Overview of lupus nephritis management guidelines and perspective from Asia.

Lupus nephritis (LN) is a common and important manifestation of systemic lupus erythematosus (SLE). Evidence suggests higher rates of lupus renal involvement in Asian populations, and maybe more severe nephritis, compared with other racial or ethnic groups. The management of LN has evolved considerably over the past three decades, based on observations from clinical studies that investigated different immunosuppressive agents including corticosteroids, cyclophosphamide, azathioprine, mycophenolic acid, calcineurin inhibitors and novel biologic therapies. This is accompanied by improvements in both the short-term treatment response rate and long-term renal function preservation. Treatment guidelines for LN have recently been issued by rheumatology and nephrology communities in U.S.A. and Europe. In view of the racial difference in disease manifestation and response to therapy, and the substantial disease burden in Asia, a panel of 15 nephrologists and rheumatologists from different Asian regions with extensive experience in lupus nephritis - the Steering Group for the Asian Lupus Nephritis Network (ALNN) - met and discussed the management of lupus nephritis in Asian patients. The group has also reviewed and deliberated on the recently published recommendations from other parts of the world. This manuscript summarizes the discussions by the group and presents consensus views on the clinical management and treatment of adult Asian patients with LN, taking into account both the available evidence and expert opinion in areas where evidence remains to be sought.

Identification of microRNA-31 as a novel regulator contributing to impaired interleukin-2 production in T cells from patients with systemic lupus erythematosus.

OBJECTIVE: MicroRNAs (miRNAs) function to fine-tune the control of immune cell signaling. It is well established that there are abnormalities in the interleukin-2 (IL-2)-related signaling pathways in systemic lupus erythematosus (SLE). The miR-31 microRNA has been found to be markedly underexpressed in patients with SLE, and thus the present study was undertaken to investigate the role of miR-31 in IL-2 defects in lupus T cells. METHODS: Expression levels of miR-31 were quantitated using TaqMan miRNA assays. Transfection and stimulation of cultured cells followed by TaqMan quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and reporter gene assays were conducted to determine the biologic function of miR-31. NF-AT nuclear translocation and expression were quantitatively measured using an ImageStream cytometer. Bioinformatics analysis, small interfering RNA (siRNA) knockdown, and Western blotting were performed to validate miR-31 targets and effects. RESULTS: The expression of miR-31 was significantly decreased in lupus T cells, and this was positively correlated with the expression of IL-2. Overexpression of miR-31 in T cells increased the production of IL-2 by altering NF-AT nuclear expression and IL2 promoter activity, while knockdown of endogenous miR-31 reduced IL-2 production. RhoA expression was directly repressed by miR-31 in T cells. Of note, siRNA-mediated knockdown of RhoA enhanced IL2 promoter activity and, consequently, up-regulated IL-2 production. RhoA expression was consistently up-regulated and negatively correlated with the levels of miR-31 in lupus T cells. Manipulation of miR-31 expression in lupus T cells restored the expression of IL-2 at both the messenger RNA and protein levels. CONCLUSION: MicroRNA-31 is a novel enhancer of IL-2 production during T cell activation. Dysregulation of miR-31 and its target, RhoA, could be a novel molecular mechanism underlying the IL-2 deficiency in patients with SLE.

Sex-specific association of X-linked Toll-like receptor 7 (TLR7) with male systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a multisystem, autoimmune disease that predominantly affects women. Previous findings that duplicated Toll-like receptor 7 (Tlr7) promotes lupus-like disease in male BXSB mice prompted us to evaluate TLR7 in human SLE. By using a candidate gene approach, we identified and replicated association of a TLR7 3'UTR SNP, rs3853839 (G/C), with SLE in 9,274 Eastern Asians (P(combined) = 6.5 x 10(-10)), with a stronger effect in male than female subjects [odds ratio, male vs. female = 2.33 (95% CI = 1.64-3.30) vs. 1.24 (95% CI = 1.14-1.34); P = 4.1 x 10(-4)]. G-allele carriers had increased TLR7 transcripts and more pronounced IFN signature than C-allele carriers; heterozygotes had 2.7-fold higher transcripts of G-allele than C-allele. These data established a functional polymorphism in type I IFN pathway gene TLR7 predisposing to SLE, especially in Chinese and Japanese male subjects.

miR-155 and its star-form partner miR-155* cooperatively regulate type I interferon production by human plasmacytoid dendritic cells.

