Expansion of exhausted CD8+ T cells associates with increased pulmonary fungal infection risk in anti-melanoma differentiation associated gene 5 dermatomyositis.

OBJECTIVES: Anti-MDA5+ dermatomyositis was associated with poor prognosis due to the high incidence of rapid progressive interstitial lung disease, pulmonary infection. The aim of this study is to investigate the abundance and clinical relevance of exhaustion markers on peripheral CD8 T cells from patients with idiopathic inflammatory myopathy (IIM). METHODS: Twenty-nine healthy controls (HCs) and 71 patients with IIM were enrolled, including 42 with anti-MDA5+ and 18 with anti-MDA5- dermatomyositis (DM) and 11 with anti-synthetase syndrome (ASS). Flow cytometry was applied to detect PD-1, TIM-3 and LAG-3 in CD8 T cells. The clinical associations of the CD8 T cell exhaustion phenotype in patients with anti-MDA5+ DM were analysed. RESULTS: CD8 T cells from patients with anti-MDA5+ DM showed significantly increased LAG-3, TIM-3 and PD-1 compared to those from patients with anti-MDA5- IIM (18 with anti-MDA5- DM and 11 with ASS) or HCs (adjusted p all < 0.05). CD8 T cells with distinct exhaustion levels were all significantly increased in anti-MDA5+ DM patients compared with HCs (p all < 0.05). Patients with high level of PD-1+ TIM-3+LAG-3+ CD8+ T cells had a significant higher incidence of pulmonary fungal infections but lower counts of CD4+ and CD8+ T cells. ROC analysis revealed that the frequency of PD-1+TIM-3+LAG-3+CD8+ T cell significantly predicted pulmonary fungal infections (area under the curve: 0.828). CONCLUSIONS: CD8 T cells from patients with anti-MDA5+ DM show significant exhausted phenotype, and increased exhausted CD8 T cells were associated with high risk of pulmonary fungal infection.

Evaluation and validation of the prognostic value of anti-MDA5 IgG subclasses in dermatomyositis-associated interstitial lung disease.

OBJECTIVE: To investigate the association between the anti-melanoma differentiation associated gene 5 (MDA5) IgG subclasses and prognosis of patients with dermatomyositis (DM)-associated interstitial lung disease (ILD). METHODS: This retrospective study included 122 anti-MDA5 positive DM-ILD patients admitted from October 2017 to October 2020 as training cohort, and additional 68 patients from August 2014 to September 2017 as validation cohort. The levels of anti-MDA5 total IgG and IgG subclasses were measured using in-house enzyme-linked immunosorbent assays, and analysed in association with the patient prognosis. RESULTS: In the training cohort, the concentrations of anti-MDA5 IgG1 and IgG3 in non-survivors were significantly higher than in survivors (P < 0.05), whereas there were no significant differences in the IgG2 and IgG4 levels. Kaplan-Meier survival analysis revealed that the levels of anti-MDA5 total IgG, IgG1 and IgG3 were associated with mortality (P < 0.05). Multivariate analysis revealed anti-MDA5 IgG1 >13 U/ml and anti-MDA5 IgG3 >11 U/ml were independent risk factors for death of DM-ILD patients (P < 0.05). Anti-MDA5 IgG1 was confirmed as an independent risk factor in the validation cohort, while anti-MDA5 IgG3 was not. Anti-MDA5 IgG1 showed greater discriminable power for patient prognosis (Youden index 0.494) than anti-MDA5 total IgG, IgG3, or the combination of IgG1 and IgG3 (Youden index 0.356, 0.32 and 0.447, respectively). CONCLUSION: Anti-MDA5 IgG1 and IgG3 are significantly associated with poor prognosis in DM-ILD patients, and anti-MDA5 IgG1 is more efficient as a prognostic biomarker in DM-ILD patients.

Infection is not rare in patients with idiopathic inflammatory myopathies.

OBJECTIVES: To assess the prevalence and characteristics of infections in patients with idiopathic inflammatory myopathies (IIM) and analyse risk factors for infection using clinical presentation and biochemical findings of IIM. METHODS: Retrospective review of the medical records of patients with IIM followed up in a single medical centre from January 2008 to January 2018. RESULTS: Of the 779 patients with IIM, 215 (27.6%) suffered from infections. The prevalence of infection in dermatomyositis (DM) (29.8%) was more than polymyositis (PM) (18.5%). The lung was the most common infection site (66.5%). Multivariate analyses demonstrated that methylprednisolone pulse (MP) (OR=3.22; 95% CI=1.60 - 6.48; p=0.001), age of onset >50 years (OR=1.02; 95% CI=1.00 - 1.03; p=0.011), anti-melanoma differentiation-associated gene 5 (MDA5) antibody (OR=1.93; 95% CI=1.20 - 3.11; p=0.007), lymphocyte count <1200/mm3 (OR=2.85; 95% CI=1.89 - 4.30; p<0.001), and interstitial lung diseases (ILD) (OR=2.03; 95% CI=1.30 - 3.71; p=0.002) are independent risk factors for infection. Survival analysis demonstrated that the three-year survival rate in the infection group was lower than the no-infection group (75.3% vs. 94.7%, p < 0.001). CONCLUSIONS: Among hospitalised individuals with IIM, infection is frequent and the leading cause of mortality. The anti-MDA5 antibody, lymphopenia, ILD, old age, and treatment with MP are contributing factors in the development of infections in patients with IIM.

