Myeloid-derived suppressor cell-derived osteoclasts with bone resorption capacity in the joints of arthritic SKG mice

Background

Myeloid-derived suppressor cells (MDSCs) are heterogeneous immature myeloid cells with immunosuppressive functions. It is known that MDSCs are expanded at inflammatory sites after migrating from bone marrow (BM) or spleen (Sp). In chronic inflammatory diseases such as rheumatoid arthritis (RA), previous reports indicate that MDSCs are increased in BM and Sp, but detailed analysis of MDSCs in inflamed joints is very limited.

Objective

The purpose of this study is to characterize the MDSCs in the joints of mice with autoimmune arthritis.

Methods

We sorted CD11b+Gr1+ cells from joints (Jo), bone marrow (BM) and spleen (Sp) of SKG mice with zymosan (Zym)-induced arthritis and investigated differentially expressed genes (DEGs) by microarray analysis. Based on the identified DEGs, we assessed the suppressive function of CD11b+Gr1+ cells from each organ and their ability to differentiate into osteoclasts.

Results

We identified MDSCs as CD11b+Gr1+ cells by flow cytometry and morphological analysis. Microarray analysis revealed that Jo-CD11b+Gr1+ cells had different characteristics compared with BM-CD11b+Gr1+ cells or Sp-CD11b+Gr1+ cells. Microarray and qPCR analysis showed that Jo-CD11b+Gr1+ cells strongly expressed immunosuppressive DEGs (Pdl1, Arg1, Egr2 and Egr3). Jo-CD11b+Gr1+ cells significantly suppressed CD4+ T cell proliferation and differentiation in vitro, which confirmed Jo-CD11b+Gr1+ cells as MDSCs. Microarray analysis also revealed that Jo-MDSCs strongly expressed DEGs of the NF-κB non-canonical pathway (Nfkb2 and Relb), which is relevant for osteoclast differentiation. In fact, Jo-MDSCs differentiated into osteoclasts in vitro and they had bone resorptive function. In addition, intra-articular injection of Jo-MDSCs promoted bone destruction.

Conclusions

Jo-MDSCs possess a potential to differentiate into osteoclasts which promote bone resorption in inflamed joints, while they are immunosuppressive in vitro.

Association of large joint involvement at the start of biological disease-modifying antirheumatic drugs and Janus kinase inhibitors with disease activity and drug retention in patients with rheumatoid arthritis: The ANSWER cohort study

AIM

To investigate the association of large joint involvement (LJI) with disease activity and drug retention in patients with rheumatoid arthritis (RA) who started receiving a biological disease-modifying antirheumatic drug or Janus kinase inhibitor.

METHODS

Patients with RA from a Japanese multicenter observational registry were enrolled. Our definition of large joints included the shoulder, elbow, hip, knee, and ankle joints. Linear mixed-effects models were used to examine changes in the clinical disease activity index (CDAI) score at Week 24 as the primary outcome, and drug retention rates were compared between patients with and without LJI using Cox proportional hazards models. We examined the potential effect modifications of changes in the CDAI by baseline characteristics.

RESULTS

Overall, 2507 treatment courses from 1721 patients were included (LJI, 1744; no LJI, 763). Although LJI was associated with significantly higher changes in CDAI from baseline at Week 24 (difference in change in CDAI: -5.84 [-6.65 to -5.03], p < .001), CDAI was significantly higher in patients with LJI over time. Retention rates were similar in both groups. The association of LJI with changes in disease activity was more prominent in patients with a short disease duration, negative anti-citrullinated peptide antibodies, and interleukin-6 receptor inhibitor (IL-6Ri) use.

CONCLUSION

Although LJI was associated with a greater reduction in disease activity from baseline, higher disease activity at baseline was not offset over time in patients with LJI, demonstrating that LJI is an unfavorable predictor. An early treat-to-target strategy using an IL-6Ri may be beneficial for patients with LJI.

Comparison of retention of biologics in Japanese patients with elderly-onset rheumatoid arthritis-the ANSWER cohort study

OBJECTIVES

This multicentre, retrospective study aimed to compare retention and reasons for discontinuation between Janus kinase inhibitors (JAKi) and biologic disease-modifying antirheumatic drugs in patients with elderly-onset rheumatoid arthritis (EORA).

