VidSfM: Robust and Accurate Structure-From-Motion for Monocular Videos.

With the popularization of smartphones, larger collection of videos with high quality is available, which makes the scale of scene reconstruction increase dramatically. However, high-resolution video produces more match outliers, and high frame rate video brings more redundant images. To solve these problems, a tailor-made framework is proposed to realize an accurate and robust structure-from-motion based on monocular videos. The key ideas include two points: one is to use the spatial and temporal continuity of video sequences to improve the accuracy and robustness of reconstruction; the other is to use the redundancy of video sequences to improve the efficiency and scalability of system. Our technical contributions include an adaptive way to identify accurate loop matching pairs, a cluster-based camera registration algorithm, a local rotation averaging scheme to verify the pose estimate and a local images extension strategy to reboot the incremental reconstruction. In addition, our system can integrate data from different video sequences, allowing multiple videos to be simultaneously reconstructed. Extensive experiments on both indoor and outdoor monocular videos demonstrate that our method outperforms the state-of-the-art approaches in robustness, accuracy and scalability.

EZH2 deficiency attenuates Treg differentiation in rheumatoid arthritis.

The chromatin modifier enhancer of zeste homolog 2 (EZH2) methylates lysine 27 of histone H3 (H3K27) and regulates T cell differentiation. However, the potential role of EZH2 in the pathogenesis of rheumatoid arthritis (RA) remains elusive. We analyzed EZH2 expression in PBMC, CD4+ T cells, CD19+ B cell, and CD14+ monocytes from active treatment-naïve RA patients and healthy controls (HC). We also suppressed EZH2 expression using EZH2 inhibitor GSK126 and measured CD4+ T cell differentiation, proliferation and apoptosis. We further examined TGFß-SMAD and RUNX1 signaling pathways in EZH2-suppressed CD4+ T cells. Finally, we explored the regulation mechanism of EZH2 by RA synovial fluid and fibroblast-like synoviocyte (FLS) by neutralizing key proinflammatory cytokines. EZH2 expression is lower in PBMC and CD4+ T cells from RA patients than those from HC. EZH2 inhibition suppressed regulatory T cells (Tregs) differentiation and FOXP3 transcription, and downregulated RUNX1 and upregulated SMAD7 expression in CD4+ T cells. RA synovial fluid and fibroblast-like synoviocytes suppressed EZH2 expression in CD4+ T cells, which was partially neutralized by anti-IL17 antibody. Taken together, EZH2 in CD4+ T cells from RA patients was attenuated, which suppressed FOXP3 transcription through downregulating RUNX1 and upregulating SMAD7 in CD4+ T cells, and ultimately suppressed Tregs differentiation. IL17 in RA synovial fluid might promote downregulation of EZH2 in CD4+ T cells. Defective EZH2 in CD4+ T cells might contribute to Treg deficiency in RA.

Robust and Efficient CPU-Based RGB-D Scene Reconstruction.

3D scene reconstruction is an important topic in computer vision. A complete scene is reconstructed from views acquired along the camera trajectory, each view containing a small part of the scene. Tracking in textureless scenes is well known to be a Gordian knot of camera tracking, and how to obtain accurate 3D models quickly is a major challenge for existing systems. For the application of robotics, we propose a robust CPU-based approach to reconstruct indoor scenes efficiently with a consumer RGB-D camera. The proposed approach bridges feature-based camera tracking and volumetric-based data integration together and has a good reconstruction performance in terms of both robustness and efficiency. The key points in our approach include: (i) a robust and fast camera tracking method combining points and edges, which improves tracking stability in textureless scenes; (ii) an efficient data fusion strategy to select camera views and integrate RGB-D images on multiple scales, which enhances the efficiency of volumetric integration; (iii) a novel RGB-D scene reconstruction system, which can be quickly implemented on a standard CPU. Experimental results demonstrate that our approach reconstructs scenes with higher robustness and efficiency compared to state-of-the-art reconstruction systems.