Clinical characteristics of anti-isoleucyl-tRNA synthetase antibody associated syndrome and comparison with different patient cohorts.

OBJECTIVES: This study aimed to analyse the clinical features of anti-isoleucyl-tRNA synthetase (OJ) antibodies in Chinese patients and to compare with previously published cohorts. We reviewed the clinical data of anti-OJ antibody positive patients, including their long-term follow-up. RESULTS: Anti-OJ antibodies were present in 10 of 1269 (0.8%) patients with idiopathic inflammatory myopathies (IIMs), and 10/320 (3.1%) patients with anti-synthetase syndrome (ASS). Of the anti-OJ antibody-positive patients, 90% had interstitial lung disease (ILD), of whom three (30%) developed rapidly progressive ILD (RP-ILD). Half (50%) of the patients were febrile and developed myocardial involvement; 40% of patients experienced myositis, mechanic's hands and arthritis. Compared to the anti-Jo-1 group, the levels of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) in the anti-OJ antibody-positive group were higher (p<0.05). From a review of the literature regarding the clinical features of anti-OJ, fever was more common in the eastern cohort (41.7% vs. 8.3%, p=0.002), whereas patients in western countries were more likely to develop arthritis (20.9% vs. 58.1%, p=0.001). With complete follow-up of the present cohort, 80% improved with treatment, including one patient who underwent lung transplant. CONCLUSIONS: The anti-OJ antibody occurred infrequently in Chinese patients, ILD was the major clinical feature, but myocardial injury was also a prominent associated complication. Anti-OJ positive patients were responsive to treatment.

Identification of a novel autoantibody against heat shock factor 1 in idiopathic inflammatory myopathy.

OBJECTIVES: Myositis autoantibodies show great utility in the diagnosis and clinico-serological phenotyping of idiopathic inflammatory myopathy (IIM). We identified a novel autoantibody against heat shock factor 1 (HSF1) and further evaluated its disease specificity and clinical significance in IIM patients. METHODS: A human protein microarray was used to identify autoantibodies in myositis sera. ELISA, immunoblot and dot blot assays were applied to examine anti-HSF1 autoantibodies in IIM patients and controls. Immunofluorescence was used to detect HSF1 expression in muscle tissues. RESULTS: Anti-HSF1 was identified as a novel autoantibody by protein microarray and the seroreactivity was confirmed by immunoprecipitation, ELISA, immunoblot and dot blot assays. Anti-HSF1 autoantibodies were present in 64/581 (11.0%) IIM, 4/37 (10.8%) rheumatoid arthritis, 5/40 (12.5%) primary Sjögren's syndrome, 2/40 (5%) systemic lupus erythematosus, while largely negative in healthy controls. Anti-HSF1 autoantibodies were significantly associated with pruritus, hypergammaglobulinaemia, and elevated erythrocyte sedimentation rate in IIM patients. Anti-HSF1 autoantibodies were more prevalent in cancer-associated myositis (CAM) compared to non-CAM patients (17.2% vs. 7.5%, p=0.009), nevertheless were undetectable in cancer controls. Meanwhile, cross-sectional and longitudinal analyses revealed positive correlations between anti-HSF1 levels and disease activity in IIM patients without cancer. Additionally, increased expression of HSF1 was found in regenerating muscle cells of myositis muscle tissues. CONCLUSIONS: These data reveal anti-HSF1 as a new autoantibody associated with CAM in IIM. The autoimmunity against HSF1 may be involved in the immunopathogenesis of myositis.

Increased Levels of Soluble CD206 Associated with Rapidly Progressive Interstitial Lung Disease in Patients with Dermatomyositis.

