Inorganic pyrophosphate is reduced in patients with systemic sclerosis.

OBJECTIVE: The pathogenesis of calcinosis cutis, a disabling complication of SSc, is poorly understood and effective treatments are lacking. Inorganic pyrophosphate (PPi) is a key regulator of ectopic mineralization, and its deficiency has been implicated in ectopic mineralization disorders. We therefore sought to test the hypothesis that SSc may be associated with reduced circulating PPi, which might play a pathogenic role in calcinosis cutis. METHODS: Subjects with SSc and age-matched controls without SSc were recruited from the outpatient rheumatology clinics at Rutgers and Northwestern Universities (US cohort), and from the Universities of Szeged and Debrecen (Hungarian cohort). Calcinosis cutis was confirmed by direct palpation, by imaging or both. Plasma PPi levels were determined in platelet-free plasma using ATP sulfurylase to convert PPi into ATP in the presence of excess adenosine 5' phosphosulfate. RESULTS: Eighty-one patients with SSc (40 diffuse cutaneous, and 41 limited cutaneous SSc) in the US cohort and 45 patients with SSc (19 diffuse cutaneous and 26 limited cutaneous SSc) in the Hungarian cohort were enrolled. Calcinosis was frequently detected (40% of US and 46% of the Hungarian cohort). Plasma PPi levels were significantly reduced in both SSc cohorts with and without calcinosis (US: P = 0.003; Hungarian: P < 0.001). CONCLUSIONS: Circulating PPi are significantly reduced in SSc patients with or without calcinosis. Reduced PPi may be important in the pathophysiology of calcinosis and contribute to tissue damage with chronic SSc. Administering PPi may be a therapeutic strategy and larger clinical studies are planned to confirm our findings.

Evaluation of cardiopulmonary exercise test in the prediction of disease progression in systemic sclerosis.

OBJECTIVES: Cardiopulmonary exercise test (CPET) is a widely used examination to predict the prognosis of many chronic pulmonary diseases, and it has also been tested in systemic sclerosis (SSc) with a focus on the development of pulmonary hypertension. CPET is a highly informative non-invasive tool that provides a more complex information than conventional lung function tests to predict the course of cardiopulmonary diseases, as it provides a general overview of the aerobic metabolism, influenced by pulmonary, cardiovascular and peripheral muscle function. The purpose of this investigation was to assess if the progression and the development of poor overall disease outcome in SSc can be predicted by this method. METHODS: Twenty-nine SSc patients were investigated prospectively with standard follow-up plus CPET for a mean of 3.7 years to match the results of conventional evaluation modalities and CPET. A composite end-point of several serious outcomes reflecting SSc-related vascular and cardiopulmonary damage was set up, and the predictive value of and correlations between the CPET parameters and resting lung function and echocardiography variables were assessed. RESULTS: None of the clinical parameters, resting lung function or echocardiographic test results proved to be predictive of the development of the endpoint of poor prognosis in this cohort. In contrast, several CPET parameters were found to discriminate between SSc patients with or without adverse outcome. The detection of desaturation (at any CPET test) was associated with a higher risk of poor prognosis (OR:5.265). VO2 and VE/VCO2 at baseline correlated with the annual decrease in FVC, anaerobic threshold with the development of digital ulcers, and VE/VO2 with the increase in pulmonary arterial pressure. CONCLUSIONS: Several CPET parameters obtained at the beginning of follow-up are informative of the appearance of various adverse end-points. CPET is a feasible examination in the care of SSc patients and provides excess information to current standard follow-up examinations.

Altered Cell Surface N-Glycosylation of Resting and Activated T Cells in Systemic Lupus Erythematosus.

Altered cell surface glycosylation in congenital and acquired diseases has been shown to affect cell differentiation and cellular responses to external signals. Hence, it may have an important role in immune regulation; however, T cell surface glycosylation has not been studied in systemic lupus erythematosus (SLE), a prototype of autoimmune diseases. Analysis of the glycosylation of T cells from patients suffering from SLE was performed by lectin-binding assay, flow cytometry, and quantitative real-time PCR. The results showed that resting SLE T cells presented an activated-like phenotype in terms of their glycosylation pattern. Additionally, activated SLE T cells bound significantly less galectin-1 (Gal-1), an important immunoregulatory lectin, while other lectins bound similarly to the controls. Differential lectin binding, specifically Gal-1, to SLE T cells was explained by the increased gene expression ratio of sialyltransferases and neuraminidase 1 (NEU1), particularly by elevated ST6 beta-galactosamide alpha-2,6-sialyltranferase 1 (ST6GAL1)/NEU1 and ST3 beta-galactoside alpha-2,3-sialyltransferase 6 (ST3GAL6)/NEU1 ratios. These findings indicated an increased terminal sialylation. Indeed, neuraminidase treatment of cells resulted in the increase of Gal-1 binding. Altered T cell surface glycosylation may predispose the cells to resistance to the immunoregulatory effects of Gal-1, and may thus contribute to the pathomechanism of SLE.