METHODS

Patients with RA enrolled in a Japanese multicentre observational registry between 2015 and 2022 were included. EORA was defined as RA with onset at 60 or over. To adjust confounding factors by indication for initiation of tumor necrosis factor inhibitors (TNFi), interleukin-6 inhibitors (IL-6i), cytotoxic T-lymphocyte associated antigen 4 immunoglobulin (CTLA4-Ig) blockers, or JAKi, a propensity score based on baseline characteristics was used to compare drug retention. To assess the reasons for discontinuation, retention rates for ineffectiveness, adverse events, and remission were analyzed as secondary outcomes.

RESULTS

A total of 572 patients with 835 treatment courses were identified (314 TNFi, 175 IL-6i, 228 CTLA4-Ig, and 118 JAKi). After adjusting for differences in baseline characteristics, drug retention was significantly higher for IL-6i (HR = 0.38, 95%CI = 0.27-0.55, p< 0.01) as compared with TNFi. Discontinuation due to lack of effectiveness was lower with the JAKi (HR = 0.38, 95%CI = 0.22-0.66, p< 0.01) and the IL-6i (HR = 0.29, 95%CI = 0.19-0.46, p< 0.01) as compared with the TNFi although the CTLA4-Ig had a similar HR to TNFi. The adjusted incidence of discontinuation due to adverse event was higher in the JAKi (HR = 2.86, 95%CI = 1.46-5.59, p< 0.01) than the TNFi.

CONCLUSIONS

In EORA patients, IL-6i and JAKi had longer retention and less discontinuation due to ineffectiveness than TNFi. The potential risks of JAKi should be approached with an individualized perspective.

Comparative effectiveness of biological disease-modifying antirheumatic drugs and Janus kinase inhibitor monotherapy in rheumatoid arthritis

OBJECTIVES

To examine the effectiveness and drug tolerability of biological disease-modifying antirheumatic drugs (bDMARDs) and Janus kinase inhibitor (JAKi) monotherapy in patients with rheumatoid arthritis (RA) in a multicentre cohort study.

METHODS

Patients with RA initiated with bDMARD/JAKi monotherapy without conventional synthetic DMARDs were included. Monotherapy regimens were categorised as interleukin-6 receptor inhibitors (IL-6Ri), cytotoxic T-lymphocyte-associated protein 4 immunoglobulin (CTLA4Ig), JAKi, or tumour necrosis factor inhibitors (TNFi). Multiple propensity score-based inverse probability weighting (IPW) was used to reduce selection bias. Linear mixed-effect models with IPW were used to examine changes in the disease activity score in 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) at 24 weeks, and drug retention was compared among monotherapy using IPW Cox proportional hazards models.

RESULTS

A total of 849 treatment courses from 635 patients were included (IL-6Ri, 218; CTLA4Ig, 183; JAKi, 92; TNFi, 356). The difference in change in DAS28-ESR at week 24 as the primary outcome was -0.93 (95% CI: -1.20 to -0.66) lower in the IL-6Ri group than TNFi, while that of CTLA4Ig and JAKi was similar with that of TNFi (-0.20 [-0.48 to 0.08], -0.25 [-0.67 to 0.16], respectively). IL-6Ri use was associated with significantly lower overall drug discontinuation than TNFi use (hazard ratio = 0.55 [0.39-0.78], P = 0.001). Similar retention rates were identified among CTLA4Ig and JAKi compared to TNFi.

CONCLUSION

In the analysis with IPW to reduce selection bias, IL-6Ri monotherapy was superior to TNFi monotherapy in terms of effectiveness and drug retention. No significant differences were identified between CTLA4Ig, JAKi, and TNFi monotherapy.

Real-world comparative study of the efficacy of Janus kinase inhibitors in patients with rheumatoid arthritis: the ANSWER cohort study

OBJECTIVE

This multicentre, retrospective study compared the efficacy and safety of tofacitinib, baricitinib, peficitinib and upadacitinib in real-world clinical settings after minimizing selection bias and adjusting the confounding patient characteristics.