OBJECTIVE: Soluble CD206 (sCD206) is considered a macrophage activation marker, and a previous study proved it as a potential biomarker to predict the severity of anti-melanoma differentiation-associated gene 5- (anti-MDA-5-) positive dermatomyositis- (DM-) associated interstitial lung disease (ILD). To investigate the role of sCD206 in various subtypes of DM, we evaluated the serum level of sCD206 in patients with different myositis-specific autoantibodies besides anti-MDA-5 and clarified its clinical significance. METHODS: Commercial enzyme-linked immunosorbent assay kits were used to detect serum concentrations of sCD206 in 150 patients with DM and 52 healthy controls (HCs). Correlations between sCD206 levels and clinical features, laboratory examinations, and pulmonary function test parameters were analysed. RESULTS: The median concentrations of serum sCD206 in DM patients were significantly higher than those in HCs (p < 0.0001). Furthermore, median sCD206 levels were elevated in patients with ILD (p = 0.001), especially in those with rapidly progressive ILD (RP-ILD) (p < 0.0001). In addition, sCD206 levels were negatively correlated with the pulmonary function test results, including the percent predicted forced vital capacity (r = -0.234, p = 0.023), percent predicted forced expiratory volume in one second (r = -0.225, p = 0.030), and percent predicted carbon monoxide diffusion capacity (r = -0.261, p = 0.014). Age- and gender-adjusted multivariable analysis showed that sCD206 was an independent prognostic factor for RP-ILD in patients with DM. A longitudinal study showed that sCD206 levels were positively correlated with the physician global assessment visual analog scale scores (ß = 54.201, p = 0.001). CONCLUSION: Serum sCD206 levels were significantly increased in patients with DM and significantly associated with RP-ILD, suggesting that sCD206 is an important biological predictor of RP-ILD in patients with DM.

[The levels and clinical significance of serum B cell activating factor in Chinese patients with polymyositis or dermatomyositis].

OBJECTIVES: To investigate serum levels of B cell activating factor (BAFF) in Chinese patients with polymyositis (PM) or dermatomyositis (DM), and analyze the correlation of BAFF with autoantibodies and clinical phenotypes. METHODS: Serum BAFF levels of 28 PM patients and 30 DM patients (study group), and 25 matched healthy controls (control group) were measured by ELISA. Serum anti-Jo-1 antibody levels were also measured by ELISA in all the subjects. The results of the two groups were compared by unpaired t test and the relevance was analyzed by Pearson's correlation analysis. RESULTS: Serum levels of BAFF in PM/DM patients were significantly higher compared to healthy controls (P = 0.000), but there was no statistically significant difference between the PM and DM patients (P > 0.05). Patients with interstitial lung disease (ILD) had significantly higher serum BAFF level than the patients without ILD (P = 0.000) or the controls (P = 0.000). Serum BAFF levels of patients with positive anti-nuclear antibody (ANA) were significantly higher than those with negative ANA (P = 0.003). For patients with anti-Jo-1 antibodies, the serum BAFF levels were correlated with the serum concentration of anti-Jo-1 antibodies (r = 0.799, P = 0.006). CONCLUSIONS: Serum levels of BAFF are increased in Chinese PM/DM patients. These findings indicate that BAFF may be possibly enrolled in the pathogenesis of PM/DM. Detecting serum BAFF levels could have some implication for the diagnosis and treatment of PM/DM.

[Measurement and clinical significance of serum monocyte chemoattractant protein-1 in patients with polymyosits/dermatomyosits].

OBJECTIVE: To analyze the correlated clinical significance by testing the serum monocyte chemoattractant protein-1 (MCP-1) levels of patients with polymyositis/dermatomyositis (PM/DM). METHODS: The sera from 100 adult PM/DM patients, 20 patients with pulmonary infection and 42 healthy controls were selected. The serum MCP-1 concentrations were detected by enzyme-linked immunosorbent assay (ELISA). The correlations between serum MCP-1 levels and clinical features or laboratory examinations of PM/DM patients were investigated. RESULTS: The serum levels of MCP-1 were (1 869 ±1 590) ng/L, (1 349±1 303) ng/L, (493±255) ng/L and (256±144) ng/L in PM/DM patients with interstitial lung disease (ILD) and without ILD, patients with infectious lung disease and healthy controls, respectively. Serum MCP-1 levels in the PM/DM patients with ILD were significantly higher than those of the PM/DM patients without ILD, patients with infectious lung disease and healthy controls (all P values<0.01). Significant correlations were found between the elevated levels of serum MCP-1 and the presence of ILD in the patients with PM/DM (χ2=9.6, P<0.01). The sensitivity and specificity of serum abnormal MCP-1 levels for ILD in the patients with PM/DM were 60.7% and 68.2%, respectively. The incidence of fever, arthritis, decreased %DL(CO) , erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and serum ferritin were significantly higher in the MCP-1 raised group than in the MCP-1 normal group (all P values<0.005). Additionally, Spearman rank correlation analysis showed that serum MCP-1 levels were positively correlated with serum ferritin in peripheral blood in the patients with PM/DM. CONCLUSION: The levels of serum MCP-1 are significantly elevated in PM/DM and it is significantly associated with ILD complication, and may contribute to the early differentiation of ILD from lung infectious disease.

