therapy and 45 healthy controls was performed, and AS patients were followed at least 6 months after anti-TNF-α therapy. A systematic review and meta-analysis of studies containing relevant data on outcomes of interest was also performed. Results: AS patients had significantly higher platelet count than controls (p = 0.0001), and the significantly increased platelet count in AS patients was confirmed in a meta-analysis of 14 studies involving 1,223 AS patients and 913 controls (mean difference = 39.61, 95% CI 27.89-51.34, p < 0.001). Besides, platelet count was significantly correlated with ESR (p < 0.001) and was moderately correlated with ASDAS-CRP score (p = 0.002). Moreover, anti-TNF-α therapy could reduce platelet count in AS patients at the first month and the effect was maintained through the treatment duration. In the prospective follow-up study of those 35 AS patients, those responders to anti-TNF-α therapy had significantly lower platelet count than nonresponders (p = 0.015). Logistic regression analysis suggested that lower platelet count was associated with higher possibility of achieving good response to anti-TNF-α therapy in AS patients (odds ratio = 2.26; 95% CI = 1.06-4.82; p = 0.035). Conclusion: This study suggested that platelet count was associated with inflammation severity and treatment outcomes in AS patients, and elevated platelet count was a promising biomarker of poorer response to anti-TNF-α therapy. The findings above need to be validated in more future studies.

Serological Evidence for the Association Between Epstein-Barr Virus Infection and Sjögren's Syndrome.

Background: Exposure to Epstein-Barr virus (EBV) infection has been hypothesized to be an important risk factor for multiple rheumatic diseases, but the serological evidence so far for its role in Sjögren's syndrome (SjS) is not clearly established yet. This study aimed to assess the seroepidemiological associations of antibodies to EBV with SjS. Methods: A seroepidemiological study containing 119 patients with SjS and 65 healthy controls was first performed, in which the associations of SjS with four commonly studied EBV antibodies including IgM-anti-viral capsid antigen (anti-VCA) antibody, IgG-anti-VCA antibody, IgG-anti-early antigen (anti-EA) antibody, and IgG-anti-EBV nuclear antigen 1 (anti-EBNA1) antibody were evaluated. A systematic review and meta-analysis of eligible seroepidemiological studies was also carried out, and data syntheses were performed using random-effect meta-analysis. Results: In the case-control study, the patients with SjS had both a significantly higher prevalence of IgG-anti-EA antibody positivity (31.9% vs. 3.1%, P < 0.001) and high titers of IgG-anti-EA antibody (P < 0.001) than healthy controls. The titer of IgG-anti-VCA antibody was significantly increased in the patients with SjS compared with healthy controls (P < 0.001). IgG-anti-EA antibody seropositive patients with SjS had lower levels of both C3 (P = 0.002) and C4 (P = 0.02), and the titer of IgG-anti-EA antibody was inversely related to the levels of both C3 (r = -0.31, P < 0.001) and C4 (r = -0.20, P = 0.03). A total of 14 eligible studies on the serological associations between EBV infection and SjS were finally included into the meta-analysis, which suggested obvious associations of SjS with IgM-anti-VCA antibody [Odds ratio (OR) = 5.77, 95%CI 1.73-19.25, P = 0.004] and IgG-anti-EA antibody (OR = 9.97, 95%CI 4.58-21.67, P < 0.00001). Conclusions: The findings from this study provide strong serological evidence for the association between EBV infection and SjS. SjS has obvious associations with IgM-anti-VCA antibody and IgG-anti-EA antibody. IgG-anti-EA antibody is linked to low levels of C3 and C4 in the patients with SjS, the significance of which needs to be addressed in further studies.

Osteoprotegerin interacts with syndecan-1 to promote human endometrial stromal decidualization by decreasing Akt phosphorylation.