The recent discovery of microRNAs (miRNAs) has revealed a new layer of gene expression regulation, affecting the immune system. Here, we identify their roles in regulating human plasmacytoid dendritic cell (PDC) activation. miRNA profiling showed the significantly differential expression of 19 miRNAs in PDCs after Toll-like receptor 7 (TLR7) stimulation, among which miR-155* and miR-155 were the most highly induced. Although they were processed from a single precursor and were both induced by TLR7 through the c-Jun N-terminal kinase pathway, miR-155* and miR-155 had opposite effects on the regulation of type I interferon production by PDC. Further study indicated that miR-155* augmented interferon-α/ß expression by suppressing IRAKM, whereas miR-155 inhibited their expression by targeting TAB2. Kinetic analysis of miR-155* and miR-155 induction revealed that miR-155* was mainly induced in the early stage of stimulation, and that miR-155 was mainly induced in the later stage, suggesting their cooperative involvement in PDC activation. Finally, we demonstrated that miR-155* and miR-155 were inversely regulated by autocrine/paracrine type I interferon and TLR7-activated KHSRP at the posttranscriptional level, which led to their different dynamic induction by TLR7. Thus, our study identified and validated novel miRNA-protein networks involved in regulating PDC activation.

MicroRNA-125a contributes to elevated inflammatory chemokine RANTES levels via targeting KLF13 in systemic lupus erythematosus.

OBJECTIVE: MicroRNA (miRNA) have received increasing attention as posttranscriptional regulators that fine-tune the homeostasis of the inflammatory response. This study aimed to clarify whether miR-125a, which was identified in a pilot expression profiling step, is involved in the inflammatory chemokine pathway in systemic lupus erythematosus (SLE). METHODS: Independent verification of miR-125a expression in amplified samples from SLE patients and normal controls was performed by TaqMan quantitative polymerase chain reaction (PCR) analysis. A combination of 3 bioinformatic prediction techniques and reporter gene assays was used to identify miR-125a targets. In vitro systems of overexpression by transfection and inducible expression by stimulation were performed to investigate the function of miR-125a, which was followed by real-time quantitative PCR and enzyme-linked immunosorbent assay. RESULTS: In SLE patients, the expression of miR-125a was reduced and the expression of its predicted target gene, KLF13, was increased. Bioinformatics predicted that miR-125a base-paired with sequences in the 3'-untranslated region of KLF13. Overexpression of miR-125a led to a significant reduction in the expression of RANTES and KLF13. MicroRNA-125a inhibited endogenous KLF13 expression in a dose-dependent manner, as determined using gain- and loss-of-function methods. A luciferase reporter system confirmed the miR-125a binding sites. Notably, miR-125a expression was induced in T cells in a dose- and time-dependent manner. Finally, the introduction of miR-125a into T cells from SLE patients alleviated the elevated RANTES expression. CONCLUSION: MicroRNA-125a negatively regulates RANTES expression by targeting KLF13 in activated T cells. The underexpression of miR-125a contributes to the elevated expression of RANTES in SLE. Our findings extend the role of miRNA in the pathogenesis of lupus and provide potential strategies for therapeutic intervention.

[A multicenter, double-blind, placebo-controlled, randomized, phase III clinical study of etanercept in treatment of ankylosing spondylitis].

OBJECTIVE: To evaluate the short-term efficacy and safety of etanercept treatment in Chinese patients with active ankylosing spondylitis (AS). METHODS: This was a 12-week multicenter, double-blind, placebo-controlled, randomized phase III clinical study. The first part was a 6-week placebo-controlled period followed by a 6-week open-label period. The primary efficacy endpoint was the percentage of subjects achieving a 20% improvement in assessment in ankylosing spondylitis (ASAS) (ASAS 20). The secondary efficacy endpoints were the percentage of patients achieving a 40% improvement in ASAS (ASAS 40), achieving a 50% improvement in ASAS (ASAS 50), achieving a 70% improvement in ASAS (ASAS 70), and ASAS 5/6 responses at all visits, and the improvement in subject global assessment, physician global assessment, nocturnal and total back pain, bath AS functional index (BASFI), bath AS disease activity index (BASDAI), spinal mobility, joint assessment and quality of life assessment. All subjects in the study were evaluated for safety. RESULTS: The primary endpoint, ASAS 20 at week 6, was achieved by 86.5% (64/74) patients in the etanercept group compared to 29.5% (23/78) patients in the placebo group (P < 0.001). As early as week 2, the percentages of patients achieving the ASAS 20 between the two groups were significantly different. Furthermore, the majority of secondary efficacy end points were also significantly improved. Most of adverse events (AE) were mild in nature, the commonest adverse events were elevated liver function levels, injection site reactions and nasopharyngitis. No death or serious AE were observed. CONCLUSION: Etanercept can improve symptoms fastly, significantly and safely in Chinese patients with active AS.