[A multicenter study of coronary artery disease and its risk factors in rheumatoid arthritis in China].

OBJECTIVE: To learn about the prevalence and risk factors of coronary artery disease (CAD) in rheumatoid arthritis (RA). METHODS: Data were obtained from a 12-month retrospective investigation of the patients with RA, randomly selected from Departments of Rheumatology and Immunology in 21 big hospitals in China. The data were collected about their social conditions, clinical conditions, medications associated with RA, such as disease modifying anti-rheumatic drugs (DMARDs), non steroidal anti-inflammatory drugs (NSAIDs), glucocorticoid, biologic agents. A nonparameter test and multivariate logistic regression analysis were performed. RESULTS: In the study, 960 patients were enrolled. The prevalence of CAD was 3.5% in China, which was obviously higher than that of normal people. The prevalence of overweight and obesity, smoking, hypertension, diabetes mellitus, hypercholesterolemia and cerebrovascular disease were 35.1%, 12.3%, 17.0%, 7.7%, 0.4% and 3.0%, respectively. Compared with the control group, the CAD group had higher age [(64.7±9.3) years vs. (52.3±14.0) years,P<0.001], more rheumatoid nodules (14.7% vs. 3.1%,P=0.005), lower rate of hydroxychloroquine (HCQ) use (5.9% vs. 22.6%,P=0.021), higher prevalence rates of lung interstitial disease (17.5% vs. 7.0%,P<0.001), diabetes mellitus and hypertension (29.4% vs. 7.0%,P<0.001; 38.2% vs. 16.2%,P=0.001). There was no obvious correlation of CAD in RA with joint deformity, rheumatoid factor (RF) titer, glucocorticoid use, hypercholesterolemia and body mass index (BMI). Multivariate analysis showed higher age, diabetes mellitus and hypertension were independent predictors of CAD, and the use of HCQ was a protective factor of CAD. CONCLUSION: The prevalence of CAD is 3.5%. Higher age, diabetes mellitus and hypertension are independent predictors of CAD, and the use of HCQ is a protective factor of CAD.

[Survey of tumor necrosis factor inhibitors application in patients with rheumatoid arthritis in China].

OBJECTIVE: To investigate the current status of tumor necrosis factor (TNF) inhibitors application in rheumatoid arthritis (RA) patients in China and to analyze the related factors. METHODS: A retrospective survey was conducted in 21 hospitals from different parts of China. The patients with RA were randomly enrolled. Data of their social backgrounds, clinical conditions, usage and adverse effects of TNF inhibitors were collected. The costs of TNF inhibitors and the indirect costs of the disease were calculated. A multivariate Logistic regression analysis was performed to analyze the factors related to TNF inhibitors application. RESULTS: In the study, 1 095 RA patients from July 2009 to November 2010 were enrolled, of whom 112 had received TNF inhibitors, representing 10.2% of the total patients. The patients who received etanercept and infliximab were 7.4% (86/1 095) of the patients and 2.4% (26/1 095), respectively. There were 0.5% of the patients (5/1 095) who had received both of the TNF inhibitors. The patients who had accepted etanercept and treatment duration for less than 3 months and 3-6 months accounted for 38.5% and 25.0% respectively, while those treated with Infliximab were 38.1%. Their health assessment questionnaire (HAQ) scores were 1.1, 0.5 and 0.1, corresponding to treatment duration of infliximab for less than 3, 3-6 and 6-9 months and those were 1.3, 1.0, 0.3 corresponding to treatment duration of etanercept, respectively. Infliximab costs were RMB 24 525.0, 69 300.0 and 96 800.0 Yuan and etanercept costs were RMB 7 394.8, 9 158.6, 54 910.9 Yuan, respectively. Indirect costs for RA patients who accepted infliximab for less than 3, 3-6 and 6-9 months were RMB 365.6, 0 and 158.9 Yuan and those who accepted etanercept were RMB 2 158.4, 288.5 and 180.1 Yuan, respectively. Allergy and infection were the main side-effects of etanercept and both happened in 3.5% of all the patients. Liver damage happened in 2.3% of all the patients, while allergy and infection happened in 6.5% of all the patients who accepted infliximab. Logistic regression analysis showed that patients with higher education experience increased the odds of entering the TNF inhibitors group (OR: 1.292, 95%CI: 1.132-1.473, P=0.000). CONCLUSION: About one-tenth of RA patients in China have accepted TNF inhibitors. Higher education experience is the key factor for using TNF inhibitors.