Comparison of the impact of Tripterygium wilfordii Hook F and Methotrexate treatment on radiological progression in active rheumatoid arthritis: 2-year follow up of a randomized, non-blinded, controlled study.

BACKGROUND: Tripterygium wilfordii Hook F (TwHF) alone or in combination with methotrexate (MTX) has been shown to be more effective than MTX monotherapy in controlling the manifestations in subjects with disease-modifying antirheumatic drug (DMARD)-naïve active rheumatoid arthritis (RA) over a 6-month period. The long-term impact of these therapies on disease activity and radiographic progression in RA has not been examined. METHODS: Patients with DMARD-naïve RA enrolled in the "Comparison of Tripterygium wilfordii Hook F with methotrexate in the Treatment of Active Rheumatoid Arthritis" (TRIFRA) study were randomly allocated into three arms with TwHF or MTX or the two in combination. Clinical indexes and radiographic data at baseline and year 2 was collected and compared using an intent-to-treat (ITT) and a per-protocol (PP) analysis. Two radiologists blinded to the treatment scored the images independently. RESULTS: Of 207 subjects 109 completed the 2-year follow up. The number of subjects withdrawing from the study and the number adhering to the initial regimens were similar among the three groups (p > = 0.05). In the ITT analysis, proportions of patients reaching American College of Rheumatology 50% (ACR50) response criteria were 46.4%, 58.0% and 50.7% in the MTX, TwHF and MTX + TwHF groups (TwHF vs MTX monotherapy, p = 0.004). Similar patterns were found in ACR20, ACR70, Clinical Disease Activity Index good responses, European League Against Rheumatism good response, remission rate and low disease activity rate at year 2. The results of the PP analysis agreed with those in the ITT analysis. The changes in total Sharp scores and joint erosion and joint space narrowing during the 2 years were associated with changes in disease activity measured by the 28-joint count Disease Activity Score and were comparable among the three groups (p > 0.05). Adverse events were similar in the three treatment groups. CONCLUSIONS: During the 2-year therapy period, TwHF monotherapy was not inferior to MTX monotherapy in controlling disease activity and retarding radiological progression in patients with active RA. TRIAL REGISTRATION: This is a follow-up study. Original trial registration: ClinicalTrials.gov , NCT01613079 . Registered on 4 June 2012.

Image-based camera localization: an overview.

Virtual reality, augmented reality, robotics, and autonomous driving, have recently attracted much attention from both academic and industrial communities, in which image-based camera localization is a key task. However, there has not been a complete review on image-based camera localization. It is urgent to map this topic to enable individuals enter the field quickly. In this paper, an overview of image-based camera localization is presented. A new and complete classification of image-based camera localization approaches is provided and the related techniques are introduced. Trends for future development are also discussed. This will be useful not only to researchers, but also to engineers and other individuals interested in this field.

Contribution and underlying mechanisms of CXCR4 overexpression in patients with systemic lupus erythematosus.

Aberrant expression of CXCR4 has been indicated to play a role in the pathogenesis of systemic lupus erythematosus (SLE), but the mechanism of CXCR4 dysregulation in SLE is unclear. This study is aimed to explore the clinical significance and possible mechanisms of abnormal CXCR4 expression on B cells from patients with untreated SLE. Expression of CXCR4 on peripheral B cells was determined by flow cytometry and western blotting. Freshly isolated B cells were cultured with exogenous interleukin 21(IL-21) in the presence or absence of CD40 ligand (CD40L) plus anti-IgM antibody (aIgM), and changes in CXCR4 expression were detected. Involvement of phosphatidylinositol 3 kinase (PI3K)/Akt and Janus kinase/Signal transducer and activator of transcription (JAK/STAT) signaling pathways was assessed by adding blocking agents Ly294002 and AG490. Since CD63 is reported to mediate endosomal recruitment of CXCR4 and BCL6 is capable of silencing CD63 gene transcription, we also measured BCL6 and CD63 gene transcription with real-time PCR. It was shown that CXCR4 expression on B cells was significantly upregulated in SLE patients, especially in those with lupus nephritis, and was positively correlated with SLE Disease Activity Index scores and negatively with the serum complement 3 levels (P<0.05). Downregulation of CXCR4 by IL-21 was intact. In contrast, a similar effect of aIgM plus CD40L in downregulating CXCR4 expression was defective in SLE patients but was restored by co-stimulation with IL-21 in vitro. Both Ly294002 and AG490 promoted downregulation of surface CXCR4 expression on B cells from SLE patients (P=0.078 and P=0.064). Furthermore, B cells from SLE patients exhibited diminished CD63 mRNA and enhanced BCL6 mRNA expression (both P<0.05). To sum up, CXCR4 was overexpressed on SLE B cells, positively correlating with disease activity and kidney involvement. Overactivation of the PI3K/Akt and JAK/STAT pathways as well as defective CD63 synthesis may contribute to CXCR4 dysregulation in SLE.