Evaluation of risk factors that contribute to high prevalence of premature atherosclerosis in Chinese premenopausal systemic lupus erythematosus patients.

OBJECTIVE: To evaluate the prevalence of atherosclerosis in Chinese premenopausal women with systemic lupus erythematosus (SLE) and study possible associations between traditional and nontraditional risk factors with premature atherosclerosis. METHODS: We evaluated 111 premenopausal women with SLE and 40 healthy controls without clinical cardiovascular disease. B-mode ultrasound was used to measure carotid plaque and intima-media wall thickness (IMT). The frequency of risk factors for atherosclerosis in patients and controls was compared, and the relationship between the patients' clinical characteristics and carotid plaque was examined. At the same time, we used B-mode ultrasound to measure flow-mediated dilation (FMD) and nitroglycerin-mediated dilation (NMD) in the brachial artery to assess for difference in endothelial function between SLE patients and controls. RESULTS: Carotid plaque was more frequent in patients with lupus (16 of 111 patients) than in control subjects (0 of 40 subjects) (P = 0.007). The mean IMT was significantly higher in patients than in controls. Compared with controls, SLE patients were found to have a significantly higher prevalence of hypertension (P = 0.001), hypercholesterolemia (P = 0.022), and hypertriglyceridemia (P < 0.001). As compared with patients without plaque, patients with plaque were significantly older, had longer disease duration, higher body mass index, raised blood pressure, shorter prothrombin time, raised C-reactive protein, higher Systemic Lupus International Collaborating Clinics damage index score, higher cumulative prednisone dose, used less hydroxychloroquine, had higher mean IMT, lower FMD, and NMD. In logistic regression analysis, older age, higher body mass index, and higher Systemic Lupus International Collaborating Clinics damage index score were independently related to the presence of plaque. Using multiple regression analysis, we found SLE (P = 0.003) to be significantly associated with impaired FMD. CONCLUSION: In our Chinese SLE group, patients presented a higher prevalence of carotid atherosclerosis plaque than healthy controls. SLE patients have significant endothelial dysfunction. We found that risk factors identified in other SLE populations were associated with atherosclerosis in our Chinese group.

Takayasu's arteritis presenting with bilateral pulmonary granulomatosis.

Takayasu's arteritis (TA) is a vasculitis characterized by inflammation and obliteration of intermediate to large-size arteries. We report a case of Takayasu's arteritis with a presentation of bilateral pulmonary nodular infiltrates in a 21-year-old man. An open-lung biopsy showed characteristic changes of extra-vascular granulomatosis. To our knowledge, this has not been described previously in the literature.

Could 2'5'-oligoadenylate synthetase isoforms be biomarkers to differentiate between disease flare and infection in lupus patients? A pilot study.

2'5'-Oligoadenylate synthetase (OAS) was shown to be related to systemic lupus erythematosus (SLE) 20 years ago, and was rediscovered to be involved in type I interferon pathway in SLE by several microarray gene expression studies recently. The goal of this study was to investigate OAS isoform expressions in lupus patients, to evaluate whether they could become biomarkers to differentiate between disease flare and infection. Fifty-four SLE patients presented with fever or systemic inflammatory syndrome, or both, were enrolled. Gene expressions of OAS1, OAS2, and OASL were studied by using real time PCR in active SLE (SLEDAI >or=9, n=29) and in those complicated with infections (n=25). The latter group was composed of 19 patients with invasive bacterial infections, and six patients with viral infections. C reactive protein (CRP) and other clinical parameters were also measured. Twenty-nine healthy individuals made up a normal control group. The mRNA expressions of OAS1, OAS2, and OASL were higher in patients with lupus flares than those with infections (p<0.03), or normal controls (p<0.001). SLE complicated with infections have higher OAS1 expression level (P=0.002), lower OASL (P=0.004), and equivalent OAS2 (P=0.135), when compared with those of normal controls. OASL expression level was negatively correlated with infection in lupus by logistic regression analysis (p=0.008). Area under the receiver operating characteristic curve for the prediction of infection was 0.92 (p<0.0001) for OASL, and 0.77 (p=0.007) for CRP. Therefore, our preliminary data suggest that the pattern of OAS isoform expressions, OASL in particular, may provide useful information in differentiating disease flares from certain infections in SLE.