STUDY QUESTION: Does osteoprotegerin (OPG) promote human endometrial stromal decidualization? SUMMARY ANSWER: OPG is essential for human endometrial stromal decidualization through its interaction with syndecan-1 to decrease Akt phosphorylation. WHAT IS KNOWN ALREADY: OPG (a cytokine receptor) levels are significantly increased in the circulation of pregnant women. However, the role and mechanism of OPG in human endometrial stromal cell (ESC) decidualization remain elusive. STUDY DESIGN, SIZE, DURATION: We analyzed the endometrial expression of OPG in endometrial tissue samples collected from women with regular menstrual cycles (ranging from 25 to 35 days), and decidual tissue samples collected from woman with normal early pregnancy or recurrent pregnancy loss (RPL) who visited the Department of Gynecology and Obstetrics at a tertiary care center from January to October 2018. None of the subjects had hormonal treatment for at least 3 months prior to the procedure. In total, 16 women with normal early pregnancy and 15 with RPL were selected as subjects for this study. The function of OPG in decidualization was explored in a human endometrial stromal cell (HESC) line and primary cultures of HESCs. PARTICIPANTS/MATERIALS, SETTING, METHODS: We collected endometrial tissues (by biopsy) from the subjects during their menstrual cycle and decidual tissues from subjects with a normal early pregnancy and those with RPL at the time of dilation and curettage. The control group comprised randomly selected women who underwent termination of an apparently normal early pregnancy. The endometrial OPG expression was analyzed using immunohistochemical staining and quantitative RT-PCR (qRT-PCR). Immunofluorescence staining and western blot, and qRT-PCR were used to explore the mRNA and protein expression, respectively, of OPG in an immortalized HESC line and in primary cultures of HESC during proliferation and decidualization. siRNA-mediated knockdown experiments were performed to examine the function of OPG in HESC proliferation and decidualization. Flow cytometry and the cell proliferation MTS assay were performed to further examine the role of OPG in HESC proliferation. We also analyzed decidual marker gene expression by qRT-PCR to assess the consequences of OPG loss for HESC decidualization. A co-immunoprecipitation (IP) assay was used to determine the potential interaction between the OPG and Syndecan-1. Western blot analysis of the rescue experiments performed using the phosphatidylinositol 3-kinase (PI3K) signaling-specific inhibitor LY294002 was used to investigate the downstream signaling pathways through which OPG could mediate HESC decidualization. MAIN RESULTS AND THE ROLE OF CHANCE: OPG was expressed in both the human endometrium and in vitro decidualized ESCs. Knockdown experiments revealed that OPG loss impaired the expression of IGF-binding protein-1 (IGFBP-1) (P < 0.05) and prolactin (PRL) (P < 0.05), two specific markers of decidualization, in HESC undergoing decidualization. We also uncovered that OPG knockdown induced the aberrant activation of Akt (protein kinase B) during HESC decidualization (P < 0.05). The inhibition of Akt activation could rescue the impaired expression of the decidual markers PRL (P < 0.05) and IGFBP-1 (P < 0.05) in response to OPG knockdown. Syndecan-1 was considered a potential receptor candidate, as it was expressed in both the endometrium and in vitro cultured stromal cells. Subsequent co-IP experiments demonstrated the interaction between OPG and Syndecan-1 during decidualization. In addition, Syndecan-1 knockdown not only clearly attenuated the decidualization markers PRL (P < 0.05) and IGFBP-1 (P < 0.05) but also induced the aberrant enhancement of Akt phosphorylation in decidualized cells, consistent with the phenotype of OPG knockdown cells. Finally, we revealed that the transcript and protein expression of both OPG and Syndecan-1 was significantly lower in the decidual samples of women with RPL than in those of women with normal pregnancy (P < 0.05). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: In this study, based on a number of approaches, it was demonstrated that OPG mediated the repression of Akt that occurs during human stromal cell decidualization, however, the molecular link between OPG and Akt signaling was not determined, and still requires further exploration. WIDER IMPLICATIONS OF THE FINDINGS: OPG is required for decidualization, and a decrease in OPG levels is associated with RPL. These findings provide a new candidate molecule for the diagnosis and potential treatment of RPL. STUDY FUNDING/COMPETING INTEREST(S): This work was supported in part by the National Natural Science Foundation of China U1605223 (to G.S.), 81701457 (to Y.J.) and 81601349 (to Y.J.). The authors have no conflicts of interest to disclose.

