Objective Ankylosing spondylitis (AS) is a rheumatic disease characterized by chronic inflammation and bony ankylosis. This study was to evaluate whether a signal transducer and activator of transcription 3 phosphorylation inhibitor (stat3-p Inh) could treat both chronic inflammation and bone formation in AS. Methods Primary AS osteoprogenitor cells and spinal entheseal cells were examined for osteogenic differentiation. Synovial fluid mononuclear cells (SFMCs) and lamina propria mononuclear cells (LPMCs) were obtained from AS patients. Inflammatory cytokine-producing cells were analyzed using flow cytometry and ELISA. Female SKG mice were treated with stat3-p Inh, IL-17A blocker, or vehicle. Inflammation and new bone formation were evaluated using immunohistochemistry, positron emission tomography and micro–computed tomography (CT). Results In the SKG mouse model, stat3-p Inh significantly suppressed arthritis, enthesitis, spondylitis and ileitis. In experiments culturing SFMCs and LPMCs, the frequencies of IFN-γ, IL-17A, and TNF-α producing cells were significantly decreased after stat3-p Inh treatment. When comparing current treatments for AS, stat3-p Inh showed a comparable suppression effect on osteogenesis to JAK inhibitor or IL-17A blocker in AS-osteoprogenitor cells. Stat3-p Inh suppressed differentiation and mineralization of AS-osteoprogenitor cells and entheseal cells toward osteoblasts. Micro-CT analysis of hind paws revealed less new bone formation in stat3-p Inh-treated mice than vehicle-treated mice (p = 0.005). Hind paw and spinal new bone formation were similar between stat3-p Inh- and anti-IL-17A-treated SKG mice (p = 0.874 and p = 0.117, respectively). Conclusion Stat-3p inhibition is a promising treatment for both inflammation and new bone formation in AS.

Objective: Serum microRNA (miR) in ankylosing spondylitis (AS) patients has been rarely identified. The objective of this study was to find AS-specific miR in sera of patients with AS.Methods: Total RNAs were isolated from whole sera of patients with AS, patients with rheumatoid arthritis (RA), and healthy controls (HC) using miRNeasy Serum/ Plasma Kit. The presence of miR was assayed using Agilent 2100 Bioanalyzer Small RNA assay. Each RNA sample was used for miR microarray. To verify microarray results, candidate circulating miRs were validated by quantitative polymerase chain reaction (qPCR) using samples from patients with AS (n = 65), patients with RA (n = 25), and HCs (n = 39). Cycle threshold values were converted to copy numbers by drawing a standard curve using a synthetic chemical standard. All clinical values were also evaluated at the time of miR isolation. Results:A total of 887 miRs were screened for three groups. Lower expression of miR-214 in AS than in HC and RA was observed after normalization of raw data.Finally, lower expression of serum miR-214 was confirmed in AS after validation by qPCR. Correlation analysis showed that the level of miR-214 of AS was significantly associated with Ankylosing Spondylitis Disease Activity Score-C-reactive protein (r = 0.299, P = 0.02). However, other disease-specific variables showed no statistical significance: gender (P = 0.286), peripheral arthritis (P = 0.634), enthesitis (P = 0.464), dacylitis (P = 0.750), psoriasis (P = 0.552), inflammatory bowel disease (P = 0.369), human leukocyte antigen-B27 positivity (P = 0.473), use of non-steroidal anti-inflammatory drugs (P = 0.448), and use of tumor necrosis factor-blocker in the last 3 months (P = 0.505).Conclusion: miR-214 may serve as a noninvasive biomarker for diagnosis of AS. In addition, expression level of miR-214 was associated with disease activity. K E Y W O R D S ankylosing spondylitis, biomarker, microRNA | 1197 KOOK et al.