[Sulphasalazine in patients with rheumatoid arthritis in China: a cross-sectional study].

OBJECTIVE: To investigate the medication status of rheumatoid arthritis (RA) patients and to analyze the clinical use of sulphasalazine (SSZ) and the adverse effect. METHODS: A total of 1 096 outpatients and inpatients diagnosed with RA were investigated in 21 hospitals all over China from July 2009 to December 2010, including gender, age of onset, clinical manifestations, as well as the clinical characteristics and medication status of 160 RA patients who received SSZ therapy. RESULTS: In the group of 160 patients who received SSZ, the male-to-female ratio was 1:7, The average age at onset was (46.1±15.0) years, while the average course was (9.9±7.8) years. The average dose of sulphasalazine was (1.87±0.52) g/d for a mean duration of (26.3± 14.6) months. Only 17% (27/160) of the patients received SSZ monotherapy. Methotrexate (63.1%), leflunomide (36.2%) and hydroxychloroquine (18.1%) were most commonly used combination drugs. And 36.2% (58/160) of the patients used the two-drug combination of methotrexate plus sulphasalazine .In this group, 41.9% (67/160) once used SSZ but withdrew for adverse events and other reasons, while 17.5% (28/160) withdrew for adverse events, of which the most common were gastrointestinal (8.8%), skin (3.8%) and liver toxicity (3.1%). CONCLUSION: Sulphaszlazine is not a common choice in the RA therapeutics in China, and the average dose of SSZ is lower than the standard dose of 2 to 3 g/d . The adverse events of SSZ are common; however, there are few severe adverse events or threat to life,SSZ is relatively safe in clinical practice.

[Surfactant proteins-A and D as important serum markers for interstitial lung disease in patients with polymyositis or dermatomyositis].

OBJECTIVE: To explore the possible diagnostic values of serum surfactant protein-A (SP-A) and surfactant protein-D (SP-D) for interstitial lung diseases (ILD) in patients with polymyositis or dermatomyositis (PM/DM). METHODS: Serum MCP-1 concentrations were measured by enzyme-linked immunosorbent assay (ELISA) in 100 adult PM/DM patients, 20 patients with pulmonary infection and 42 healthy controls. And the association with their clinical features and serum levels of SP-A and SP-D was analyzed. RESULTS: The serum levels of SP-A and SP-D in the PM/DM patients with ILD were both significantly higher than those without ILD and healthy controls (all P < 0.01) while there were no significance differences with those with infectious lung diseases (P > 0.05). The sensitivity of serum abnormal levels of SP-A, SP-D and combination of SP-A and SP-D for ILD in PM/DM patients were 66.1%, 64.3% and 80.0% and the specificity 72.7%, 72.7% and 70.2% respectively. The serum levels of SP-A were positively correlated with serum ferritin and C-reactive protein (CRP) and negatively with percent carbon monoxide diffusing capacity (DLCO%) (r = -0.474, P < 0.05), VC% (r = -0.404, P < 0.05) while the serum levels of SP-D were negatively correlated with circulating CD3+T cells (r = -0.244, P < 0.05) and CD4+T cells (r = -0.277, P < 0.05) in PM/DM patients. Furthermore, SP-A was an independent risk factor for death of ILD in PM/DM (OR 1.032, 95%CI 1.006 - 1.059, P < 0.05). CONCLUSION: SP-A and SP-D may be potential useful serum markers for the diagnosis of ILD in PM/DM patients. And the combined detection of SP-A and SP-D offers a higher sensitivity than either marker alone. As a risk factor, serum SP-A can predict the prognosis of PM/DM patients with ILD.

Contribution of Necroptosis to Myofiber Death in Idiopathic Inflammatory Myopathies.