Lymphocyte infiltration and key differentially expressed genes in the ulcerative colitis.

BACKGROUND: Ulcerative colitis (UC) was a type of inflammatory bowel diseases, which was difficult to cure and even would malignant turn into colon cancer. The specific etiology and molecular mechanism of UC were unclear to date. The purpose of this study was to search for new targets for the diagnosis and treatment of UC. METHODS: Firstly, we downloaded the gene expression data of UC from the gene expression omnibus database database (GSE107499), and used multiple bioinformatics methods to find differently expressed genes (DEGs) in UC. Subsequently, we evaluated the lymphocyte infiltration in UC inflamed colon tissue by using the cell type identification by estimating relative subset of known RNA transcripts method. RESULTS: We obtained 1175 DEGs and 8 hub genes (IL6, TNF, PTPRC, CXCL8, FN1, CD44, IL1B, and MMP9) in this study. Among them, 903 DEGs were up-regulated and 272 DEGs were down-regulated. Compared with non-inflamed colon tissues, the inflamed colon tissues had higher levels of memory B cells, activated memory CD4 T cells, follicular helper T cells, M1 macrophages, resting dendritic cells, activated dendritic cells, activated mast cells, and neutrophils, whereas the proportions of plasma cells, resting memory CD4 T cells, gamma delta T cells, activated NK cells, M2 macrophages and resting mast cells were relatively lower. CONCLUSIONS: The DEGs, hub genes and different lymphatic infiltration conditions can provide new targets for diagnosis and treatment of UC. However, these were just predictions through some theoretical methods, and more basic experiments will be needed to prove in the future.

Anti-recoverin antibodies indicate fundus abnormalities in systemic lupus erythematosus.

OBJECTIVES: Lupus fundus abnormalities are a sight-threatening complication of systemic lupus erythematosus (SLE) and its pathogenesis remains to be studied. The aim of this study was to assess the clinical characteristics associated with the presence of anti-recoverin antibodies in patients with SLE, especially those with fundus abnormalities. METHODS: Seventy-six participants were enrolled, including 21 patients with fundus abnormalities (fundus group), 30 patients without fundus abnormalities (non-fundus group) and 25 healthy individuals. Serum anti-recoverin antibody levels were measured using enzyme-linked immunosorbent assay, and clinical and laboratory data were obtained from medical records. RESULTS: Compared with the non-fundus group, the fundus group had a higher incidence of hematuria (p < 0.05). The Systemic Erythematosus Disease Activity Index (SLEDAI) score in the fundus group was significantly higher than the non-fundus group (21.48 ± 8.06 versus 10.80 ± 5.74, p < 0.001). The levels of serum anti-recoverin antibodies in the fundus group were significantly higher than the non-fundus group (p = 0.029) or the healthy control group (p = 0.011). Anti-recoverin-negative and -positive patients differed on a number of clinical parameters, including incidence of fever, rash, antinuclear antibody, anti-dsDNA antibody, erythrocyte sedimentation rate, immunoglobulin G, complement C3 and complement C4. The average SLEDAI score of anti-recoverin-positive patients was significantly higher than anti-recoverin-negative patients (17.73 ± 8.11 versus 12.56 ± 8.37, p < 0.05). CONCLUSIONS: Anti-recoverin antibodies were related to higher disease activities in SLE, especially those with fundus abnormalities, suggesting that anti-recoverin antibodies may play an important role in the pathogenesis of fundus abnormalities in SLE.

Peptide-Based Vaccination Therapy for Rheumatic Diseases.

