Rapidly progressive interstitial lung disease risk prediction in anti-MDA5 positive dermatomyositis: the CROSS model.

Background: The prognosis of anti-melanoma differentiation-associated gene 5 positive dermatomyositis (anti-MDA5+DM) is poor and heterogeneous. Rapidly progressive interstitial lung disease (RP-ILD) is these patients' leading cause of death. We sought to develop prediction models for RP-ILD risk in anti-MDA5+DM patients. Methods: Patients with anti-MDA5+DM were enrolled in two cohorts: 170 patients from the southern region of Jiangsu province (discovery cohort) and 85 patients from the northern region of Jiangsu province (validation cohort). Cox proportional hazards models were used to identify risk factors of RP-ILD. RP-ILD risk prediction models were developed and validated by testing every independent prognostic risk factor derived from the Cox model. Results: There are no significant differences in baseline clinical parameters and prognosis between discovery and validation cohorts. Among all 255 anti-MDA5+DM patients, with a median follow-up of 12 months, the incidence of RP-ILD was 36.86%. Using the discovery cohort, four variables were included in the final risk prediction model for RP-ILD: C-reactive protein (CRP) levels, anti-Ro52 antibody positivity, short disease duration, and male sex. A point scoring system was used to classify anti-MDA5+DM patients into moderate, high, and very high risk of RP-ILD. After one-year follow-up, the incidence of RP-ILD in the very high risk group was 71.3% and 85.71%, significantly higher than those in the high-risk group (35.19%, 41.69%) and moderate-risk group (9.54%, 6.67%) in both cohorts. Conclusions: The CROSS model is an easy-to-use prediction classification system for RP-ILD risk in anti-MDA5+DM patients. It has great application prospect in disease management.

Association of disease activity with depression and anxiety in systemic lupus erythematosus: A comparison of SLEDAI-2K and SLE-DAS.

OBJECTIVE: To explore the association of disease activity, as evaluated by both the Systemic Lupus Erythematosus Disease Activity Score (SLE-DAS) and the Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K), with depression and anxiety in patients with systemic lupus erythematosus (SLE). METHODS: A cross-sectional study was conducted among 85 Chinese patients with SLE. Disease activity was measured using SLEDAI-2K and SLE-DAS scoring systems. Depression and anxiety were assessed using Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder Scale-7 (GAD-7), respectively. Multivariate logistic regression analysis was performed to evaluate the association of disease activity scores, as well as specific clinical and laboratory items, with depression and anxiety. RESULTS: There was a robust correlation between SLEDAI-2K and SLE-DAS scores in overall patients (Spearman's r = 0.764, 95% confidence interval (CI) 0.655-0.842; p< 0.001) and those with moderate-to-high disease activity (Spearman's r = 0.792, 95%CI 0.616-0.892; p< 0.0001). However, the correlation weakened for patients with mild disease activity or remission (Spearman's r = 0.450, 95%CI 0.188-0.652; p= 0.001). Multivariate logistic regression analysis did not show a significant correlation between SLEDAI-2K and SLE-DAS scores and depression/anxiety. The presence of mucosal ulcer/serositis significantly increased the risk of depression (OR = 4.472, 95%CI 1.035-19.328, p= 0.045) and anxiety (OR = 3.978, 95%CI 1.051-15.049, p= 0.042). CONCLUSION: The SLE-DAS scoring system demonstrated a comparable ability to assess disease activity in SLE compared with SLEDAI-2K. Though neither scoring system showed significant associations with depression and anxiety, the presence of mucosal ulcer/serositis markedly heightened the risk of both among SLE patients.

Gender differences in patients with anti-MDA5-positive dermatomyositis: a cohort study of 251 cases.