OBJECTIVE: Myofiber necrosis is a significant pathologic characteristic of idiopathic inflammatory myopathies (IIMs), and its molecular mechanism is largely unknown. Necroptosis is a recently identified form of regulated necrotic cell death, and its activation might have crucial biologic consequences. The aim of the present study was to investigate the role of necroptosis in IIM muscle damage. METHODS: Western blot and immunohistochemistry analyses were performed to examine the expression of receptor-interacting protein 3 (RIP-3) and mixed-lineage kinase domain-like (MLKL) proteins in 26 IIM patients and 4 healthy controls, as well as necroptosis-related damage-associated molecular pattern molecules. Tumor necrosis factor (TNF) was used to stimulate cultured C2C12 myoblasts, and the involvement of necroptosis in cell death of C2C12 cells was studied in vitro. RESULTS: The expression of RIP-3 and MLKL proteins and their phosphorylated forms was significantly increased in the muscle tissue of IIM patients compared to that of healthy controls. The expression levels of RIP-3 and MLKL proteins were associated with the severity of muscle damage in patients with IIM. Significant colocalization of MLKL with high mobility group box chromosomal protein 1 in necrotizing myofibers was observed in muscle biopsy tissue from patients with IIM. Stimulation of C2C12 myoblasts with TNF and a pan-caspase inhibitor, Z-VAD, resulted in the overactivation of necroptosis and significantly increased necrotic cell death. Strategies involving either inhibition of necroptosis with necrostatin-1 or knockdown of MLKL expression successfully prevented necroptosis-induced cell death of C2C12 cells. CONCLUSION: These findings demonstrate that overactivated necroptosis contributes to muscle damage in IIMs and suggest that necroptosis inhibitors could represent a new therapeutic target in the treatment of IIMs.

Clinical characteristics and favorable long-term outcomes for patients with idiopathic inflammatory myopathies: a retrospective single center study in China.

BACKGROUND: Little is known about the clinical features and true survival risk factors in Chinese Han population. We conducted the current study to investigate the clinical features, long-term outcome and true potential indicators associated with mortality of idiopathic inflammatory myopathies (IIM) in China. METHODS: We restrospectvely investigated 188 patients diagnosed with IIM at our hospital from January 1986 to April 2009. The primary outcome was determined with mortality. The secondary outcomes for survival patients were organ damage and disease activity, health status, and disability, which were assessed with Myositis Damage Index, Myositis Disease Activity Assessment Visual Analogue Scales, Health Assessment Questionnaire Disability Index, and the Modified Rankin Scale, respectively. Potential prognostic factors for mortality were analyzed with the multivariate Cox regression model. RESULTS: Mean age at disease onset was 43.8 ± 15.8 years and male to female ratio was 1:2.1 in this cohort. The 1-, 5-, 10-, 15- and 20-year survival rates were 93.6%, 88.7%, 81%, 73.6% and 65.6%. The independent predicators for mortality were age at disease onset [hazard ratio (HR):1.05, 95% CI 1.02 - 1.08], presence of cancer (HR:3.68, 95%CI 1.39 - 9.74), and elevated IgA level at diagnosis (HR:2.80, 95% CI 1.16-6.74). At the end of the follow-up, 29 patients manifested drug withdrawal within an average 4.1 years (range 0.5-15.2 year), most patients (85.9%) had no disease activity and 130 patients (83.4%) had no disability. CONCLUSIONS: The long-term outcomes of IIM patients in our cohort have improved dramatically. Those patients most likely to survive had a high chance of reaching stable disease status, and obtained long-term or possibly permanent remission to a large extent.

[The expression of the type I interferon system in muscle and lung of autoimmune myositis rat model].

OBJECTIVE: To investigate the expression levels of the type I IFN system in muscle and lung of experimental autoimmune myositis (EAM) model and to evaluate whether the type I IFN system associates with the pathogenesis of the EAM model in rats. METHODS: The EAM model was established to determine creatine kinase (CK) in blood serum. The pathology of muscle and lung tissue was examined by hematoxylin-eosin staining. The concentration of type I IFN system mRNA in muscle and lung tissue was detected by real-time PCR. RESULTS: The concentration of CK in model group [(209.17 ± 91.95) IU/L] was significantly higher than that of two control groups (P < 0.05). The scores of muscle and lung in EAM model were significantly higher than that of control groups (all P < 0.05). The expression levels of the type I IFN system in muscle of EAM model were significantly higher than that of control groups (all P < 0.05). The expression levels of the type I IFN system in muscle with EAM model were positively correlated with CK and the scores of muscle (all P < 0.05). The expression levels of IFNα, IFNß, IFNαR1, signal transducer and activator of transcription 1 (STAT1), myxovirus resistance protein 1 (MX1) in lung of EAM model were significantly higher than those of control groups (P < 0.05), but not seen in INF-induced protein with tetratricopeptide repeats 1 (IFIT1) and IFN-stimulated gene 15 (ISG15). The expression levels of IFNα, IFNß, IFNαR1, STAT1 and MX1 in lung with EAM model were positively correlated with the scores of lung pathology (all P < 0.05). CONCLUSION: The type I IFN system probably played a crucial role in the pathogenesis and the pathology of muscle and lung of EAM model.

[The safety of hydroxychloroquine in pregnant patients with systemic lupus erythematosus].