Rheumatic diseases are extremely heterogeneous diseases with substantial risks of morbidity and mortality, and there is a pressing need in developing more safe and cost-effective treatment strategies. Peptide-based vaccination is a highly desirable strategy in treating noninfection diseases, such as cancer and autoimmune diseases, and has gained increasing attentions. This review is aimed at providing a brief overview of the recent advances in peptide-based vaccination therapy for rheumatic diseases. Tremendous efforts have been made to develop effective peptide-based vaccinations against rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), while studies in other rheumatic diseases are still limited. Peptide-based active vaccination against pathogenic cytokines such as TNF-α and interferon-α (IFN-α) is shown to be promising in treating RA or SLE. Moreover, peptide-based tolerogenic vaccinations also have encouraging results in treating RA or SLE. However, most studies available now have been mainly based on animal models, while evidence from clinical studies is still lacking. The translation of these advances from experimental studies into clinical therapy remains impeded by some obstacles such as species difference in immunity, disease heterogeneity, and lack of safe delivery carriers or adjuvants. Nevertheless, advances in high-throughput technology, bioinformatics, and nanotechnology may help overcome these impediments and facilitate the successful development of peptide-based vaccination therapy for rheumatic diseases.

Identification of the tubulointerstitial infiltrating immune cell landscape and immune marker related molecular patterns in lupus nephritis using bioinformatics analysis.

BACKGROUND: Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that commonly affects the kidneys. Research into markers that can predict the prognosis of tubulointerstitial lupus nephritis (LN) has been impeded by the lack of well-designed studies. METHODS: In this study, we selected and merged 3 sets of renal biopsy tubulointerstitial data from GSE32591, GSE69438, and GSE127797, including 95 LN and 15 living healthy donors. CIBERSORTx was utilized for differentially infiltrating immune cell (DIIC) analysis. Weighted Gene Co-Expression network analysis (WGCNA) was employed to explore differentially expressed gene (DEG) related modules. Combined WGCNA hub genes and protein-protein interaction (PPI) validation was used for immune marker identification. Lastly, unsupervised clustering was carried out to validate the correlation between these markers and clinical characteristics. RESULTS: Our findings unveiled TYROBP, C1QB, LAPTM5, CTSS, PTPRC as the 5 immune markers, which were negatively correlated with glomerular filtration rate (GFR). Specifically, the expression levels of TYROBP and C1QB were significantly different between proliferative LN (PLN) and membranous LN (MLN). Unsupervised clustering could aggregate LN by these immune marker expression spectrums. CONCLUSIONS: This study is the first to identify infiltrating immune cells and associated molecular patterns in the tubulointerstitium of LN by utilizing bioinformatics methods. These findings contribute to a better understanding of the mechanisms behind LN, and promote more precise diagnosis.

Efficiency of Therapeutic Plasma-Exchange in Acute Interstitial Lung Disease, Associated With Polymyositis/Dermatomyositis Resistant to Glucocorticoids and Immunosuppressive Drugs: A Retrospective Study.

Interstitial lung disease (ILD) is a life-threating complication, commonly associated with polymyositis (PM), and dermatomyositis (DM). A subset of acute ILD associated with PM/DM patients are refractory to conventional treatment, and leads to a high rate of mortality. The efficacy of therapeutic plasma-exchange (TPE) as a PM/DM treatment to improve muscle involvement is controversial due to a lack of evidence. However, in recent reports, TPE has been effective in improving lung involvement. To evaluate the efficacy of this therapy, we retrospectively studied TPE treatment outcomes for in 18 acute PM/DM-ILD patients who were resistant to conventional therapies. Five patients were diagnosed with DM (27.8%), 11 with CADM (61.1%), and two with PM (11.1%). Among 18 patients, 11 (61.1%) achieved satisfactory improvement after four or more rounds of TPE, whereas seven died due to respiratory failure. We also analyzed risk factors to predict unresponsiveness to TPE in these patients. Notably, the prevalence of subcutaneous/mediastinal emphysema was significantly higher in the non-responsive group (6/7, 85.7%) than in the responsive group (2/11, 18.2%; P = 0.013); moreover, patients with this complication were mainly in the CADM subgroup (6/8, 75%). Subcutaneous/mediastinal emphysema and increased serum ferritin levels were shown to be poor prognostic factors, predictive of unresponsiveness to TPE, in PM/DM patients. No autoantibodies were found to be associated with TPE outcome, although we only investigated anti-Jo-1 and anti-Ro antibodies; the clinical significance of other myositis-specific autoantibodies, especially anti-melanoma differentiation-associated gene 5 (MDA5) antibody, is not known. Our results indicate that TPE might be an alternative treatment for acute PM/DM-ILD patients resistant to conventional therapies, except for those with subcutaneous/mediastinal emphysema and high serum ferritin levels.