OBJECTIVE: To investigate the impact of sex differences on the clinical characteristics and prognosis of patients with anti-melanoma differentiation-associated gene 5-positive dermatomyositis (MDA5+ DM). METHODS: We retrospectively analyzed a cohort of 251 patients with MDA5+ DM, including 71 in the male group and 180 in the female group. A multivariate logistic regression model was built to analyze independent risk factors for RPILD in each group. An ROC curve was drawn to evaluate the predictive value of independent risk factors. Kaplan‒Meier analysis was used to compare the cumulative survival rates, while the log-rank test was used to test for significant differences between the two groups. RESULTS: Patients in the male group had a significantly higher prevalence of heliotrope rash, V sign, severe interstitial lung disease (ILD), and rapidly progressive interstitial lung disease (RPILD) than those in the female group. Anti-Ro52 positivity, high CRP level and short disease were identified as independent risk factors for RPILD in both male and female groups by multivariate logistic regression analysis. The mortality rates of males and females were 33.8% and 22.0%, respectively, and the survival time of patients in the male group was shorter than that in the female group. CONCLUSION: Male patients with MDA5+ DM exhibit an increased risk of RPILD, elevated mortality rates and reduced overall survival time compared to their female counterparts, and anti-Ro52 positivity may be an unfavorable prognostic factor for these patients. Key Points • The prevalence of solar rash, V sign, severe interstitial lung disease (ILD) and rapidly progressive interstitial lung disease (RPILD) in anti-MDA5-positive female patients was significantly lower than that in male patients. • Positive Anti-Ro52, high CRP level, and short course of disease were independent risk factors for RPILD in both men and women. • Female patients exhibited a lower mortality rate than male patients (22.0% vs 33.8%) and demonstrated longer survival time.

Association of anti-Ro52 antibody with depression and anxiety in patients with connective tissue diseases: an observational, single-centre, cross-sectional study.

OBJECTIVES: To explore the risk factors of anxiety and depression, especially their association with serum autoantibodies, in patients with connective tissue diseases (CTDs). METHODS: Three hundred and fifty-two inpatients with CTDs were recruited and their demographic, serological and imaging data were collected through the medical record system. Depression and anxiety were assessed by the Patient Health Questionnaire-9 (PHQ-9) and the Generalized Anxiety Disorder-7 Scale (GAD-7) respectively. Analysis of variance (ANOVA), rank sum test, chi-square test and logistic regression were performed to investigate risk factors for depression and anxiety. RESULTS: The prevalence of depression (PHQ-9 ≥ 5) and anxiety (GAD-7 ≥5) in CTD patients was significantly higher than that in the Chinese general population (depression: 44.3% vs. 32.2%, anxiety: 39.5% vs. 22.2%). Sleep time was a protective factor for both depression and anxiety (OR=0.734, 95% CI: 0.616~0.874, p<0.001 and OR=0.684, 95% CI: 0.559~0.835, P<0.001, respectively) while anti-Ro52 antibody was a risk factor for them (OR=5.466, 95% CI: 2.978~10.032, p<0.001 and OR=4.075, 95% CI: 2.073~8.010, p<0.001, respectively). Further analysis showed that anti-Ro52 antibody was a risk factor for depression and anxiety in all four subgroups, namely SLE, SS, RA, and other CTDs. CONCLUSIONS: Anti-Ro52 antibody is probably a risk factor for depression and anxiety in patients with connective tissue diseases. CTD patients with the presence of anti-Ro52 antibody are more prone to depression and anxiety than those without it.

Coexistence of Anti-Ro52 Antibodies in Anti-MDA5 Antibody-Positive Dermatomyositis Is Highly Associated With Rapidly Progressive Interstitial Lung Disease and Mortality Risk.

OBJECTIVE: Interstitial lung disease (ILD) is a common extramuscular complication contributing to significant morbidity and mortality in patients with dermatomyositis (DM) who are positive for antimelanoma differentiation-associated gene 5 antibody (anti-MDA5+). We conducted this study to investigate the association of anti-Ro52 antibodies with clinical characteristics and prognosis in patients with anti-MDA5+ DM. METHODS: We assessed a cohort of 246 patients with anti-MDA5+ DM. To calculate hazard ratios and 95% CIs for rapidly progressive ILD (RP-ILD) and death while controlling for potential confounders, variables selected by univariate Cox regression analysis were included in a multivariate Cox regression model with the stepwise forward-selection method. A 2-tailed analysis with P < 0.05 was considered to be statistically significant. RESULTS: A total of 246 patients with anti-MDA5+ DM were enrolled; 70 patients were male, and the patient group had an average age of 53.1 (12.4) years. Anti-Ro52 was present in 64.2% (158/246) patients. Patients with anti-MDA5+ DM who were positive for anti-Ro52 had a higher rate of RP-ILD (log-rank P < 0.001) and a higher mortality rate (log-rank P = 0.01). For patients with anti-MDA5+ DM who were positive for anti-Ro52, those with a short disease course and high inflammation were at increased risk of RP-ILD and death. The appearance of active rash was an independent protective factor of death. CONCLUSION: Anti-Ro52 antibodies were highly prevalent in patients with anti-MDA5+ DM, and their coexistence correlated with a higher rate of RP-ILD and mortality. Patients with a short disease course, with increased inflammation, and without rash were more likely to have a poor prognosis.

