In our study, we observed no difference in the TNF levels of patients and healthy control subjects, and a lack of association with SLEDAI-2K score. 95%CI=0.021-0.150) as independent factors for increased SLEDAI-2K. IL-6, IL-10, and IL-17A are candidate biomarkers for disease activity in cSLE patients. This is the first longitudinal study to support their pivotal role in the pathogenesis of the disease. as substrate and were considered positive if they were higher than 1:10. The C3 and C4 serum levels were determined by nephelometry. Disease activity was assessed by the SLEDAI-2K score in the past 10 days, and scores 4 were considered to be active disease (19). We also measured cumulative damage in our patients by the Systemic Lupus International Collaborating Clinics (SLICC)/ACR Damage Index (SDI). Damage was considered present if scores were 1 (20). Cytokine assay Blood samples were collected, plasma was separated by density gradient centrifugation using the Ficoll-Paque? reagent (GE Healthcare, USA), and aliquots were stored at ?80C until analysis. Levels of IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-, Arglabin and TNF cytokines were determined Arglabin using the Cytometric Bead Array Human Th1/Th2/Th17 Cytokine Kit (BD Biosciences, USA). Quantification was performed using the BD Accuri? C6 flow cytometer (BD Biosciences) and the results were analyzed using FCAPArray? software (BD Biosciences). The experiment was performed according to the manufacturer’s protocol and the results are reported in pg/mL. The detection limits for IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-, and TNF were 2.6, 4.9, 2.4, 18.9, 3.8, 3.7, and 4.5 pg/mL, respectively. Statistical analysis Statistical analyses were performed using SPSS Statistics software version 20 (USA). Continuous variables are reported as meanSD or median and range, and categorical variables are reported as absolute values and percentages. Arglabin The differences in cytokine levels between the studied groups were examined by the Kruskal-Wallis nonparametric test followed by the Mann-Whitney U-test. The Wilcoxon test was used to assess the differences in cytokines between the patients in the longitudinal follow-up study. Spearman rank correlation was used to correlate cytokine levels Rabbit Polyclonal to Bax (phospho-Thr167) (independent variable) with SLEDAI-2K score. Then, only independent variables with P 0.20 were considered for multivariate analysis. Multivariate analysis was performed using a linear regression model (backward stepwise) to understand the association between all the cytokines and the logarithm of the SLEDAI-2K variable. P 0.05 was considered to be statistically significant. Results Demographic, clinical, laboratory, and treatment data The studied groups (cSLE patients and healthy control subjects) were homogeneous for gender and age. Of the 51 cSLE patients, 47 (92%) were female and the median age was 15 years (range 5C20). The median disease duration was 3 years (range 1C9). The median time between the first and second blood collection in the longitudinal study was 11 months (range 9C13). Of the 47 healthy control subjects, 43 (91%) were female and the median age was Arglabin 15 years (range 6C21). At blood collection, 26 patients presented with active disease (SLEDAI-2K 4), and a median score of 6 (range 4C27), and 25 patients presented with inactive disease, and a median score of 2 (range 0C2). Active nephritis (21%), mucocutaneous disorders (16%), and arthritis (12%) were the most common clinical manifestations. All patients were using hydroxychloroquine on the day of blood collection, and 31 (61%) were using prednisone, 25 (49%) were using mycophenolate mofetil, 17 (33%) were using azathioprine, and only 4 (8%) were using methotrexate (Table 1). When indicated, intravenous high dose methylprednisolone was administered after blood collection. Open in a separate window Cytokine secretion profile Plasma levels Arglabin of the Th1, Th2, Th17,.