Role of Galphaq in pathogenesis of psoriasis, a new mechanism about the immune regulation in psoriasis.

Psoriasis (PSO) is a chronic inflammatory skin disease characterized with skin lesions and abnormal keratinocyte proliferation. The immune dysregulation is involved in the pathogenesis of PSO. However, the detail of immune regulation in PSO is still not very clear. Gαq, the alpha subunit of the Gq protein, played important role in the immune regulation. In this study, we aimed to investigate whether Gαq was involved in the pathogenesis of PSO. We detected the Gαq expression level and analyzed its relationship with test parameters of PSO patients. Furthermore, we used imiquimod to induce PSO mouse model in Gnaq -/- bone marrow (BM) chimeric mice. The inflammatory cytokines and its correlation with Gαq expression were analyzed both in PSO patients and mice. The results showed that the Gαq expression in PSO patients was much lower and negatively correlated with PSO Area and Severity Index (PASI), CRP, cholesterol and low-density lipoprotein. In PSO mice models, the skin lesion and keratinocyte proliferation were much more serious in Gnaq -/- BM chimeric mice. Also, the proportions of Th17 cells in Gnaq -/- BM chimeric mice were much higher than WT mice. Furthermore, the IL-17A and TNF-α in Gnaq -/- chimeric mice were also higher. Moreover, IL-17A and TNF-α in PSO patients were negatively associated with the Gαq expression. Our results indicated that Gαq was involved in the pathogenesis of PSO, and its regulation on Th17 cell differentiation and cytokine production might contribute to part of the mechanism of immune dysfunction of PSO.

Loss of Perp in T Cells Promotes Resistance to Apoptosis of T Helper 17 Cells and Exacerbates the Development of Experimental Autoimmune Encephalomyelitis in Mice.

T helper 17 (Th17) cells are crucial for the pathogenesis of multiple sclerosis (MS) in humans and experimental autoimmune encephalomyelitis (EAE) in animals. High frequency of Th17 cells and low sensitivity to activation-induced cell death (AICD) are detected in MS patients. However, the mechanisms underlying apoptosis resistance of T cells remain unclear. Perp is an apoptosis-associated target of p53 and implicated in the development of cancers. Here, we show that loss of Perp in T cells does not affect Th1, Th17, or Treg cell differentiation, but does significantly increase the resistance of Perp-/- Th17 cells to AICD and anti-Fas in Lck-Cre × Perpfl/fl mice by inhibiting the caspase-dependent apoptotic pathway. Moreover, Lck-Cre × Perpfl/fl mice exhibited earlier onset of EAE and severe spinal cord inflammation and demyelination, accompanied by increased levels of pro-inflammatory cytokines and enlarged population of Th17 cells. Therefore, Perp deletion promoted Th17 responses and exacerbated the development and severity of EAE.

Investigation of autoantibodies to SP-1 in Chinese patients with primary Sjögren's syndrome.