Identification of Three Different Phenotypes in Anti-Melanoma Differentiation-Associated Gene 5 Antibody-Positive Dermatomyositis Patients: Implications for Prediction of Rapidly Progressive Interstitial Lung Disease.

OBJECTIVE: There is substantial heterogeneity among the phenotypes of patients with anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5+) dermatomyositis (DM), hindering disease assessment and management. This study aimed to identify distinct phenotype groups in patients with anti-MDA5+ DM and to determine the utility of these phenotypes in predicting patient outcomes. METHODS: A total of 265 patients with anti-MDA5+ DM were retrospectively enrolled in the study. An unsupervised hierarchical cluster analysis was performed to characterize the different phenotypes. RESULTS: Patients were stratified into 3 clusters characterized by markedly different features and outcomes. Cluster 1 (n = 108 patients) was characterized by mild risk of rapidly progressive interstitial lung disease (RPILD), with the cumulative incidence of non-RPILD being 85.2%. Cluster 2 (n = 72 patients) was characterized by moderate risk of RPILD, with the cumulative incidence of non-RPILPD being 73.6%. Patients in cluster 3 (n = 85 patients), which was characterized by a high risk of RPILD and a cumulative non-RPILD incidence of 32.9%, were more likely than patients in the other 2 subgroups to have anti-Ro 52 antibodies in conjunction with high titers of anti-MDA5 antibodies. All-cause mortality rates of 60%, 9.7%, and 3.7% were determined for clusters 3, 2, and 1, respectively (P < 0.0001). Decision tree analysis led to the development of a simple algorithm for anti-MDA5+ DM patient classification that included the following 8 variables: age >50 years, disease course of <3 months, myasthenia (proximal muscle weakness), arthritis, C-reactive protein level, creatine kinase level, anti-Ro 52 antibody titer, and anti-MDA5 antibody titer. This algorithm placed patients in the appropriate cluster with 78.5% accuracy in the development cohort and 70.0% accuracy in the external validation cohort. CONCLUSION: Cluster analysis identified 3 distinct clinical patterns and outcomes in our large cohort of anti-MDA5+ DM patients. Classification of DM patients into phenotype subgroups with prognostic values may help physicians improve the efficacy of clinical decision-making.

Time-dependent changes in RPILD and mortality risk in anti-MDA5+ DM patients: a cohort study of 272 cases in China.

OBJECTIVES: Anti-melanoma differentiation-associated gene 5 positive (anti-MDA5+) DM has a close relationship with rapidly progressive interstitial lung disease (RPILD) and is associated with high mortality. However, data regarding the time-dependent risk of RPILD and deaths during disease progression are limited. We conducted this study to investigate whether the risk of RPILD and death were time-dependent or not in anti-MDA5+ DM. METHODS: We assessed a cohort of 272 patients with anti-MDA5+ DM. The clinical characteristics of patients with anti-MDA5+ were collected, and COX regression was used to analyse independent risk factors for RPILD and death. We also described changes in risk of RPILD and death over time and their potential clinical implications. RESULTS: There were 272 anti-MDA5+ DM patients enrolled in this study. According to the multivariate cox regression analysis, short disease course, high CRP level, anti-Ro52 positive and anti-MDA5 titre (++∼+++) were independent risk factors of RPILD. High creatine kinase level, high CRP level and RPILD were independent risk factors for death, and >90% RPILD and 84% mortality occurred in the first 6 months after disease onset. Notably, the first 3 months is a particularly high-risk period, with 50% of RPILD and 46% of deaths occurring. Hazards regarding RPILD and mortality diminished over time during a median follow-up of 12 months. CONCLUSION: These results suggest significant, time-dependent changes in RPILD and mortality risk in anti-MDA5+ DM patients, providing a cut-off time window to estimate disease progression and poor prognosis.

Increased interleukin-11 associated with disease activity and development of interstitial lung disease in patients with rheumatoid arthritis.