OBJECTIVE: To evaluate the efficacy and safety of hydroxychloroquine (HCQ) in pregnant patients with systemic lupus erythematosus (SLE). METHODS: Twenty-four pregnant patients with SLE treated with HCQ during pregnancy from May, 2006 to February, 2011 were studied retrospectively. All babies were followed up during early infancy for growth development. RESULTS: Of them, 22 patients were treated with HCQ throughout the whole pregnancy with no lupus flare occurred in 21 patients (95.4%), while temporary discontinuation of HCQ precipitated a flare of disease in two patients. Three patients (12.5%) had premature delivery, and pregnancy induced hypertension happened in 3 patients (12.5%). No congenital abnormalities occurred and mean follow-up of 26 months (range 1 - 47 months) revealed no abnormalities in these children. CONCLUSION: Our findings reinforce the safety of HCQ therapy during pregancy and HCQ should probably be maintained throughout the pregancy in patients with SLE.

[A study of serum cartilage oligomeric matrix protein and matrix metalloproteinase-3 concentration in osteoarthritic rabbit models].

OBJECTIVE: To study the levels of cartilage oligomeric matrix protein (COMP) and matrix metalloproteinase-3 (MMP-3) in the serum fluid of osteoarthritic rabbit models and their relationships with the severity of pathological changes, so as to investigate their correlation with osteoarthritis (OA). METHODS: The osteoarthritic animal models were get from immobilizing the right knees of 18 rabbits in full extension using plaster cast. Knee joint pathological changes of 2, 6 weeks were examined for pathological severity of OA; ELISA sandwich method was used to measure the levels of COMP and MMP-3 in serum before and after modeling (at 2, 6 weeks respectively); X ray of model keens was also obtained in different period. Correlation analysis was performed to demonstrate the relationship between the levels of COMP, MMP-3 in the serum and the pathological severity of OA. RESULTS: (1) Morphological observations:immobilizing the right knees of rabbits in full extension using plaster cast was a reliable method for osteoarthritic animal models and the typical histopathologic character was seen; the severity of osteoarthritis gradually increased with time extended. (2) The levels of COMP [(3.64 ± 0.18) µg/L], MMP-3 [(1.99 ± 0.81) µg/L] in the serum of 2 weeks osteoarthritic animal models were higher than those before immobilizing with plaster cast [COMP (3.35 ± 0.20) µg/L, MMP-3 (1.61 ± 0.71) µg/L]. The levels of COMP [(3.96 ± 0.44) µg/L], MMP-3 [(3.44 ± 0.91) µg/L] of 6 weeks were much higher, with a significant difference (P < 0.05). The levels of COMP, MMP-3 in serum had a linear correlation with the pathological severity of OA (r > 0.710, and P < 0.05). CONCLUSION: The levels of COMP and MMP-3 in serum can help to predict and evaluate the progression of OA.

[Expression of interferon and its correlation with clinical features in idiopathic inflammatory myopathies].

OBJECTIVE: To detect the expression levels of interferons IFNα, IFNß and IFNγ in the peripheral blood and muscle of patients with idiopathic inflammatory myopathies (IIM) so as to analyze their relationships with organ manifestations. METHODS: The serum levels of IFNα, IFNß, IFNγ and anti-Jo-1antibody were measured with ELISA (enzyme-linked immunosorbent assay). And the method of SYBR green dye based real-time quantitative PCR (polymerase chain reaction) was used to compare the expression levels of IFNα, IFNß, interferon α receptor 1 (IFNαR1), signal transducer and activator of transcription 1 (STAT1) in the IIM patients and normal controls. RESULTS: The serum levels of IFNα (50.2 ± 21.0) ng/L and IFNß (10.7 ± 5.4) ng/L in IIM patients were significantly higher than those in normal controls (18.6 ± 3.6) ng/L, (3.9 ± 0.8) ng/L (P < 0.01). And the serum levels of IFNα (55.7 ± 21.9) ng/L and IFNß (11.3 ± 2.3) ng/L in DM patients were significantly higher than those in PM patients (26.1 ± 8.2) ng/L, (6.2 ± 3.5) ng/L (P < 0.05). The serum levels of IFNα and IFNß correlated with the presence of skin rash (P < 0.05). And their serum concentrations correlated positively with erythrocyte sedimentation rate (r = 0.442, P = 0.000; r = 0.562, P = 0.000) and C-reactive protein (r = 0.348, P = 0.004; r = 0.432, P = 0.005)respectively. The serum levels of IFNα and IFNß decreased significantly after treatment in 12 PM/DM (polymyositis/dermatomyositis) patients (P < 0.01). The mRNA expression levels of IFNα, IFNß, IFNαR1 and STAT1 in PM/DM patients were higher than those in normal controls (P < 0.05). CONCLUSION: The expression levels of IFNα and IFNß in PM/DM patients are significantly higher than those in normal controls. And the increments had correlations with disease activity and severity. STAT1 has been implicated in signal transduction of IFNα and IFNß in the muscles of PM/DM patients.