Clinical features, prognostic and risk factors of central nervous system infections in patients with systemic lupus erythematosus.

The purpose of this study is to describe the etiology, characteristics and outcomes of central nervous system (CNS) infections in patients with systemic lupus erythematosus (SLE), while also identifying prognostic and risk factors. Thirty-eight SLE patients with CNS infections were identified from review of all charts of patients with SLE hospitalized from January 1995 to June 2005. These patients were divided into 3 groups, i.e., Mycobacterium tuberculosis (TB), non-TB bacterial and fungal infection groups. Of the 38 SLE cases with CNS infections, TB was identified in 19 patients, Listeria monocytogenes in 3 patients, Klebsiella pneumoniae in 1 patient, Staphylococcus aureus in 1 patient, Gram's stain positive bacteria in 1 patient, Cryptococcus neoformans in 12 patients, and Aspergillus fumigatus in 1 patient. The rate of unfavorable outcome in patients with fungal infection was lower than in patients with TB (P=0.028) and non-TB bacterial CNS infections (P=0.046). SLE patients with TB or fungal CNS infections had a more insidious or atypical clinical presentation. Compared to SLE patients without CNS infections, those with CNS infections were more likely to have low serum albumin levels (P=0.048) and have been receiving higher doses of prednisolone at the onset of CNS infection (P=0.015) or higher mean doses of prednisolone within the previous year (P=0.039). In conclusion, low levels of serum albumin and higher doses of received prednisolone are important risk factors for the development of CNS infections in SLE patients.

Adult clinically amyopathic dermatomyositis with rapid progressive interstitial lung disease: a retrospective cohort study.

The aim of the study was to investigate the characteristics of adult clinically amyopathic dermatomyositis (CADM) with rapid progressive interstitial lung disease (ILD). Hospitalized patients with dermatomyositis (DM) and polymyositis (PM) between 1998 and 2005 in the Shanghai Renji Hospital were retrospectively studied. One hundred and forty-five patients were classified into CADM, classic DM or PM according to the modified Sontheimer's definition or Bohan-Peter's classification criteria. They were further stratified based on the presence or absence of clinical ILD. The Kaplan-Meier survival analysis and COX regression were performed. The predictive factors for ILD and other clinical properties of CADM-ILD were explored. The presence of clinical ILD was a significant risk factor for the poor outcome of DM/PM (OR = 4.237, CI 95%: 1.239-14.49, p = 0.021). Other risk factors are the presence of rashes and elevated urea nitrogen. Patients with DM/PM complicated by ILD had different clinical courses. Patients with CADM-ILD showed a rapidly progressive pattern with 6-month survival rate of 40.8%. The DM-ILD manifested a progressive pattern with a 5-year survival rate of 54%, while PM-ILD was chronic with 5- and 10-year survival rate of 72.4% and 60.3%, respectively. Better preserved muscle strength, elevated erythrocyte sedimentation rate, and hypoalbuminemia may herald ILD in DM/PM. Patients with CADM-ILD who later died had lower PO(2), higher lactate dehydrogenase, and prominent arthritis/arthralgia compared with those who survived. The presence of antinuclear antibody seems to be protective. Rapid progressive CADM-ILD is refractory to conventional treatment. ILD is a common complication in over 40% of our hospitalized DM/PM cohort and is also a prominent prognostic indicator. CADM is a special phenotype of DM/PM. CADM-ILD, which is usually rapidly progressive and fatal, requires further investigation.

Elevated levels of soluble fractalkine and increased expression of CX3CR1 in neuropsychiatric systemic lupus erythematosus.