METHOD

The 622 patients were selected from the ANSWER cohort database and treated with tofacitinib (TOF), baricitinib (BAR), peficitinib (PEF) or upadacitinib (UPA). The patient's background was matched using propensity score-based inverse probability of treatment weighting (IPTW) among four treatment groups. The values of Clinical Disease Activity Index (CDAI), C-reactive protein (CRP), and modified Health Assessment Questionnaire (mHAQ) after drug initiation and the remission or low disease activity (LDA) rates of CDAI at 6 months after drug initiation were compared among the four groups. Further, the predictive factor for TOF and BAR efficacy was analysed.

RESULTS

The retention and discontinuation rates until 6 months after drug initiations were not significantly different among the four JAK inhibitors treatment groups. Mean CDAI value, CDAI remission rate, and CDAI-LDA rate at 6 months after drug initiation were not significantly different among treatment groups. Baseline CDAI (TOFA: OR 1.09, P < 0.001; BARI: OR 1.07, P < 0.001), baseline CRP (TOFA: OR 1.32, P = 0.049), baseline glucocorticoid dose (BARI: OR 1.18, 95% CI 1.01-1.38, P = 0.035), a number of previous biological or targeted synthetic disease-modifying antirheumatic drugs (biological/targeted synthetic DMARDs) (BARI: OR 1.36, P = 0.004) were predictive factors for resistance to CDAI-LDA achievement to JAK inhibitor treatment.

CONCLUSION

The efficacy and safety of TOF, BAR, PEF and UPA were not significantly different for the treatment of patients with rheumatoid arthritis.

Association of anti-β2-glycoprotein I/HLA-DR complex antibody with arterial thrombosis in female patients with systemic rheumatic diseases

BACKGROUND

β2-glycoprotein I (β2GPI) complexed with human leukocyte antigen DR (β2GPI/HLA-DR) was found to be a major autoantibody target in antiphospholipid syndrome (APS). This study aimed to reveal the association between anti-β2GPI/HLA-DR antibodies and vascular thromboses in women with systemic rheumatic diseases.

METHODS

We conducted a retrospective longitudinal study. We measured anti-β2GPI/HLA-DR antibodies and compared them with anti-phospholipid antibody (aPL) profiles and the adjusted global antiphospholipid syndrome score (aGAPSS). Using receiver operating characteristic (ROC) analysis, we determined the best cut-off value for arterial thrombosis. We also evaluated the validity of anti-β2GPI/HLA-DR antibodies by adding to conventional cardiovascular risk factors in multivariate logistic analysis.

RESULTS

We evaluated 704 patients, including 66 (obstetric or thrombotic) APS, 13 primary APS, and 78 asymptomatic aPL carriers. Seventy-seven patients had a history of arterial thrombosis, and 14 patients had both arterial and venous thrombosis. These 14 patients, as well as patients with aGAPSS > 10 or triple-positive aPL profiles, displayed high anti-β2GPI/HLA-DR antibody titers. The ROC curve showed a sensitivity, specificity, and area under the curve (AUC) for arterial thrombosis of 33.8%, 91.4%, and 0.6009, respectively, with a cut-off value of 172.359 U/mL. The anti-β2GPI/HLA-DR antibody positivity using this cut-off value yielded an odds ratio of 5.13 (95%CI: 2.85-9.24), significantly improving the AUC from 0.677 to 0.730.

CONCLUSION

Anti-β2GPI/HLA-DR antibodies are associated with arterial thrombosis in female patients with systemic rheumatic diseases.

Trends of disease activity in Japanese patients over 75 years with rheumatoid arthritis from 2014 to 2021- the ANSWER cohort study

OBJECTIVES

To investigate if disease activity among elderly RA patients over 75 years has changed over time in the real-world clinical setting.

METHODS

Data from an observational multicentre registry of RA patients in Japan were analyzed. The primary outcome was to evaluate the changes in the proportion of very elderly RA patients (over 75 years) who achieved remission and low disease activity, from 2014 to 2021. The secondary outcome was to identify factors associated with remission and low disease activity by comparing demographic and clinical characteristics among the patients who had a study visit within the study period, using multivariate logistic regression.