OBJECTIVES: To investigate the association of serum interleukin-11 (IL-11) with disease activity and occurrence of interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA). METHODS: One hundred and six RA patients were included, including 31 with ILD. All patients were divided into two groups according to the 28-joint Disease Activity Score (DAS28), active-disease group (DAS28>3.2) and target-achieved group (DAS28≤3.2). Serum IL-11 was detected by ELISA. Serum autoantibodies [anticitrullinated protein antibody (ACPA) and rheumatoid factor (RF)], inflammatory markers [C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR)], and complete blood count were measured with routine methods. RESULTS: Serum IL-11 was upregulated in RA patients compared with healthy controls (HC), and increased more significantly in patients with ILD (RA-ILD) than patients without ILD (RA-nonILD). In both RA-ILD and RA-nonILD patients, serum level of IL-11 was higher in the active-disease group than that in the target-achieved group. Pearson correlation analysis confirmed that IL-11 was positively correlated with DAS28. No significant correlation was found between serum level of IL-11 and ACPA or RF. IL-11 was positively correlated with ESR and CRP levels and PLT count in RA patients. CONCLUSIONS: IL-11 was found to be involved in the development of arthritis and ILD in RA patients, and might constitute a potential target for the treatment of RA-ILD.

Febuxostat in the treatment of gout patients with low serum uric acid level: 1-year finding of efficacy and safety study.

To retrospectively analyze the efficacy and safety of febuxostat on gout patients with low serum uric acid level. A study was conducted in Nanjing First Hospital from October 2015 to September 2016. Thirty nine acute gouty arthritis patients from the emergency and outpatient department were included. Patients met the 2015 Gout Classification Criteria revised by American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) and had urate deposition around the joints detected by dual-energy computerized tomography (DECT). Patients whose serum uric acid (SUA) were between 5.0 and 7.0 mg/dl (300-420 µmol/l) received febuxostat treatment to maintain the SUA level between 3.0 and 5.0 mg/dl for 1 year. Efficacy and safety of febuxostat were observed during the process. Three of 39 subjects were excluded because of adverse events (AEs) after receiving an initial febuxostat treatment for 2 months. Thirty six subjects were enrolled. The mean SUA level was reduced significantly from 6.51 ± 0.28 mg/dl at baseline to 4.24 ± 0.38 mg/dl and SUA of all subjects decreased by 34.8% compared with baseline. After 1-year treatment, the volume of tophus was reduced approximately 62.8%. Serum creatinine decreased stepwise in 8 gout patients with chronic kidney diseases from 162.5 ± 9.2 µmol/l to 131.4 ± 11.0 µmol/l. Two months after initiation of treatment, the number of gout flares began to markedly decrease and almost did not occur after 1 year. After the 1-year treatment of febuxostat, the average SUA level declined significantly, and the renal function improved gradually. There was nearly complete abolition of gout flares by the end of the study. Tophi resolved markedly compared with baseline as assessed by DECT. Furthermore, only a few people experienced adverse events. Febuxostat has a notable effect for gout patients in the lower SUA level range.

(99) Tc-methylene diphosphonate improves rheumatoid arthritis disease activity by increasing the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs.

AIM: γδ T cells exhibit important functions in the pathogenesis of rheumatoid arthritis (RA). In recent years, numerous studies harnessed the γδ T cell-activating capacity of aminobiphosphonates for the treatment of malignant tumors. As (99) Tc-methylene diphosphonate ((99) Tc-MDP) has long been widely used for the treatment of RA in China with good efficacy, we are interested in whether this drug exerts its therapeutic effect on RA by modulating peripheral γδ T cells of RA patients. OBJECTIVES: To investigate the effect of (99) Tc-MDP on the frequency of γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs in the peripheral blood of patients with active RA. METHODS: Nineteen patients with active RA were treated with (99) Tc-MDP intravenously at a dose of 20 µg/day consecutively for 10-14 days. Before and after treatment, the main clinical and laboratory parameters for each patient were evaluated. The frequency of CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs was detected by flow cytometry. Serum levels of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 and transforming growth factor (TGF)-ß were measured with enzyme-linked immunosorbent assay. RESULTS: After intravenous (99) Tc-MDP therapy, the frequency of peripheral CD3(+) γδ(+) T cells and CD4(+) CD25(+) Foxp3(+) Tregs were significantly elevated, paralleled with decreased serum levels of TNF-α and IL-6 and increased level of serum TGF-ß. The elevation of peripheral CD3(+) γδ(+) T cells was positively correlated with increased serum TGF-ß and decreased disease activity. CONCLUSION: (99) Tc-MDP may improve the activity of RA through upregulating the frequency of peripheral γδ T cells and CD4(+) CD25(+) Foxp3(+) Tregs as well as affecting the serum cytokine environment by increasing TGF-ß and decreasing TNF-α and IL-6.