The aim of the present study was to determine the levels of soluble fractalkine (sFKN) and expression of CX3CR1 in neuropsychiatric systemic lupus erythematosus (NPSLE). Disease activity of SLE was assessed using the SLE Disease Activity Index (SLEDAI). The mRNA expression levels of CX3CR1 and FKN were quantified using reverse transcription-quantitative polymerase chain reaction. Levels of sFKN in the serum and cerebrospinal fluid (CSF) were measured using enzyme-linked immunosorbent assays. The mRNA expression levels of CX3CR1 in peripheral blood mononuclear cells from patients with NPSLE, non-NPSLE and Behcet's disease were significantly higher than that of rheumatoid arthritis and healthy persons. Levels of sFKN in the serum and CSF of cells with diffuse NPSLE (DNPSLE) were significantly higher than those of focal NPSLE (FNPSLE) cells. Serum levels of sFKN were higher in patients with NPSLE or non-NPSLE than heathy persons. sFKN in CSF were significantly higher in DNPSLE than non-NPSLE cells, but there were no significant difference between FNPSLE and control. Treatment reduced sFKN in serum and CSF in patients with NPSLE. There was significant correlation between sFKN in the serum of patients with SLE and the SLEDAI. sFKN levels were correlated with IgG in CSF from patients with NPSLE. The mRNA expression levels of CX3CR1 in the brain tissue of lupus mice were significantly higher than normal mice; however, the mRNA expression of FKN was lower than normal mice. These results suggest that sFKN and CX3CR1 may be involved in vasculitis and SLE, particularly in DNPSLE, which may occur by damaging the blood-brain barrier or recruiting expression microglial cells of CX3CR1. Additionally, sFKN appears to be a serological marker in patients with SLE, and may be useful for the diagnosis and treatment of NPSLE.

[Peripheral blood mRNA and interferon gene expression in systemic lupus erythematosus].

OBJECTIVE: To investigate the expression levels of interferon (IFN)-alpha, -beta, -omega and -gamma genes and proteins in the peripheral blood of patients with systemic lupus erythematosus (SLE), and to evaluate any possible connections between these expression levels with clinical features. METHODS: 144 SLE patients, 27 non-SLE patients with rheumatisms and 59 normal controls were recruited for the research, and all subjects were drawn blood to isolate plasma and elute total RNA. SYBR Green Dye based real-time quantitative PCR method was used to compare the expression levels of 4 IFNs in patients with SLE and those in the controls. The significance for the correlation of these expression levels and disease activity and specificity was studied. RESULTS: (1) mRNA expression levels of all 4 IFNs in SLE patients were remarkably lower than those observed in normal controls (P < 0.01 in all); IFN-alpha expression levels in SLE patients were increased than those observed in non-SLE group (P < 0.01). (2) The expression levels of all 4 IFNs in active SLE patients were similar to those observed in inactive SLE patients (P > 0.05 in all), and expression levels of all 4 IFNs in patients with SLE were not correlated with involvements of kidney, lung, brain, blood. (3) IFN score in SLE patients was remarkably lower than that observed in normal controls (P < 0.01). (4) The expression levels of all 4 IFNs in both SLE patients and normal controls were positively correlated with each other (P < 0.01 in all). (5) Protein levels of IFN-alpha, IFN-beta and IFN-omega in patients with SLE were similar to those observed in normal group (P > 0.05 in all), protein level of IFN-alpha in active SLE group was apparently elevated than in inactive SLE group (P < 0.01), and protein level of IFN-gamma has a trend to increase in SLE group than in normal group. CONCLUSIONS: Decreased expression levels of IFN-alpha, -beta, -omega and -gamma have implicated significance in the determination of SLE disease specificity, of which IFN-alpha is the best. Lower expression level of IFN score has also significance in the determination of SLE disease specificity. Higher protein level of IFN-alpha is helpful to judging SLE disease activity.

[Variations within OLF1/EBF-associated zinc finger protein gene confer susceptibility to lupus nephritis in Chinese population].