RESULTS

A total of 32 161 patient visits were identified from 2014 to 2021. The proportion of patients over 75 years increased from 16.5% to 26.9%, with biologics and targeted-synthetic disease modifying anti-rheumatic drugs (b/tsDMARDs) usage increasing and glucocorticoids usage decreasing, while conventional-synthetic DMARDs usage remained relatively stable. The proportion of RA patients over 75 years achieving remission and low disease activity significantly increased from 62.2% to 78.2% (p for trend < 0.001). A negative factor associated with achieving remission and low disease activity was glucocorticoid usage, seropositivity, and history of previous b/tsDMARDs use while MTX usage was associated positively, independent of other predictors.

CONCLUSIONS

In our cohort, disease activity among very elderly RA patients has improved over time. The study suggests the importance of using a treat-to-target approach in very elderly RA patients to improve clinical outcomes.

Demographic, Physical, and Psychological Determinants of Patient Experience with Subcutaneous Self-Injection in Patients with Rheumatoid Arthritis: Structural Equation Modeling Approach

Purpose

To achieve a better patient experience with self-injection, an assessment of potential demographic, physical, and psychological barriers is necessary. The aim of this study was to examine the demographic, physical, and psychological characteristics associated with the experiences of self-injection in patients with rheumatoid arthritis (RA).

Patients and Methods

In this study, overall patient experience with subcutaneous self-injection was assessed using the Self-Injection Assessment Questionnaire. Upper limb function was assessed using the three domains of the Health Assessment Questionnaire associated with upper extremity disability (dressing and grooming, eating, and grip). Structural equation modeling was used to estimate the association between the demographic and clinical characteristics of patients with RA and their experiences with self-injection in the theoretical model.

Results

Data from 83 patients with RA were analyzed. Compared with younger patients, elderly patients were more likely to experience lower self-confidence, self-image, and ease of use. Female patients had lower ease of use than male patients. In terms of upper limb function, patients with more difficulty in performing activities of daily living were more likely to have a lower self-image. Self-injection perceptions before learning the method of injection, such as fear of needles and anxiety about self-injection, were associated with post-injection feelings, injection site reactions, self-confidence, and ease of use.

Conclusion

To optimize patients' experiences with self-injection, healthcare workers should assess each patient's age, sex, upper limb function, and pre-self-injection perceptions as demographic, physical, and psychological barriers.

Instability of harmonized thyroid-stimulating hormone immunoassays in clinical practice

OBJECTIVE

Thyroid-stimulating hormone (TSH) harmonization is effective in minimizing differences between the results of immunoassays in healthy subjects. However, the effectiveness of TSH harmonization in clinical practice has not been investigated. The aim of this study was to evaluate the instability of TSH harmonization in clinical practice.

METHODS

We compared the reactivities of four harmonized TSH immunoassays using combined difference plots of 431 patients. We selected patients with statistically significant deviations in TSH levels and analyzed their thyroid hormone levels and clinical characteristics.

RESULTS

The combined difference plots showed that one harmonized TSH immunoassay exhibited markedly different reactivity even after TSH harmonization compared with the other three immunoassays. Among 109 patients with mild-to-moderate elevation of TSH levels, we selected 15 patients with statistically significant deviations in TSH levels according to the difference plots of three harmonized TSH immunoassays, excluding one immunoassay that showed different reactivity. The thyroid hormone levels of three patients were misclassified as hypothyroidism or normal due to deviating TSH levels. In terms of clinical characteristics, these patients were in poor nutritional status and general condition, possibly due to their severe illness (e.g., advanced metastatic cancer).

CONCLUSION

We have confirmed that TSH harmonization in clinical practice is relatively stable. However, some patients showed deviating TSH levels in the harmonized TSH immunoassays, indicating the need for caution, particularly in poorly nourished patients. This finding suggests the presence of factors that contribute to the instability of TSH harmonization in such cases. Further investigation is warranted to validate these results.