p53 predominantly regulates IL-6 production and suppresses synovial inflammation in fibroblast-like synoviocytes and adjuvant-induced arthritis.

BACKGROUND: Dominant-negative somatic mutations of p53 has been identified in the synovium of patients with rheumatoid arthritis (RA), in which interleukin (IL)-6 has been established as a pivotal inflammatory cytokine. The aim of this study was to clarify the significance of p53 in the longstanding inflammation in RA by modulating IL-6. METHODS: We established adjuvant-induced arthritis (AIA) in Lewis rats and treated them with p53 activator, and then analyzed the histopathology of the synovium and IL-6 expression. Human fibroblast-like synoviocytes (FLS) were cultured and transfected with p53-siRNA or transduced with adenovirus (Ad)-p53, and then assessed with MTT, TUNEL staining, and luciferase assay. IL-1ß, tumor necrosis factor (TNF)-α and IL-17 were used to stimulate FLS, and subsequent IL-6 expression as well as relevant signal pathways were explored. RESULTS: p53 significantly reduced synovitis as well as the IL-6 level in the AIA rats. It controlled cell cycle arrest and proliferation, but not apoptosis. Proinflammatory cytokines inhibited p53 expression in FLS, while p53 significantly suppressed the production of IL-6. Furthermore, IL-6 expression in p53-deficient FLS was profoundly reduced by NF-kappaB, p38, JNK, and ERK inhibitors. CONCLUSION: Our findings reveal a novel function of p53 in controlling inflammatory responses and suggest that p53 abnormalities in RA could sustain and accelerate synovial inflammation mainly through IL-6. p53 may be a key modulator of IL-6 in the synovium and plays a pivotal role in suppressing inflammation by interaction with the signal pathways in RA-FLS. Interfering with the p53 pathway could therefore be an effective strategy to treat RA.

Effect of 3-hydroxy-3-methylglutaryl-coenzyme a reductase inhibitor on disease activity in patients with rheumatoid arthritis: a meta-analysis.

HMG-CoA reductase inhibitors (also known as statins) are widely used as lipid-lowering agents in patients with rheumatoid arthritis (RA) to reduce their cardiovascular risk. However, whether they have an effect on RA disease activity is controversial. This study aimed to investigate the effect of statins on disease activity in RA patients. A systematic literature review was performed using the MEDLINE, EMBASE, Cochrane Library, ISI WEB of Knowledge, Scopus, and Clinical Trials Register databases. Only prospective randomized controlled trials or controlled clinical trials comparing the efficacy of statins with placebo on adult RA patients were included. The efficacy was measured according to the ACR criteria, EULAR criteria, DAS28, HAQ score, ESR, or CRP. The Jadad score was used for quality assessment. The inverse variance method was used to analyze continuous outcomes. A fixed-effects model was used when there was no significant heterogeneity; otherwise, a random-effects model was used. For stability of results, we performed leave-one-study-out sensitivity analysis by omitting individual studies one at a time from the meta-analysis. Publication bias was assessed using Egger test. A total 13 studies involving 737 patients were included in the meta-analysis; 11 studies were included in the meta-analysis based on DAS28, while the other 2 studies were only included in the meta-analysis based on ESR or CRP. The standardized mean difference (SMD) in DAS28 between the statin group and the placebo group was -0.55 (95% CI [-0.83, -0.26], P = 0.0002), with an I2 value of 68%. Subgroup analysis showed that patients with more active disease tended to benefit more from statin therapy (SMD -0.73, P = 0.01) than patients with moderate or low disease activity (SMD -0.38, P = 0.03). Statin therapy also significantly reduced tender joint counts, swollen joint counts, ESR, and CRP compared with placebo, but the reduction in HAQ score and VAS was not significant (P > 0.05). This meta-analysis suggested that statin therapy might be effective in the reduction of RA disease activity measured by DAS28, TJC, SJC, as well as ESR and CRP.