OBJECTIVE: To observe whether single nucleotide polymorphisms (SNPs) within the OLF1/EBF-associated zinc finger protein (OAZ) gene are associated with lupus nephritis (LN) susceptibility in Chinese population. METHODS: Eight SNPs located around the positive microsatellite marker D16S517 within OAZ gene with relatively high heterozygosity were chosen for genotyping on 184 systemic lupus erythromatosus (SLE) patients, including 101 non-LN patients and 83 LN patients, and 286 normal controls using TaqMan MGB allelic discrimination method. Data were collected by SDS 2.0 software. Haplotypes and their frequencies were constructed and estimated, and linkage disequilibrium analysis between pairs of SNPs was evaluated by calculating the D Prime using Helixtree program. Case-control study was performed between the SLE, LN, and non-LN groups and normal control group. RESULTS: (1) The frequency of SNP rs1344531 T allele was 47.0% in the SLE patients, significantly higher than that in the controls [38.1%,; chi(2) = 7.300, P = 0.008, OR (95% CI) = 1.441 (1.105 - 1.878)], which showed that the frequency of SNP rs1344531 T allele is associated with SLE susceptibility. The genotypic distribution of SNP rs1344531(CC/CT/TT) differed significantly between the SLE patients (25.5%/54.9%/19.6%) and normal controls (38.1%/47.6%/14.3%) (chi(2) = 8.394, P = 0.015). The CC genotype frequency of the SLE patients was 25.5%, significantly lower than that of the normal controls [38.1%; chi(2) = 7.976, P = 0.005, OR (95% CI) = 0.557 (0.370 - 0.838)] (2) The SNP rs1344531 T allele frequency of the SLE patients was 53.0%, significantly higher than that of the normal controls [38.1%; chi(2) = 11.769, P = 0.001, OR (95% CI) = 1.832 (1.293 - 2.596)], which showed an associated between SNP rs1344531 T allele frequency and LN susceptibility. The genotypic distribution of SNP rs1344531 (CC/CT/TT) differed significantly between the LN patients (22.9%/48.2%/28.9%) and the normal controls (38.1%/47.6%/14.3%) (chi(2) = 12.065, P = 0.002). The CC genotype frequency of the LN patients was 22.9%, significantly lower than that of the normal controls (38.1%) [chi(2) = 6.578, P = 0.013, OR (95% CI) = 0.481 (0.274 - 0.848)]. The TT genotype frequency of the LN patients was 28.9%, significantly higher than that of the normal controls (14.3%) [chi(2) = 9.423, P = 0.003, OR (95% CI) = 2.431 (1.363 - 4.334)]. No statistical significance was observed between the non-LN patients and normal controls in TT genotype frequency. (3) The frequencies of haplotypes containing rs1344531:rs1420676-rs1344531(C-T) [chi(2) = 11.731, P = 0.001, OR (95% CI) = 1.867 (1.302 - 2.676)], rs3803665-rs1420676-rs1344531(C-C-T) [chi(2) = 8.876, P = 0.004, OR (95% CI) = 1.772 (1.213 - 2.589)], and rs2292155-rs3803665-rs1420676-rs1344531(C-C-C-T) [chi(2) = 9.962, P = 0.002, OR (95% CI) = 1.915 (1.274 - 2.880)] were all significantly higher in the LN patients in comparison with the normal control group (41.0% versus 27.1%; 33.3% versus 21.8%; and 27.0% versus 16.2%); while the frequencies of other haplotypes: rs1344531-rs2080353(C-A) [chi(2) = 8.06, P = 0.005, OR (95% CI) = 0.603 (0.424 - 0.856)], rs1344531-rs2080353-rs933564 (C-A-G) [chi(2) = 7.929, P = 0.006, OR (95% CI) = 0.602 (0.422 - 0.859)] were significantly lower than those of the normal control group (39.5% versus 52.2%, and 36.6% versus 49.2%), which produced additional support for such association. CONCLUSION: SNP rs1344531 and some haplotypes containing SNP rs1344531 within OAZ are significantly associated with LN susceptibility. Genetic variants of the OAZ gene are involved in the pathogenesis of LN.

Expression, localization, and clinical application of the RNA binding domain of U1-70kD in HEp-2 cells.

OBJECTIVE: To develop an improved substrate for indirect immunofluorescent test (IIF) to detect anti-U1-70kD autoantibodies. METHODS: The RNA binding domain of U1-70kD (U1BD) complementary DNA was obtained from human larynx carcinoma cell line HEp-2 by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into the mammalian expression vector pEGFP-C1. The recombinant plasmid pEGFP-U1BD was transfected into HEp-2 cells. Immunoblotting (IBT), confocal fluorescence microscopy, and IIF were used to confirm the expression, localization, and antigenicity of fusion proteins of green fluorescent protein (GFP) in transfected HEp-2 cells, which were then analyzed by IIF using human reference sera and compared with untransfected HEp-2 cells simultaneously. RESULTS: (1) The HEp-U1BD cells thus obtained retained their ability to express U1BD-GFP, which showed the antigenicity of U1BD with a characteristic phenotype in IIF. (2) Fifteen IBT-positive anti-U1-70kD sera presented with characteristic cytoplasmic staining on HEp-U1BD by IIF, but five sera without the 70kD reactive band in IBT were not found in the presence of HEp-U1BD pattern. Ten sera of healthy donors couldn't react with HEp-2 and HEp-U1BD at 1:80 attenuant degrees. (3) No differences in expression, localization, or morphology were observed when HEp-U1BD or HEp-2 interacted with the reference sera that could react with Ro/SSA, La/SSB, centromere, histone, and Scl-70 antigens in routine IIF test. CONCLUSIONS: HEp-U1BD cells kept the immunofluorescent properties of HEp-2 cells in an immunofluorescence anti-nuclear antibody (IFANA) test and could be potentially used as a substrate for routine IFANA detection.