Severe Lupus Myocarditis Preceded by Mesalazine-induced Lupus

In drug-induced lupus (DIL), symptoms similar to those of systemic lupus erythematosus (SLE) usually resolve after discontinuation of the offending drug. A 41-year-old-woman with a history of ulcerative colitis presented with polyarthritis and myositis and was positive for anti-double stranded (ds) DNA IgG antibody. After discontinuation of mesalazine, the symptoms resolved, and the antibody titer decreased. The patient was diagnosed with DIL. Six months later, lupus myocarditis developed. After treatment with glucocorticoids, cyclophosphamide, intravenous immunoglobulin, and an intra-aortic balloon pump, she showed dramatic improvement. Patients with DIL and an immunological predisposition, such as anti-dsDNA antibodies, may have SLE and should be carefully monitored.

Association of Neonatal Serum Creatinine Concentration with Maternal Serum Creatinine Concentration and Birth Weight

BACKGROUND

The serum creatinine (SCr) concentration in neonates is generally high for its body size, compared to those of infants. The aim of the present study was to investigate the effect of maternal SCr on neonatal SCr through measurements of prenatal maternal SCr and neonatal SCr from birth to postnatal Day 5. In addition, postnatal changes in SCr were compared between term and preterm infants, given that few studies have addressed this topic.

METHODS

The retrospective study subjects were 151 neonates whose Scr was measured consecutively from birth to postnatal Day 5 and 124 mothers whose SCr was measured prenatally.

RESULTS

There were significant correlations between maternal SCr and neonatal SCr at birth (r = 0.858, p < 0.001) and on postnatal Day 1 (r = 0.235, p < 0. 001). The SCr of term infants (median 0.69 mg/dL, range 0.54 - 0.96 mg/ dL) were higher than those of preterm infants (median 0.63 mg/dL, range 0.43 - 1.23 mg/dL, p < 0.001) at birth; however, these values were reversed on postnatal Day 1 (Term: median 0.75 mg/dL, range 0.51 - 1.13 mg/dL, Pre-term: median 0.88 mg/dL, range 0.56 - 1.25 mg/dL, p < 0.001). There were differences in the timing of reaching to peak SCr between preterm and term neonates. In addition, birth weight might affect SCr concentrations after birth.

CONCLUSIONS

The results of this study suggest that neonatal SCr is influenced by maternal SCr, although the effect disappears by postnatal Day 2. Moreover, glomerular filtration rate differs between term and preterm infants.

Exosomes derived from synovial fibroblasts from patients with rheumatoid arthritis promote macrophage migration that can be suppressed by miR-124-3p

Objectives

Exosomes are potent vehicles for intercellular communication. Rheumatoid arthritis (RA) is a chronic systemic disease of unknown etiology. Local administration of miR-124 precursor to rats with adjuvant-induced arthritis suppresses systemic arthritis and bone destruction. Thus, exosomes may be involved in this disease. We aimed to determine the role of exosomes in the pathology of RA.

Methods

Fibroblast-like synoviocytes (FLS) were collected from patients with RA and osteoarthritis (OA). miR-124-3p mimic was transfected into the RA FLS (RA miR-124 FLS). Exosomes were collected from the culture medium by ultracentrifugation. Macrophages were produced from THP-1 cells. MicroRNAs in the exosomes were analyzed using real-time PCR. Proteomics analysis was performed using nanoscale liquid chromatography-tandem mass spectrometry. Macrophage migration was evaluated using a Transwell migration assay. SiRNA was used to knockdown proteins of interest.

Results

MicroRNAs in the RA FLS, RA miR-124 FLS, and OA FLS exosomes were similar. Proteomics analysis revealed that pentraxin 3 (PTX3) levels were higher in RA FLS exosomes than in RA miR-124 FLS and OA FLS exosomes, and proteasome 20S subunit beta 5 (PSMB5) levels were lower in RA FLS exosomes than in RA miR-124 FLS and OA FLS exosomes. The RA FLS exosomes promoted and the RA miR-124 FLS exosomes suppressed macrophage migration. PTX3-silenced RA FLS exosomes suppressed and PSMB5-silenced OA FLS exosomes promoted macrophage migration.