Comparison of Tripterygium wilfordii Hook F with methotrexate in the treatment of active rheumatoid arthritis (TRIFRA): a randomised, controlled clinical trial.

OBJECTIVES: To compare the efficacy and safety of Tripterygium wilfordii Hook F (TwHF) with methotrexate (MTX) in the treatment of active rheumatoid arthritis (RA). METHODS: Design: a multicentre, open-label, randomised controlled trial. All patients were assessed by trained investigators who were unaware of the therapeutic regimen. INTERVENTION: 207 patients with active RA were randomly allocated (1:1:1) to treatment with MTX 12.5 mg once a week, or TwHF 20 mg three times a day, or the two in combination. At week 12, if reduction of the 28-joint count Disease Activity Score (DAS28) was <30% in the monotherapy groups, the patient was switched to MTX+TwHF. The primary efficacy point was the proportion of patients achieving an American College of Rheumatology (ACR) 50 response at week 24. RESULTS: 174/207 (84.1%) patients completed 24 weeks of the trial. In an intention-to-treat analysis, the proportion of patients reaching the ACR50 response criteria was 46.4% (32/69), 55.1% (38/69) and 76.8% (53/69), respectively, in the MTX, TwHF and MTX+TwHF groups (TwHF vs MTX monotherapy, p=0.014; MTX+TwHF vs MTX monotherapy, p<0.001). Similar statistically significant patterns at week 24 were found for ACR20, ACR70, clinical Disease Activity Index good responses, EULAR good response, remission rate and low disease activity rate. Significant improvement in the Health Assessment Questionnaire and 36-item Short-Form Health Survey questionnaire scores from baseline to week 24 was seen in each treatment arm (p<0.05), though no significant difference was found among the treatment arms (p>0.05). The result of per-protocol analysis agreed with that seen in the intention-to-treat analysis. Seven, three and five women in the TwHF, MTX and combination groups, respectively, developed irregular menstruation (TwHF vs MTX monotherapy, p=0.216). CONCLUSIONS: TwHF monotherapy was not inferior to, and MTX+TwHF was better than, MTX monotherapy in controlling disease activity in patients with active RA. TRIAL REGISTRATION NUMBER: NCT01613079.

Defective PTEN regulation contributes to B cell hyperresponsiveness in systemic lupus erythematosus.

PTEN regulates normal signaling through the B cell receptor (BCR). In systemic lupus erythematosus (SLE), enhanced BCR signaling contributes to increased B cell activity, but the role of PTEN in human SLE has remained unclear. We performed fluorescence-activated cell sorting analysis in B cells from SLE patients and found that all SLE B cell subsets, except for memory B cells, showed decreased expression of PTEN compared with B cells from healthy controls. Moreover, the level of PTEN expression was inversely correlated with disease activity. We then explored the mechanisms governing PTEN regulation in SLE B cells. Notably, in normal but not SLE B cells, interleukin-21 (IL-21) induced PTEN expression and suppressed Akt phosphorylation induced by anti-immunoglobulin M and CD40L stimulation. However, this deficit was not primarily at the signaling or the transcriptional level, because IL-21-induced STAT3 (signal transducer and activator of transcription 3) phosphorylation was intact and IL-21 up-regulated PTEN mRNA in SLE B cells. Therefore, we examined the expression of candidate microRNAs (miRs) that could regulate PTEN: SLE B cells were found to express increased levels of miR-7, miR-21, and miR-22. These miRs down-regulated the expression of PTEN, and IL-21 stimulation increased the expression of miR-7 and miR-22 in both normal and SLE B cells. Indeed, a miR-7 antagomir corrected PTEN-related abnormalities in SLE B cells in a manner dependent on PTEN. Therefore, defective miR-7 regulation of PTEN contributes to B cell hyperresponsiveness in SLE and could be a new target of therapeutic intervention.