Association of large intergenic noncoding RNA expression with disease activity and organ damage in systemic lupus erythematosus.

INTRODUCTION: Despite growing evidence that large intergenic noncoding RNAs (lincRNAs) can regulate gene expression and widely take part in normal physiological and disease conditions, our knowledge of systemic lupus erythematosus (SLE)-related lincRNAs remains limited. The aim of this study was to detect the levels of four lincRNAs (ENST00000500949: linc0949, ENST00000500597: linc0597, ENST00000501992: linc1992, and ENST00000523995: linc3995) involved in innate immunity in the peripheral blood mononuclear cells (PBMCs) of patients with SLE and correlate these lincRNA levels with disease activity, organ damage, clinical features and medical therapies. METHODS: PBMCs were obtained from 102 patients with SLE, 54 patients with rheumatoid arthritis (RA) and 76 healthy donors. lincRNA expression levels were measured by real-time quantitative polymerase chain reaction. Disease activity was assessed using the Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) scores, and organ damage was evaluated with the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index. RESULTS: linc0949 and linc0597 were significantly decreased in patients with SLE compared with patients with RA and healthy control subjects. linc0949 was correlated with SLEDAI-2K score (r = -0.329, P = 0.0007), as well as with complement component C3 level (r = 0.348, P = 0.0003). The level of linc0949 was also reduced in patients with SLE who had the presence of cumulative organ damage. In addition, decreasing expression of linc0949 was associated with lupus nephritis. linc0949 expression significantly increased after treatment, whereas neither disease activity nor organ damage correlated with linc0597 expression. CONCLUSIONS: Our results provide novel empirical evidence that linc0949 could be a potential biomarker for diagnosis, disease activity and therapeutic response in SLE.

Single nucleotide polymorphisms of deoxyribonuclease I and their expression in Chinese systemic lupus erythematosus patients.

BACKGROUND: Previous studies have suggested that interrupted clearance of nuclear DNA-protein complexes after cell death might initiate and propagate systemic lupus erythematosus (SLE). Deoxyribonuclease I (DNaseI) may be responsible for the removal of DNA from nuclear antigens at sites of high cell turnover, thus preventing the onset of SLE. The purpose of this study was to genotype the single nucleotide polymorphisms (SNPs) of DNase1 and characterize its gene expression and alternatively spliced transcripts in Chinese patients with SLE in order to understand the pathogenic role of DNase1 in human SLE. METHODS: Four SNPs located at the 3' end of the DNase1 gene, as listed on the SNP website, were selected for analysis. Those SNPs with relatively high heterozygosity were chosen for genotyping in 312 Chinese SLE families using the Taqman minor groove binder (MGB) allelic discrimination method. Haplotypes were constructed and linkage disequilibrium tests were performed using GeneHunter. DNase1 mRNA expression was detected using real-time polymerase chain reaction (PCR), and alternatively spliced transcripts were isolated using capillary electrophoresis. Any effects the specific SNP haplotypes had on DNase1 gene expression and the alternatively spliced transcripts were also assessed. RESULTS: rs179982 and rs1053874 had high heterozygosity, about 0.5 in this Chinese cohort, while rs1059857 was also found to be heterozygous. Analysis of the haplotype combining rs179982-rs1030874 (C-G) and rs179982-rs1030874-rs1059857 (C-G-G) revealed a skewed transmission in favor of affected offspring. DNase1 gene expression was higher in SLE patients than in normal controls (P < 0.001), but this was not related to disease activity or SNP haplotype. Capillary electrophoresis revealed that the pattern of alternatively spliced transcripts in patients differed from that of normal controls. Furthermore, different SNP haplotype combinations generated different transcript patterns in SLE patients. CONCLUSIONS: The SNP haplotypes are in linkage disequilibrium in Chinese SLE patients and may induce the disease through a modification of DNase1 mRNA splicing rather than at the level of mRNA expression. There is a relatively unique transcript band in SLE patients independent of special haplotype, which suggests that other unknown factors might be involved in adjusting gene expression.

Transfection, overexpression and clinical application of human 60 kDa Ro/SSA autoantigens in HEp-2 cells.