Allogeneic mesenchymal stem cells inhibited T follicular helper cell generation in rheumatoid arthritis.

T follicular helper (Tfh) cells provide help for antigen-specific B cells. We have previously shown that Tfh cell frequency was increased and associated with auto-antibodies in patients with rheumatoid arthritis (RA), suggesting a possible involvement of Tfh cells in its pathogenesis. Mesenchymal stem cells (MSCs) represent a promising alternative cell therapy for RA by modulating T and B cell activation and proliferation. However, it remains unknown whether MSCs have immunoregulation on Tfh cells. In this paper, we have demonstrated that allogeneic MSCs could suppress Tfh cell differentiation in RA patients partly via the production of indoleamine 2,3-dioxygenase (IDO). IFNγ generated from Tfh cell differentiation system induced IDO expression on MSCs. MSCs transplantation (MSCT) into collagen-induced arthritis (CIA) mice prevented arthritis progression by inhibiting both the number and function of Tfh cells in vivo. These findings reveal a novel suppressive function of MSCs in Tfh cells, which has implication in understanding the underlying mechanisms of the immunotherapeutic effects of MSCs on RA patients.

Umbilical cord mesenchymal stem cells inhibit the differentiation of circulating T follicular helper cells in patients with primary Sjögren's syndrome through the secretion of indoleamine 2,3-dioxygenase.

OBJECTIVE: The aim of this study was to investigate the effect of umbilical cord mesenchymal stem cells (UC-MSCs) on circulating T follicular helper (cTfh) cells in primary SS (pSS) patients. METHODS: The percentage of CXCR5(+)PD-1(+)CD4(+) T cells in peripheral blood mononuclear cells (PBMCs) was analysed by flow cytometry. PBMCs were co-cultured with UC-MSCs by cell-to-cell contact or in a trans-well system. Naive CD4(+) T cells were isolated from PBMCs and then co-cultured with UC-MSCs under Tfh cell-polarizing conditions. The percentage of CXCR5(+)PD-1(+)CD4(+) T cells, carboxyfluorescein succinimidyl ester (CFSE) fluorescence intensity and annexin V were determined by flow cytometric analysis. Real-time PCR and Luminex cytokine assay were performed to detect mRNA expression and supernatant protein levels. The activity of indoleamine 2,3-dioxygenase (IDO) was measured by HPLC. RESULTS: Increased frequency of cTfh cells was found in pSS patients and was positively correlated with serum anti-La/SSB levels and the European League Against Rheumatism SS Disease Activity Index score. In vitro, UC-MSCs suppressed the differentiation and proliferation of cTfh cells. Real-time PCR analysis showed significantly higher IDO mRNA expression on UC-MSCs when co-cultured with naive CD4(+) T cells under Tfh cell-polarizing conditions in pSS patients. However, IDO mRNA expression on UC-MSCs was only a little higher when UC-MSCs were co-cultured with naive CD4(+) T cells in a trans-well system. In addition, HPLC showed increased IDO enzymic activity in the supernatant of UC-MSCs co-cultured with naive CD4(+) T cells under Tfh cell-polarizing conditions in pSS. The addition of the IDO inhibitor 1-MT partly reversed the suppressive effect of UC-MSCs on the differentiation of cTfh cells. CONCLUSION: These results suggest an inhibitory effect of UC-MSCs on the differentiation of cTfh cells via the secretion of IDO, and soluble factors secreted by activated CD4(+) T cells might contribute to IDO secretion by UC-MSCs.

TL1A increased the differentiation of peripheral Th17 in rheumatoid arthritis.