Pregnancy-related systemic lupus erythematosus: clinical features, outcome and risk factors of disease flares--a case control study.

OBJECTIVE: To investigate the clinical features, outcome, and risk factors of disease flares in patients with pregnancy-related lupus (PRL). METHODS: Medical charts of 155 consecutive PRL inpatients were systematically reviewed, including demographic data, clinical features, laboratory findings, treatment, complications, and outcome. RESULTS: PRL cases were divided into active (a-PRL) (n = 82, 53.0%) and stable lupus (s-PRL) (n = 73, 47.0%). Compared with nonpregnant active female systemic lupus erythematosus (SLE) patients, a-PRL including new-onset lupus (n-PRL) and flare lupus (f-PRL) (n = 41 respectively), had a higher incidence of renal and hematological involvement but less mucocutaneous and musculoskeletal involvement (p<0.05). The incidence of preeclampsia/eclampsia, fetal loss, and preterm birth were significantly higher in a-PRL than in s-PRL (p<0.05). Despite receiving a more vigorous glucocorticoid treatment, a-PRL mothers had a poorer prognosis (p<0.001). Five (6.1%) of them died and 13 (15.9%) developed severe irreversible organ failure, whereas none of these events was observed in the s-PRL group. Multivariate logistic analysis indicated that a history of lupus flares and serological activity (hypocomplementemia and/or anti-dsDNA positivity) at the time of conception were associated with lupus flares in PRL mothers. CONCLUSIONS: SLE patients with a flare history and serological activity at the time of conception were at an increased risk of disease flares during pregnancy and puerperium. a-PRL patients were more prone to renal and hematological involvement, pregnancy complications, and a poorer prognosis despite more vigorous glucocorticoid treatment.

Survival analysis and risk factors for mortality in connective tissue disease-associated pneumomediastinum.

The aim of this study was to analyze the characteristics of patients with diffuse connective tissue diseases (CTDs) complicated by pneumomediastinum and identify the risk factors associated with increased mortality in these patients. Twenty-eight patients with CTD-associated pneumomediastinum, who were admitted to our hospital from January 1997 to June 2012, were prospectively studied. Their demographic characteristics, time to death, and potential risk factors were assessed. Survival curves were depicted by the Kaplan-Meier method. Univariate and multivariate survival analyses were performed by Cox regression. Of the 28 patients, 21 had dermatomyositis; two, polymyositis; three, systemic lupus erythematosus; one, polyarteritis nodosa; and one, undifferentiated CTD. The mean follow-up period was 1,461 days (54-5,264). The cumulative estimated Kaplan-Meier survival rate was 68 % at 1 week, 50 % at 1 month, and 43 % at 1 year. According to univariate analysis, higher serum albumin level (HR 0.87, 95 % CI 0.78-0.98), "slow air leak" (defined as time to progression of dyspnea [newly acquired respiratory failure, mechanical ventilation required, or decrease in PaO2 >30 mmHg after pneumomediastinum]) >3 days (HR 0.07, 95 % CI 0.02-0.34), and early initiation of immunosuppressive agents (within 1 month of steroid therapy; HR 0.27, 95 % CI 0.09-0.81) were associated with better prognosis. Final regression analysis revealed that slow air leak was associated with a lower mortality risk. We found that slow air leak was independently associated with better prognosis. Furthermore, most patients (86 %) who survived for at least 1 month following the pneumomediastinum event subsequently survived beyond 1 year.

Anti-cyclic citrullinated Peptide antibody is associated with interstitial lung disease in patients with rheumatoid arthritis.