[Myositis disease activity tool in Chinese patients with polymyositis/dermatomyositis].

OBJECTIVE: To test the reliability, discriminating validity and clinical value of myositis disease activity tool in Chinese patients with polymyositis/dermatomyositis (PM/DM). METHODS: Fifty-four PM/DM patients (PM, n = 18; DM, n = 36) at our hospital between January 2009 and June 2010 were enrolled into this prospective study. The disease activity was assessed by the MDAAT (myositis disease activity assessment tool). The reliability and discriminating validity were assessed with test-retest reliability, interrater reliability and t-test analysis. RESULTS: The reliability analysis of MDAAT indicated 8 items (constitutional, cutaneous, skeletal, gastrointestinal, pulmonary, cardiovascular, muscular & global) had excellent reliability, the ICC (intraclass correlation coefficient) was 0.72 (95%CI: 0.57, 0.83), 0.88 (95%CI: 0.79, 0.93), 0.83 (95%CI: 0.72, 0.90), 0.62 (95%CI: 0.42, 0.76), 0.81 (95%CI: 0.70, 0.89), 0.59 (95%CI: 0.38, 0.74), 0.85 (95%CI: 0.75, 0.91) and 0.84 (95%CI: 0.73, 0.90) respectively. MDAAT had excellent discrimination validity in all items except for cardiovascular ones. CONCLUSION: With excellent reliability and discriminating validity, MDAAT may be used to assess the disease activity and therapeutic effects of Chinese PM/DM patients.

Aberrantly Expressed Galectin-9 Is Involved in the Immunopathogenesis of Anti-MDA5-Positive Dermatomyositis-Associated Interstitial Lung Disease.

BACKGROUND: Dermatomyositis (DM) associated rapidly progressive interstitial lung disease (RP-ILD) has high mortality rate and poor prognosis. Galectin-9 (Gal-9) plays multiple functions in immune regulation. We investigated Gal-9 expression in DM patients and its association with DM-ILD. METHODS: A total of 154 idiopathic inflammatory myopathy patients and 30 healthy controls were enrolled in the study. Cross-sectional and longitudinal studies were used to analyze the association between serum Gal-9 levels and clinical features. Enzyme-linked immunosorbent assay and qRT-PCR were used to examine Gal-9 expression in the sera and isolated peripheral blood mononuclear cells (PBMCs) from DM patients. Immunohistochemistry was performed to analyze the expression of Gal-9 and its ligand (T-cell immunoglobulin mucin (Tim)-3 and CD44) in lung tissues from anti-melanoma differentiation-associated gene 5 (MDA5)-positive patients. The effect of Gal-9 on human lung fibroblasts (MRC-5) was investigated in vitro. RESULTS: Serum Gal-9 levels were significantly higher in DM patients than in immune-mediated necrotizing myopathy patients and healthy controls (all p < 0.001). Higher serum Gal-9 levels were observed in anti-MDA5-positive DM patients than in anti-MDA5-negative DM patients [33.8 (21.9-44.7) vs. 16.2 (10.0-26.9) ng/mL, p < 0.001]. Among the anti-MDA5-positive DM patients, serum Gal-9 levels were associated with RP-ILD severity. Serum Gal-9 levels were significantly correlated with disease activity in anti-MDA5-positive DM patients in both cross-sectional and longitudinal studies. PBMCs isolated from anti-MDA5-positive DM patients (3.7 ± 2.3 ng/mL) produced higher levels of Gal-9 than those from immune-mediated necrotizing myopathy patients (1.1 ± 0.3 ng/mL, p = 0.022) and healthy controls (1.4 ± 1.2 ng/mL, p = 0.045). The mRNA levels of Gal-9 were positively correlated with the levels of type-I interferon-inducible genes MX1 (r = 0.659, p = 0.020) and IFIH1 (r = 0.787, p = 0.002) in PBMCs from anti-MDA5-positive DM patients. Immunohistochemistry revealed increased Gal-9 and Tim-3 expression in the lung tissues of patients with DM and RP-ILD. In vitro stimulation with Gal-9 protein increased CCL2 mRNA expression in MRC-5 fibroblasts. CONCLUSIONS: Among anti-MDA5-positive DM patients, Gal-9 could be a promising biomarker for monitoring disease activity, particularly for RP-ILD severity. Aberrant expression of the Gal-9/Tim-3 axis may be involved in the immunopathogenesis of DM-ILD.