The interaction between TNF-like protein 1A (TL1A) and its receptors, death receptor-3 (DR3) may be involved in the pathogenesis of rheumatoid arthritis (RA) through the regulation of Th17. Our data here showed that TL1A could significantly promote Th17 differentiation and RORc mRNA expression from naive T cells and enhance IL-17A level in cell supernatant in RA patients. Anti-TNF-α treatment had suppressive effects on TL1A-mediated Th17 differentiation and RORc mRNA expression. In addition, The percentage of peripheral CD4+DR3+T cells of RA was significantly higher than that of healthy controls (HC), and this increased percentage of CD4+DR3+T cells was obviously up-regulated when stimulated with anti-CD3 and anti-CD28 antibody in RA patients. However, anti-CD3 and anti-CD28 antibody stimulation did not increase the percentage of CD4+DR3+IL-17A+T cells in RA patients. These results suggested that TL1A could promote Th17 differentiation in RA via the activation of RORc, and this effect may be mediated by the binding of TL1A with DR3.

Possible novel biomarkers of organ involvement in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is characterized by excessive production of various autoantibodies, which play important roles in the pathogenesis of SLE. Apart from classical autoantibodies such as anti-double stranded DNA antibody (anti-dsDNA), anti-Smith antibody (anti-Sm), and anti-phospholipid antibody (APL), recent studies focus on some novel autoantibodies including anti-complement (C) 1q antibody (anti-C1q), which is closely correlated with lupus nephritis; anti-N-methyl-D-asparate receptor antibody (NMDAR), which mediates neuropsychiatric manifestations in SLE to some extent; anti-galectin, which is involved in secondary anti-phospholipid syndrome (APS) in SLE; and anti-Müllerian hormone (AMH), which represents a more specific biomarker for subclinical ovarian damage caused by the disease itself or cytotoxic drugs in SLE patients. Correlation of these autoantibodies with disease activity and organ involvement of SLE may help to evaluate disease severity, efficacy of treatment, and long-term prognosis. Furthermore, combined measurement of a variety of autoantibodies is supposed to be more valuable in estimating disease activity and severity.

Elevated apoptosis and impaired proliferation contribute to downregulated peripheral γ δ T cells in patients with systemic lupus erythematosus.

OBJECTIVE: To investigate the frequency of peripheral γ δ T cells in patients with systemic lupus erythematosus (SLE) and its correlation with disease activity and to analyze the apoptotic status, proliferation ability, and intracellular cytokine profile of these cells. METHODS: Flow cytometry was performed to detect the percentage and intracellular cytokine expression of peripheral γ δ T cells from SLE patients. Annexin-V/PI double staining was applied to determine the proportion of apoptotic γ δ and CD3(+) T cells. γ δ T cell proliferation was analyzed by CFSE labeling technique. RESULTS: The percentage and absolute number of γ δ T cells were remarkably decreased in active SLE patients compared to those in inactive patients and healthy controls, with γ δ T cell count negatively correlated with disease activity. Compared with healthy controls, peripheral γ δ T cells from active SLE patients exhibited higher apoptotic rate and lower proliferation ability, as well as elevated expression of intracellular IFN-γ , IL-4, IL-10, and TGF- ß , but not IL-17 or Foxp3. CONCLUSION: Decreased γ δ T cells in the peripheral blood of SLE patients might be caused by upregulated apoptosis and downregulated cell proliferation. These γ δ T cells may secret both pro- and anti-inflammatory cytokines to perform their functions in SLE.

High-dose methylprednisolone pulse therapy upregulated FcγRIIb expression on B cells in primary Sjögren's syndrome patients with thrombocytopenia.

Abnormalities in B cell are characteristic feature of primary Sjögren's syndrome (pSS). As FcγRIIb is a key regulator of B cells, the objective of this study is to investigate the role of the inhibitory receptor FcγRIIb in B cells from pSS patients, and whether glucocorticoid can affect B cell subpopulations or FcγRIIb expression. Thirty pSS patients and 15 healthy controls were enrolled in this study. The results showed that the percentage of memory CD19(+)CD27(+) B cells was significantly lower in pSS patients compared to in healthy controls. FcγRIIb expression on memory CD19(+)CD27(+) B cells from active pSS patients was significantly reduced compared with those from inactive or healthy controls. The level of FcγRIIb on memory CD19(+)CD27(+) B cells from active pSS patients was negatively correlated with anti-SSA antibody titers and Sjögren's syndrome disease activity index. After a high-dose methylprednisolone pulse therapy for 3 days, FcγRIIb expression on memory B cells was upregulated, with the raised level of platelets. In vitro, dexamethasone could elevate FcγRIIb expression on B cells of pSS patients in a dose-dependent manner. Taken together, our data suggest that the upregulation of FcγRIIb may be expected to be a new therapeutic strategy in pSS patients.