OBJECTIVE: Patients with rheumatoid arthritis (RA) are at risk to develop RA-associated interstitial lung disease (RA-ILD). This retrospective study aimed to investigate the potential association of the positivity of serum anti-cyclic citrullinated peptide antibody (anti-CCP2) and rheumatoid factor (RF) with RA-ILD in RA patients. METHODS: A total of 285 RA patients were recruited at the inpatient service of Peking Union Medical College Hospital in China between 2004 and 2013. Individual patients were evaluated for the evidence of ILD. The concentrations of serum anti-CCP2 and RF in individual patients were measured. The potential risk factors for ILD in RA patients were assessed by univariate and multivariate models. RESULTS: There were 71 RA patients with RA-ILD, accounting for 24.9% in this population. The positive rates of anti-CCP2 and RF in the patients with RA-ILD were significantly higher than that in the patients with RA-only (88.7% vs. 67.3%, p<0.001; 84.5% vs. 70.6%, p = 0.02, respectively). Univariate and multivariate logistic regression analysis revealed that RA patients with positive serum anti-CCP2, but not RF, were associated with an increased risk of ILD (crude odds ratio [cOR] 3.83, 95% confidence interval [CI] 1.74-8.43, p<0.001; adjusted odds ratio [aOR] 3.50, 95% CI 1.52-8.04, p<0.001). CONCLUSION: Our findings suggest that positive serum anti-CCP2, but not RF, may be associated with RA-ILD in RA patients.

[Interstitial lung disease as an initial manifestation of dermatomyositis].

OBJECTIVE: To explore the clinical features and prognosis of dermatomyositis patients with interstitial lung disease (ILD) as an initial manifestation. METHODS: Medical records of 184 dermatomyositis inpatients complicated with ILD, admitted into Peking Union Medical College Hospital from January 1999 to January 2013, were retrospectively analyzed. The clinical features, biochemical parameters, positive rates of autoantibodies, radiology, pulmonary function tests, pathology, treatments and prognosis were compared between two subgroups of ILD-initial and non-ILD-initial dermatomyositis. RESULTS: The incidence of ILD of dermatomyositis inpatients was 17%. The average age was 48 ± 12 years and the gender ratio of male-to-female was 63: 121. Eighty eight (47.8%) dermatomyositis patients had ILD as an initial manifestation, including (n = 42, 22.8%) of ILD concomitant dermatomyositis (within 1 month) and (n = 46, 25.0%) of ILD before dermatomyositis with an average ahead time of (11 ± 3) months. Patients of ILD-initial dermatomyositis had a higher incidence of dyspnea on exertion, cough and lung crackles, but there were lower incidences of heliotrope rash, chest V area rash, shawl sign and joint involvement than non-ILD-initial dermatomyositis (P < 0.05). The positive rate of anti-Jo-1 antibodies of ILD-initial dermatomyositis group was 13.6%. The main performances of ILD-initial dermatomyositis on pulmonary function tests were diffusing and restrictive ventilation impairment. And there was a lower diffusing rate of carbon monoxide than non-ILD-initial dermatomyositis group (P < 0.01). Organic and non-specific interstitial pneumonias were the major clinical pathology types of ILD-initial dermatomyositis. The mortality rate of ILD-initial dermatomyositis patients was 19.3% and there was no significant difference from non-ILD-initial dermatomyositis (P > 0.05). The main course of ILD-initial dermatomyositis was respiratory failure due to progressive ILD (n = 13, 76.5%). CONCLUSIONS: ILD as an initial manifestation is a common complication and a major mortality cause of dermatomyositis inpatients. And the frequent clinical pathology types are organic and non-specific interstitial pneumonias. Symptoms of skin and muscle, creatine kinase and anti-synthetase antibodies should be closely monitored.

Gene expression profiles of peripheral blood mononuclear cells in primary biliary cirrhosis.