Conclusions

RA FLS exosomes promote macrophage migration via PTX3 and PSMB5, and miR-124-3p suppresses this migration.

Comparison of 17 serological treponemal and nontreponemal assays for syphilis: A retrospective cohort study

Objectives

Rapid plasma reagin (RPR) and Treponema pallidum (TP) antibody test kits are often used to diagnose syphilis, although the relationship between their measured values is unclear. We aimed to reveal the relevance of these kits’ results.

Design and methods

In all, 143 sera from 110 patients were tested using 12 TP kits and 5 RPR kits and the results compared.

Results

The specificity and sensitivity of RPR kits were 81–96% and 95–100%, respectively. The correlation coefficients (0.849–0.934) considerably differed between the manual RPR card test and latex agglutination (LA) assay kits. The following sensitivities were obtained: 82–91% for TP fluorescent treponemal antibody absorption assay (FTA-ABS), TP hemagglutination assay (HA), and TP particle agglutination assay (PA); 94–95% for TP LAs; and 92–100% for chemiluminescent immunoassay (CLIA), chemiluminescent enzyme immunoassay (CLEIA), and immunochromatography assay (IC). Correlation coefficients between TP kits were 0.753–0.974, and the measured values varied. Changes in RPR and quantifiable TP kits were the same for patients with reinfected syphilis and with syphilis under treatment.

Conclusions

RPR tests had lower specificity than TP antibody tests. RPR card test and RPR LAs had similar specificity and sensitivity, but their measured values were different. RPR should be measured using automatic RPR LA without setting the upper limit of the reported value. RPR LA should also be standardized. The sensitivity of TP antibody was better in CLIA, CLEIA, and IC than in FTA-ABS, HA, PA, and LA. Therefore, TP antibody kits should be standardized and quantified.

•

RPR CT and four RPR LAs have similar specificity and sensitivity.

•

RPR CT and four RPR LAs have different measured values.

•

CLIA, CLEIA, and IC have more sensitive TP antibodies than other tests.

•

The measured values of 12 TP antibody kits vary.

•

Quantitative TP antibodies are similar to RPR in the clinical course of syphilis.

POS0432 MDSCs IN THE INFLAMMATORY JOINT OF SKG MICE HAVE BOTH T CELL SUPPRESSIVE ABILITY AND OSTEOCLAST DIFFERENTIATION POTENTIAL

Background

Myeloid-derived suppressor cells (MDSCs) are heterogeneous immature myeloid cells with suppressive functions (1). It is known that MDSCs are expanded in inflammatory sites after migrating from bone marrow (BM) or spleen. Rheumatoid arthritis (RA) is an autoimmune disease characterized as polyarthritis. Although previous reports indicate that MDSCs are increased in BM and spleen of arthritis model mice, detailed analysis of MDSCs in inflammatory joints is limited.

Objectives

The purpose of this study is to characterize the MDSCs in the joints of autoimmune arthritis.

Methods

We isolated CD11b+Gr1+ cells as MDSCs from joints (Jo-MDSCs), bone marrow (BM-MDSCs) and spleen (Sp-MDSCs) of arthritis-induced SKG mice, and investigated differential expressed genes (DEGs) among MDSCs from three tissues by microarray expression analysis. Furthermore, we analyzed the suppressive function of each MDSCs by investigating the effect of them on T cell -proliferation and the osteoclast differentiation of each MDSCs stimulated by M-CSF and RANKL.

Results

Microarray analysis revealed that Jo-MDSCs highly expressed immunosuppressive DEGs (Pdl1, Arg1, Egr2 and Egr3) compared to BM MDSCs or Sp MDSCs. In addition, Jo-MDCSs highly expressed NF-κB non-canonical pathway DEGs (Nfkb2 and Relb), which are related to osteoclast differentiation. BM-MDSCs differentiated into osteoclasts but didn’t suppress T cell-proliferation and Sp-MDSCs suppressed T cell-proliferation but didn’t differentiate into osteoclasts. On the other hand, Jo-MDSCs was found to have both functions: T cell suppression and osteoclast differentiation potential.