In order to evaluate autoantibody to SP-1 as an early biomarker in pSS, we investigated autoantibody to SP-1 in Chinese patients with primary Sjögren's syndrome (pSS). Autoantibodies to SP-1 are significantly increased in pSS patients compared to RA patients, SLE patients, and healthy people without secondary SS. The presence of anti SP-1 antibodies was negatively correlated with the focus score (FS), RF, and salivary gland function. It was positively correlated with FS=0, RF≤20, and normal salivary gland function. In further studies, the autoantigen SP-1 was identified in ductal epithelia of salivary glands in il14α TG mice by IIF. SP-1 mRNAs expression increased with growing age in il14α TG mice. SP-1 mRNA was also identified in labial biopsies of patients with pSS. In conclusion, autoantibody to SP-1 is an early marker in pSS. It is useful to diagnose pSS patients who lack RF or antibodies to Ro/La.

MicroRNA-488 and -920 regulate the production of proinflammatory cytokines in acute gouty arthritis.

BACKGROUND: Gout is considered one of the most painful acute conditions caused by deposition of monosodium urate (MSU) crystals within joints. Recent studies have shown that interleukin (IL)-1ß is a key inflammatory mediator in acute gouty arthritis (GA), and its level is regulated by microRNAs (miRNAs). However, the molecular mechanisms of the regulation remain unclear. METHODS: A miRNA microarray was used to analyze the miRNA expression profiles in peripheral white blood cells (WBCs) of patients with GA. THP-1 cells were transfected with miRNA mimics, stimulated by MSU crystals, and then subjected to quantitative real-time polymerase chain reaction or Western blot analysis. Levels of IL-1ß, IL-8, and tumor necrosis factor (TNF)-α in culture supernatants of THP-1 cells were measured by enzyme-linked immunosorbent assay. A luciferase reporter assay was conducted to confirm the interaction of miRNA and IL-1ß 3'-untranslated regions (UTRs). RESULTS: Combining bioinformatics and miRNA expression profiles, we found five miRNAs (hsa-miR-30c-1-3p, hsa-miR-488-3p, hsa-miR-550a-3p, hsa-miR-663a, and hsa-miR-920) that possibly target IL-1ß. Then, we demonstrated that miR-488 and miR-920 were significantly decreased in the WBCs of patients with GA and that MSU crystals could inhibit expression of miR-488 and miR-920. Upregulation of miR-488 and miR-920 could suppress MSU-induced IL-1ß protein expression in THP-1 cells, but no significant difference in IL-1ß messenger RNA levels was observed. Moreover, we found that miR-488 and miR-920 could directly target the 3'-UTR of IL-1ß. Overexpression of miR-488 and miR-920 could significantly inhibit the gene and protein expression of IL-8 and TNF-α in MSU-induced THP-1 cells. CONCLUSIONS: This study demonstrates the roles of miR-488 and miR-920 in regulating the production of proinflammatory cytokines in the pathogenesis of GA. These findings suggest that miR-488 and miR-920 could serve as potential therapeutic targets in the treatment of GA.

IL-33-induced alternatively activated macrophage attenuates the development of TNBS-induced colitis.

Accumulated data have shown that alternatively activated macrophage exerts a modulatory role in many diseases, including colitis. Interleukin-33 (IL-33), a critical modulator in adaptive and innate immune, has been implicated in autoimmunity and inflammation. Previously, we have reported that IL-33 functions as a protective modulator in TNBS-induced colitis, which is closely related to a Th1-to-Th2/Treg switch. Here, we present novel evidence suggesting that IL-33 primes macrophage into alternatively activated macrophages (AAM) in TNBS-induced colitis. The strong polarized effect of IL-33 was tightly associated with the markedly increased induction of Th2-type cytokines. To confirm the beneficial effects of AAM induced by IL-33, peritoneal AAMs isolated from IL-33-treated mice were transferred to recipient mice with TNBS colitis. The adoptive transfer resulted in prominent inhibition of disease activity and inflammatory cytokines in the TNBS-treated mice. In conclusion, our data provide clear evidence that IL-33 plays a protective role in TNBS-induced colitis, which is closely related to AAM polarization.

A Potential of sFasL in Preventing Gland Injury in Sjogren's Syndrome.