Previous studies on gene expression profiles in primary biliary cirrhosis (PBC) have exclusively focused on liver tissue or intrahepatic cells. Since the pathological process is systemic, other complementary studies in blood cells seemed to be reasonable. In this research, we try to explore differentially expressed genes in peripheral blood mononuclear cells (PBMCs) of PBC patients. Nine PBC patients and 9 healthy controls were recruited as Cohort 1 for a microarray study of screening. Total RNA of PBMCs from each individual was isolated and screened by oligonucleotide microarray (22 K). Then, differentially expressed genes were categorized into signaling pathways. Expression levels of three important genes, tyrosine kinase binding protein (TYROBP), C­C motif chemokine 5 (CCL5) and cathepsin L (CTSL) were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) in a second Cohort 2 (30 PBC patients and 20 healthy controls). Results show that sixty-five genes differentially expressed in PBC were identified, 20 of which were up-regulated and 45 of which were down-regulated. Twenty-seven signaling pathways were identified. TYROBP and CCL5 were proved to be down-regulated in PBC, and CTSL was proved to be up-regulated (p < 0.05) in PBC, which were all consistent with the screening study. In conclusions, the analysis of gene expression in PBMCs of PBC and the comparison of gene profiles between PBMCs and the liver may provide new clues to the pathogenesis of the disease.

Abnormal expression of CD43 in patients with systemic lupus erythematosus and its clinical significance.

BACKGROUND: Previous studies indicate that CD43 plays a role in regulating the adhesion of lymphocytes, cell mutation and activation, however, little is known about its effect on systemic lupus erythematosus (SLE). This study was designed to explore the clinical significance of CD43 in SLE patients. METHODS: We used microarray and real-time PCR to detect the mRNA and protein expression of magnetic bead sorted T cells and B cells from peripheral blood mononuclear cells (PBMCs) of SLE patients, and analyzed the relationship between CD43 and the clinical indexes. RESULTS: Both microarray and real-time PCR results showed that CD43 mRNA was significantly decreased in PBMCs of SLE patients compared with healthy controls (P < 0.001). There were no significant differences between lupus nephritis and non-lupus nephritis patients, and neuropsychiatric and non-neuropsychiatric patients. CD43 mRNA expression was significantly reduced in T cells but not in B-cells in SLE patients compared to healthy controls (P < 0.01). Compared with healthy controls, the percentage of CD43(+) cells in the PBMCs of SLE was significantly decreased (P = 0.004), and the CD43 fluorescence intensity in CD3(+)/CD43(+) cells and CD19(+)/CD43(+) cells was also significantly weaker than in healthy controls (P = 0.039 and 0.003). There was no significant difference in the percentage of CD3(+)/CD43(+) cells, CD19(+)/CD43(+) cells between the two groups. The CD43 fluorescence intensity in CD3(+)/CD43(+) cells was inversely correlated with the levels of IgG and IgM (r = -0.8 and -0.6). CONCLUSIONS: Compared to healthy controls, both CD43 mRNA and protein expressions were reduced in T cells from patients with SLE, and were inversely correlated with IgG.

Aberrant CD200/CD200R1 expression and function in systemic lupus erythematosus contributes to abnormal T-cell responsiveness and dendritic cell activity.

INTRODUCTION: CD200 is a type I transmembrane glycoprotein that can regulate the activation threshold of inflammatory immune responses, polarize cytokine production, and maintain immune homeostasis. We therefore evaluated the functional status of CD200/CD200 receptor 1 (CD200R1) interactions in subjects with systemic lupus erythematosus (SLE). METHODS: Serum CD200 level was detected by ELISA. The expression of CD200/CD200R1 by CD4+ T cells and dendritic cells (DCs) was examined by flow cytometry, and then compared between SLE patients and healthy controls. Peripheral blood mononuclear cells were stained with carboxyfluorescein diacetate succinimidyl ester and annexin V/propidium iodide for evaluation of the effect of CD200 on cell proliferation and apoptosis. In addition, the effect of CD200 on DC function was determined by transwell migration assay as well as by measurement of binding and phagocytosis of apoptotic cells. RESULTS: In SLE patients, the number of CD200+ cells and the level of soluble CD200 were significantly higher than in healthy controls, whereas the expression of CD200R1 by CD4+ T cells and DCs was decreased. Furthermore, the increased CD200 expression by early apoptotic cells contributed to their diminished binding and phagocytosis by DCs in SLE. Importantly, the engagement of CD200 receptor on CD4+ T cells with CD200-Fc fusion protein in vitro reduced the differentiation of T-helper type 17 cells and reversed the defective induction of CD4+CD25highFoxP3+ T cells by transforming growth factor beta in SLE patients. Conversely, blockade of CD200-CD200R1 interaction with anti-CD200R1 antibody promoted CD4+ T-cell proliferation. CONCLUSION: CD200 and CD200R1 expression and function are abnormal in SLE and may contribute to the immunologic abnormalities in SLE.