Conclusion

Jo-MDSCs have a strong inhibitory effect on T cell proliferation and have the ability osteoclast differentiation potential.

References

[1]Veglia F, Perego M, Gabrilovich D. Myeloid-derived suppressor cells coming of age. Nat Immunol. 2018;19(2):108–19.

Disclosure of Interests

None declared.

AB0036 BUTYRIC ACID SUPPRESSES MIGRATION OF MONOCYTE-DERIVED DENDRITIC CELLS BY INHIBITING MDIA1-MEDICATED ACTIN POLYMERIZATION

Background

Butyric acid is known to improve chronic inflammation such as inflammatory bowel disease and arthritis [1, 2]. Dendritic cells activate in inflammatory condition, migrate to regional lymph nodes, and activate naive T cells.

Objectives

In this study, we investigated the effect of butyric acid on the migration ability of monocyte-derived dendritic cells (moDC).

Methods

Human CD14+ Monocytes were purified by positive selection from PBMC using CD14 magnetic beads. Cells were cultured in the presence of GM-CSF (50 ng/ml) and IL-4 (20 ng/ml) for 5 days. After culturing for 5 days, cells were matured with LPS (1ug/ml) for 24 hours. Butyric acid was administered at different dose or period. Surface antigen on moDC was analyzed by flow cytometry (BD FACS VERSE). Migration assay was performed on Boyden chamber CytoSelect 24-Well Cell Migration Assay (5um). Actin was stained with Alexa Fluor 488 Phalloidin before and after migration assay. After administration with butyric acid assigned to each period and concentration, moDC were lysed for western blot analysis for evaluating signaling. Chemiluminescent signals were detected and calculated by Amersham Imager.

Results

We demonstrated that butyric acid decreased the CCR7 expression of moDC, which has a key role in DC homing to the lymph nodes and intestinal Peyer’s patches. We also showed that butyric acid decreased the migration ability of moDC. Furthermore, moDCs cultured with butyric acid showed a round shape and poor formation of dendrites and pseudopodia. Then we studied the effect of butyric acid on cytoskeleton, which plays an important role in migration and pseudopodia formation of DCs. Polymerized Actin (F-Actin) staining revealed that butyrate suppressed actin polymerization of moDC in a dose dependent manner. CDC42 works important role of lamellipodia and membrane protrusions. RhoA is upstream of mDia1, and mDia1 was reported to accelerate actin nucleation and elongation. We revealed that butyrate decreased the protein expression of mDia1, RhoA, and CDC42, while beta actin was not downregulated, by Western blot analysis. Our results suggested that butyric acid suppresses migration of moDCs by inhibiting mDia1-medicated actin polymerization.

Conclusion

Butyric acid suppresses migration of moDCs by inhibiting mDia1-medicated actin polymerization.

References

[1]Mafalda R Couto 1, Pedro Gonçalves 2, Fernando Magro 3, Fátima Martel, et al. Microbiota-derived butyrate regulates intestinal inflammation: Focus on inflammatory bowel disease Pharmacol Res. 2020 Sep;159:104947.

[2]Wenpeng Hui, Dapeng Yu, Zhong Cao, Xiwu Zhao, et al. Butyrate inhibit collagen-induced arthritis via Treg/IL-10/Th17 axis Int Immunopharmacol. 2019 Mar;68:226-233.

Disclosure of Interests

None declared

Large-scale serosurveillance of COVID-19 in Japan: Acquisition of neutralizing antibodies for Delta but not for Omicron and requirement of booster vaccination to overcome the Omicron's outbreak

Continuous appearance of SARS-CoV-2 variants and mass vaccination have been intricately influencing on the COVID-19 situation. To elucidate the current status in Japan, we analyzed totally 2,000 sera in August (n = 1,000) and December (n = 1,000) 2021 collected from individuals who underwent a health check-up. The anti-N seropositive rate were 2.1% and 3.9% in August and December 2021, respectively, demonstrating a Delta variant endemic during that time; it was approximately twofold higher than the rate based on the PCR-based diagnosis. The anti-S seropositive rate was 38.7% in August and it reached 90.8% in December, in concordance with the vaccination rate in Japan. In the December cohort, 78.7% of the sera showed neutralizing activity against the Delta variant, whereas that against the Omicron was much lower at 36.6%. These analyses revealed that effective immunity against the Delta variant was established in December 2021, however, prompt three-dose vaccination is needed to overcome Omicron’s outbreak.