An observation on the severity of periodontal disease in past cigarette smokers suffering from rheumatoid arthritis- evidence for a long-term effect of cigarette smoke exposure?

BACKGROUND: Rheumatoid arthritis (RA) and cigarette smoking are both risk factors for periodontal disease (PD). Previous research suggests that systemic inflammatory conditions and cigarette smoking may act in synergy, and their co-occurrence leads to a much higher risk of developing severe stage PD than what the combination of their individual risks would suggest. We originally sought to test this in the case of RA, but it turned out that the majority of our patients were former smokers, who smoked for prolonged periods in the past. For that reason, we decided to shift our focus toward the possible effects of past chronic cigarette smoke exposure. METHODS: The data of 73 RA patients and 77 healthy controls were analyzed. The participants received a full-mouth periodontal examination to determine their periodontal status. Rheumatological indices and data on past tobacco use were also recorded. Both the patient and the control groups were divided into former smoker and non-smoker subgroups for the analyses. Non-smoker controls were used as the reference group. RESULTS: In the control group, smoking in history increased the odds of developing both the moderate and the severe stages of PD, but the change was not statistically significant. RA significantly, increased the odds of developing both stages in itself, but the highest odds were seen in the former smoker RA group. CONCLUSION: Based on this surprising observation of ours, we hypothesize that chronic cigarette smoke might bring about permanent changes in the periodontal tissues, leading to their hypersensitivity to inflammatory challenges.

Dry eye and corneal langerhans cells in systemic lupus erythematosus.

Purpose. Investigation of dry eye and corneal Langerhans cells (LCs) in systemic lupus erythematosus (SLE). Methods. Prospective consecutive case series of 27 SLE patients and 27 control subjects. Dry eye was evaluated by lid-parallel conjunctival folds (LIPCOF), Schirmer test, tear break-up time (TBUT), and ocular surface disease index (OSDI) questionnaire. In vivo investigation of corneal LCs density and morphology (LCM) was performed with confocal corneal microscopy (Heidelberg Retina Tomograph with Rostock Cornea Module). Results. Tear production and stability were pathological in SLE subjects compared to control (Schirmer: 8.45 ± 9.82 mm/5 min versus 11.67 ± 3.21 mm/5 min; TBUT: 6.86 ± 3.53 s versus 11.09 ± 3.37 s). OSDI was significantly greater in SLE patients (25.95 ± 17.92) than in controls (11.06 ± 7.18). Central LC density was greater in SLE patients (43.08 ± 48.67 cell/mm(2)) than in controls (20.57 ± 21.04 cell/mm(2)). There was no difference in the peripheral LC density (124.78 ± 165.39 versus 78.00 ± 39.51 cell/mm(2)). LCM was higher in SLE patients in the centre (1.43 ± 0.79) and in the periphery (2.89 ± 0.42) compared to controls (centre: 1.00 ± 0.69, periphery: 2.35 ± 0.54). Conclusions. Significant changes in dry eye parameters and marked increase of central LCs could be demonstrated in SLE patients. SLE alters not only the LC density but also the morphology, modifies corneal homeostasis, and might contribute to the development of dry eye.

Plasma soluble urokinase plasminogen activator receptor (suPAR) levels in systemic lupus erythematosus.

OBJECTIVE: Soluble urokinase plasminogen activator receptor (suPAR) is a biomarker of systemic inflammation. We aimed to characterize plasma suPAR levels in SLE patients. METHODS: We measured plasma suPAR, C reactive protein (CRP) and erythrocyte sedimentation rate (ESR) in 89 SLE patients and 29 healthy controls. RESULTS: suPAR and ESR values were higher in SLE than in controls, while CRP levels were comparable. ROC analysis of suPAR levels indicated a cut-off value of 5.70 ng/mL to distinguish patients with high disease activity (SLEDAI >8). CONCLUSION: suPAR might be an objective marker for identifying SLE patients with active disease.