OBJECTIVE: To develop an improved substrate for indirect immunofluorescence test (IIF) for detecting anti-Ro60/Sjogren's syndrome A (Ro/SSA) autoantibodies. METHODS: 60-kDa Ro/SSA autoantigens (Ro60) cDNAs were obtained from human placental cDNA library using polymerase chain reaction (PCR) and were cloned into the mammalian expression vector-pEGFP-C1. Then, the recombinant plasmids were transfected into HEp-2 cells. We confirmed the overexpression, localization and antigenicity of fusion proteins in transfected cells by means of immunoblotting, confocal fluorescence microscopy and IIF. HEp-2 and HEp-Ro60 were analyzed by IIF using a panel of 10 precipitin-positive anti-Ro human sera simultaneously. RESULTS: Stable expression of Ro60-green fluorescent protein (Ro60-GFP) fusion proteins were maintained ten more generations. Ro60-GFP kept the antigenicity of Ro while demonstrating its own characteristic immunofluorescent pattern in HEp-Ro60 cells. The transfectants dramatically increased the sensitivity of IIF testing (a mean increase of 6.7-fold in endpoint titer). Eight over ten (8/10) positive anti-Ro sera showed characteristic immunofluorescent patterns for HEp-Ro60, including two sera that were anti-nuclear antibodies (ANA) negative for untransfected HEp-2. IIF-ANA in all healthy sera was negative for HEp-Ro60. CONCLUSIONS: As a new substrate for IIF, the Ro60 transfectants can be used to detect anti-Ro antibodies. In addition, transfected HEp-2 cells keep the immunofluorescent properties of HEp-2 cells in IIF-ANA tests and can be employed as a substrate for routine IIF-ANA detection.

Leflunomide, a new disease-modifying drug for treating active rheumatoid arthritis in methotrexate-controlled phase II clinical trial.

OBJECTIVE: To evaluate the efficacy and safety of leflunomide in comparison with methotrexate (MTX) on patients with rheumatoid arthritis (RA) in China. METHODS: Five hundred and sixty-six patients with active rheumatoid arthritis were randomly assigned to receive leflunomide at 20 mg once daily or MTX at 15 mg once weekly in a controlled trial. Five hundred and four patients completed the 12-week treatment and some patients continued the treatment for 24 weeks. RESULTS: Both leflunomide and MTX could improve the symptoms, signs, and joint function, but there were no changes in X-ray observations of patients with rheumatoid arthritis. In the leflunomide group, the overall rates of effectiveness at 12 weeks and 24 weeks were 86.94% and 92.31% respectively; the rates of remarkable improvement were 64.95% and 79.81% respectively. In the MTX group, the overall rates of effectiveness at 12 weeks and 24 weeks were 84.04% and 83.15% respectively; the rates of remarkable improvement were 56.81% and 75.28% respectively. According to intent-to-treat analysis, the ACR 20% response rates at 12 weeks and 24 weeks in the leflunomide group were 62.54% and 67.18% respectively, compared with 60.08% and 61.32% respectively in MTX group. No statistical differences were shown in the efficacy between the two groups (P > 0.05). The adverse events in the leflunomide group were gastrointestinal symptoms, skin rash, alopecia, nervous system symptoms, decreased leukocyte count, and elevation of alanine aminotransferase (ALT). Most of these side effects were mild and transient. The incidence of adverse events in the leflunomide group was 16.84%, significantly lower than that in MTX group (28.17%, P = 0.002). CONCLUSIONS: Leflunomide is effective in the treatment of RA with less adverse events than MTX. Its efficacy is similar to MTX, but the incidence of adverse events and the rate of withdrawal due to adverse events were lower in the leflunomide group than in MTX group.

[Deoxyribonuclease I gene expression in systemic lupus erythematosus patients].

OBJECTIVE: To observe whether deoxyribonuclease I (DNASE1) gene expression and its DNASE1 mRNA expression was detected by real-time polymerase chain reaction and its alternatively spliced transcripts were performed by capillary electrophoresis. An analysis was also made to disclose whether specific single nucleotide polymorphisms (SNPs) haplotype had effects onDNASE1 gene expression and its alternatively spliced transcripts. RESULTS: DNASE1 gene expression was higher in SLE patients than in normal controls (P<0.001), and in patients it was found to be of no relationship with SLE disease activity index score. However, it was increased in female patients. Capillary electrophoresis revealed that the pattern of alternatively spliced transcripts in patients was not the same as that in normal controls. Moreover, it seemed that different SNPs haplotype combination might show different transcript pattern in SLE patients. CONCLUSION: In SLE patients, DNASE1 gene expression is abnormal and there are alternatively spliced transcripts different from those in normal controls. DNASE1 gene is a critical factor in the pathogenesis of SLE.