Fas and its ligand FasL, members of tumor necrosis factor receptor superfamily, have been implicated in the process of cell apoptosis. FasL consists of two forms, membrane FasL (mFasL) and soluble FasL (sFasL). sFasL can be produced by mFasL cleaved by matrix metalloproteinases (MMP) and also reveals a role for binding to Fas which is expressed on cell surface. Although Fas/FasL axis has been implicated in a variety of diseases, its role in Sjogren's syndrome still remains ill defined. In this study, we investigated the potential of sFasL in the pathogenesis of Sjogren's syndrome (SS). We found that the serum levels of sFasL in SS patients were significantly lower than healthy subjects. Moreover, serum levels of sFasL in patients with mild disease activity were higher than patients with severe disease activity. There is a positive correlation of the serum level of sFasL with uptake index of parotid gland in our expectation. In addition, liver injury involvement in SS patients showed decreased level of sFasL. Furthermore, we here also observed that the protective cytokine IL-10 expression was positively correlated with sFasL expression. Thus, our results here suggest a potential of sFasL in maintaining gland organ homeostasis.

Autoantibody to MDM2: A potential serological marker of primary Sjogren's syndrome.

INTRODUCTION: Primary Sjogren's Syndrome (pSS) is one of the autoimmune diseases characterized by polyclonal autoantibody production. The human homologue of the mouse double minute 2 (MDM2) is an important negative regulator of p53. Our previous study indicated that autoantibody to MDM2 can be detected in systemic lupus erythematosus patients. The purpose of this study is to study anti-MDM2 autoantibody in pSS patients. METHODS: Anti-MDM2 autoantibody in sera from 100 pSS patients and 74 normal controls was investigated by ELISA. Positive samples were further confirmed by western blotting. Expression of MDM2 in labial gland tissue from pSS patients and normal controls was checked by immunohistochemistry. The difference in clinical characteristics and laboratory findings between anti-MDM2 positive and anti-MDM2 negative pSS patients was analyzed. RESULTS: The presence of anti-MDM2 autoantibody in pSS patients was 21.0%, significantly higher than normal controls (5.40%). MDM2 was overexpressed in labial gland from pSS patients. pSS patients with positive anti-MDM2 were characterized by longer disease duration and more lymphocytes focal gathering in labial gland. Prevalence of anemia, thrombocytopenia and anti-SSB was significantly higher in pSS patients with anti-MDM2 autoantibody. Titer of anit-MDM2 was negatively associated with hemoglobin level, platelet count, complement 3 level and complement 4 level, positively associated with European Sjogren's syndrome disease activity index (ESSDAI) and level of IgG. CONCLUSIONS: Anti-MDM2 autoantibody may be used as a potential serological biomarker in pSS disease activity evaluation. Study on the role of anti-MDM2 or MDM2 in pSS may help us know the pathogenesis mechanism of pSS better.

Decreased Gαq expression in T cells correlates with enhanced cytokine production and disease activity in systemic lupus erythematosus.

Aberrant T cell immune responses appear central to the development of systemic lupus erythematosus (SLE). We previously reported that Gαq, the alpha subunit of Gq, regulates T and B cell immune responses, promoting autoimmunity. To address whether Gαq contributes to the pathogenesis of SLE, Gαq mRNA expression was studied using real time-PCR in PBMCs and T cells from SLE patients as well as age- and sex-matched healthy controls. Our results showed that Gαq mRNA expression was decreased in PBMCs and T cells from SLE patients compared to healthy individuals. Correlation analyses showed that Gαq expression in T cells from SLE patients was associated with disease severity (as per SLE Disease Activity Index), the presence of lupus nephritis, and expression of Th1, Th2 and Th17 cytokines. In keeping with clinical results, T-helper cell subsets (Th1, Th2 and Th17) were over-represented in Gαq knockout mice. In addition, Gαq expression in SLE T cells was negatively correlated with the expression of Bcl-2, an anti-apoptotic gene, and positively correlated with the expression of Bax, a pro-apoptotic gene. These data suggest that reduced Gαq levels in T cells may promote enhanced and prolonged T cell activation, contributing to the clinical manifestations of SLE.