Low-dose rituximab therapy for refractory thrombocytopenia in patients with systemic lupus erythematosus--a prospective pilot study.

OBJECTIVES: To evaluate the safety and efficacy of low-dose rituximab therapy for refractory thrombocytopenia in patients with SLE. METHODS: Ten adult SLE patients with severe refractory thrombocytopenia (mean platelet count 10.4 × 10(9)/l) were enrolled in this prospective pilot study. All patients had failed traditional high-dose CSs and immunosuppressants including methylprednisolone pulse therapy. Patients were scheduled to receive i.v. rituximab at a dose of 100 mg once weekly for 4 weeks. Previous dose of CSs were gradually tapered, and immunosuppressants were withdrawn. Patients were followed at Weeks 4, 12, 24 and 36. RESULTS: All patients completed four courses of low-dose rituximab infusion. At Week 4, two (20%) patients achieved complete responses (CRs, platelet count >100 × 10(9)/l). The CR rate increased to 60% (six patients) at Week 12, was maintained at Week 24 and began to drop at Week 36 (four patients, 40%). Overall response (OR, platelet count >50 × 10(9)/l) was achieved in 5/10, 6/10, 7/10 and 5/10 patients at Weeks 4, 12, 24 and 36, respectively. Peripheral CD19(+) B cells were depleted (<5 × 10(6)/l) in all patients at Week 4, and gradually increased at Weeks 24 and 36. Serum C3, IgG, IgA and IgM levels did not change significantly (P < 0.05). Infusion reaction was observed in two patients. One patient developed pulmonary thrombosis at Week 14 and active tuberculosis at Week 25. CONCLUSIONS: Low-dose rituximab therapy is effective in treating severe thrombocytopenia in SLE patients who do not respond to vigorous glucocorticoid plus immunosuppressants, and in most cases is safe.

p53 in fibroblast-like synoviocytes can regulate T helper cell functions in patients with active rheumatoid arthritis.

BACKGROUND: p53 is a tumor suppressor and plays a key role in regulating cell hyperplasia, repairing DNA and inducing apoptosis. This study was to investigate p53 expression in fibroblast-like synoviocytes (FLS) and its effect on CD4(+) T lymphocytes from patients with active rheumatoid arthritis (RA). METHODS: Human FLS were transfected with p53 siRNA and cocultured with CD4(+) T lymphocytes from patients with active RA. The expressions of osteoprotegerin and interleukin (IL)-6 were detected in p53 siRNA and scramble siRNA-transfected FLS. In addition, protein levels of interferon (IFN)-γ, IL-17, IL-4 and CD25 as well as mRNAs of IFN-γ, retinoic acid-related orphan receptor (ROR)-γt, IL-17 and Foxp3 in cocultured CD4(+) T lymphocytes were also measured. RESULTS: IL-6 decreased in p53-knockdown FLS while osteoprotegerin expression was not altered. FLS with p53 deletion significantly increased the production of IL-17 and IFN-γ by CD4(+) T cells and upregulated Foxp3 mRNA expression without effects on the proportion of CD4(+)CD25(high) T lymphocytes. CONCLUSION: p53 in FLS might regulate Th1 and Th17 functions in patients with RA and participate in the pathogenesis of RA.