Roles of γδ T cells in the pathogenesis of autoimmune diseases.

γδ T cells are a minor population of T cells that express the TCR γδ chains, mainly distributed in the mucosal and epithelial tissue and accounting for less than 5% of the total T cells in the peripheral blood. By bridging innate and adaptive immunity, γδ T cells play important roles in the anti-infection, antitumor, and autoimmune responses. Previous research on γδ T cells was primarily concentrated on infectious diseases and tumors, whereas their functions in autoimmune diseases attracted much attention. In this paper, we summarized the various functions of γδ T cells in two prototypical autoimmune connective tissue diseases, that is, SLE and RA, elaborating on their antigen-presenting capacity, secretion of proinflammatory cytokines, immunomodulatory effects, and auxiliary function for B cells, which contribute to overproduction of proinflammatory cytokines and pathogenic autoantibodies, ultimately leading to the onset of these autoimmune diseases. Elucidation of the roles of γδ T cells in autoimmune diseases is not only conducive to in-depth understanding of the pathogenesis of these diseases, but also beneficial in providing theoretical support for the development of γδ T-cell-targeted therapy.

A regulatory effect of IL-21 on T follicular helper-like cell and B cell in rheumatoid arthritis.

INTRODUCTION: Interleukin (IL)-21 is a member of type I cytokine family. Recent studies indicate that IL-21 can promote T follicular helper (Tfh) cell differentiation and survival, a specialized T cell subset which provides help for B cell. It can also regulate the activation, proliferation and differentiation of human B cell and immunoglobulin (Ig) production as well as isotype switching of plasma cell. Rheumatoid arthritis (RA) is characterized by auto-antibodies overproduction such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibody, suggesting a pivotal role of Tfh cell and B cell in the pathogenesis of RA. This study aimed to investigate whether IL-21 had a regulatory effect on Tfh cell and B cell in RA. METHODS: Serum IL-21 concentrations were measured by ELISA. The correlations between serum IL-21 levels and clinical features of RA patients were analyzed by Spearman's rank test. The percentages of Tfh-like cells, IL-21 receptor (R) expression on Tfh-like cells and B cells in peripheral blood (PB) were analyzed by flow cytometry. Peripheral blood mononuclear cells (PBMC) were stimulated by rIL-21 (100 ng/ml) in the presence or absence of anti-CD40 and/or anti-IgM, and changes of IL-21R, activation-associated surface markers (CD25, CD69 and CD40), the proliferation, apoptosis and differentiation of B cells were analyzed by flow cytometry. Production of IgG and IgM in the culture supernatants was determined by ELISA. RESULTS: The results showed that the serum IL-21 levels in RA patients were significantly higher than that of healthy controls (HC). IL-21 concentrations were positively correlated with 28-joint count disease activity score (DAS28) and anti-CCP antibody in RA patients with high IL-21 levels. Furthermore, the frequencies of peripheral CXCR5+PD-1+CD4+ Tfh-like cells markedly increased in RA patients and the percentages of Tfh-like cells were positively correlated with DAS28 and anti-CCP antibody levels. Moreover, elevated IL-21 levels were also correlated with the frequencies of Tfh-like cells. IL-21R expression on both Tfh-like cells and B cells were significantly enhanced in RA patients. In cultures vitro, exogenous IL-21 upregulated IL-21R expression and activation-associated surface markers on B cells and promoted more B cell proliferation in RA than in HC. This IL-21-mediated effect could be reversed by IL-21R-specific neutralizing antibody. Importantly, IL-21 promoted more differentiation of B cell into plasmablast and higher levels of IgG and IgM production in RA than in HC. CONCLUSIONS: Increased serum IL-21 levels in RA patients correlate with DAS28, anti-CCP antibody and frequencies of Tfh-like cells. IL-21 supports B cell activation, proliferation and antibody secretion via IL-21R pathway. Thus, IL-21 may be involved in the pathogenesis of RA and antagonizing IL-21 could be a novel strategy for the therapy of RA.