Helminth infections and their components have been shown to have the potential to modulate and attenuate immune responses. The objective of this study was to evaluate the potential protective effects of Clonorchis sinensis-derived protein (CSp) on ankylosing spondylitis (AS). Cytotoxicity of CSp at different doses was assessed by MTS and flow cytometry before performing experiments. Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were obtained from AS patients. Inflammatory cytokine-producing cells were analyzed using flow cytometry. The levels of INF-γ, IL-17A, TNF-α, and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA). SKG mice were treated with CSp or vehicles. Inflammation and new bone formation were evaluated using immunohistochemistry, positron emission tomography (PET), and micro-computed tomography (CT). Treatment with CSp resulted in no reduced cell viability of PBMCs or SFMCs until 24 h. In experiments culturing PBMCs and SFMCs, the frequencies of IFN-γ and IL-17A producing cells were significantly reduced after CSp treatment. In the SKG mouse model, CSp treatment significantly suppressed arthritis, enthesitis, and enteritis. Micro-CT analysis of hind paw revealed reduced new bone formation in CSp-treated mice than in vehicle-treated mice. We provide the first evidence demonstrating that CSp can ameliorate clinical signs and cytokine derangements in AS. In addition, such CSp treatment could reduce the new bone formation of AS.

Objectives: This study aims to investigate radiographic progression according to the presence or absence of uveitis in patients with ankylosing spondylitis (AS). Patients and methods: A total of 598 patients (529 males, 69 females, mean age 38.1±9.2 years; range, 18 to 73 years) from the Observation Study of Korean Spondyloarthropathy Registry who met the modified New York criteria for AS were included in this study. At baseline, all data were stratified into two groups according to the presence or absence of uveitis. Baseline and radiographic progression were assessed for five years in this registry. Modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) was read by two radiologists. Reliability was assessed using inter-and intra-class correlation coefficient for each radiograph. Comparison of mSASSS changes was analyzed by analysis of covariance model after adjusting for confounding factors. Results: The evaluation of mSASSS showed good agreement between the two readers. A total of 193 patients (32.27%) had a history of uveitis that presented at a mean age of 39.6 years, including 30 females (15.54%). There were statistically significant differences in age (p=0.01), sex (p=0.04), hip joint involvement (p<0.01), and human leukocyte antigen B27 carrier state (p=0.02) between the two groups according to uveitis. A simple comparison revealed no significant difference in mSASSS change for five years between the two groups (mean: 3.05±0.62 vs. 3.78±0.78, p=0.47). After adjusting for confounding factors in multiple comparisons by Bonferroni correction, patients with uveitis had no significant association with mSASSS change for five years (mean: 6.29±1.32 vs. 5.49±1.39, p=0.68). Conclusion: Our study confirms that there is no significant association between uveitis and radiographic progression in patients with AS after adjusting for confounding factors.

Background: Helminth infections and their components have been shown to have potential to modulate immunity and attenuate immune response. The objective of this study was to evaluate potential protective effects of Clonorchis sinensis–derived protein (CSp) on ankylosing spondylitis (AS).Methods: Cytotoxicity of CSp at different doses was assessed by MTS and flow cytometry before performing experiments. Peripheral blood mononuclear cells (PBMCs) and Synovial fluid mononuclear cells (SFMCs) were obtained from AS patients. Inflammatory cytokine-producing cells were analyzed using flow cytometry. SKG mice were treated with CSp or vehicle. Inflammation and new bone formation were evaluated using immunohistochemistry, positron emission tomography (PET) and micro–computed tomography (CT).Results: Treatment with CSp resulted in no reduced cell viability of PBMCs or SFMCs. In experiments culturing PBMCs and SFMCs, the frequencies of IFN-g and IL-17A producing cells were significantly reduced after CSp treatment. In the SKG mouse model, CSp treatment significantly suppressed arthritis and enthesitis. Micro-CT analysis of hind paw revealed less new bone formation in CSp-treated mice than in vehicle-treated mice. Conclusions: We provide the first evidence demonstrating that CSp can ameliorate clinical signs and cytokine derrangements in AS. In addition, such CSp treatment could reduce new bone formation of AS.