Effect of resolvin D5 on T cell differentiation and osteoclastogenesis analyzed by lipid mediator profiling in the experimental arthritis

Resolvins, are specialized pro-resolving mediators (SPMs) derived from n-3 polyunsaturated fatty acids. They contribute actively to the resolution of inflammation, but little is known concerning their role in chronic inflammation, such as in rheumatoid arthritis (RA). Here, we performed lipid mediator (LM) profiling in tissues from the paws of SKG arthritic mice using lipid chromatography (LC)/mass spectrometry (MS)/MS-based LM metabololipidomics. We found elevated levels of SPMs including resolvin D5 (RvD5) in these tissues. Moreover, RvD5 levels were significantly correlated with arthritis disease activity. From experiments to assess the role of RvD5 in the pathology of RA, we concluded that RvD5 suppressed Th17 cell differentiation and facilitated regulatory T cell differentiation, as well as inhibiting CD4⁺ T cell proliferation. Furthermore, RvD5 attenuated osteoclast differentiation and interfered with osteoclastogenesis. Targeting the resolution of inflammation could be promising as a novel treatment for RA.

Identification of Plexin D1 on circulating extracellular vesicles as a potential biomarker of polymyositis and dermatomyositis

OBJECTIVES

We aimed to identify disease-specific surface proteins on extracellular vesicles (EVs) as novel serum biomarkers of polymyositis and dermatomyositis (PM/DM).

METHODS

We performed liquid chromatography-tandem mass spectrometry (LC/MS) on purified EVs from sera of 10 PM/DM, 23 patients with other autoimmune diseases and 10 healthy controls (HC). We identified membrane proteins preferentially present in EVs of PM/DM patients by bioinformatics and biostatistical analyses. We developed EV sandwich ELISA for directly detecting serum EVs expressing disease-specific membrane proteins and evaluated their clinical utility using sera of 54 PM/DM, 24 rheumatoid arthritis (RA), 20 systemic lupus erythematosus (SLE), 13 systemic sclerosis, 25 Duchenne and Becker muscular dystrophy (DMD/BMD) patients, and 36 HC.

RESULTS

LC/MS analysis identified 1,220 proteins in serum EVs. Of these, Plexin D1 was enriched in those from PM/DM patients relative to HC or patients without PM/DM. Using a specific EV sandwich ELISA, we found that levels of Plexin D1-positive EVs (Plexin D1+ EVs) in serum were significantly greater in PM/DM patients than in HC, RA or SLE, or DMD/BMD patients. Serum levels of Plexin D1+ EVs were greater in those PM/DM patients with muscle pain or weakness. Serum levels of Plexin D1+ EVs were significantly correlated with levels of aldolase (rs=0.481), white blood cells (rs=0.381), neutrophils (rs=0.450), and platelets (rs=0.408) in PM/DM patients. Finally, serum levels of Plexin D1+ EVs decreased significantly in patients with PM/DM in clinical remission after treatment.

CONCLUSION

We have identified levels of circulating Plexin D1+ EVs as a novel serum biomarker for PM/DM.

Comparative effectiveness of trimethoprim-sulfamethoxazole versus atovaquone for the prophylaxis of pneumocystis pneumonia in patients with connective tissue diseases receiving prolonged high-dose glucocorticoids

We compared the prophylactic effect of trimethoprim-sulfamethoxazole (TMP-SMX) with atovaquone for pneumocystis pneumonia (PCP) in patients with connective tissue diseases (CTDs) receiving high-dose glucocorticoids. Patients with CTDs aged ≥ 18 years who were treated with a prolonged course (≥ 4 weeks) of glucocorticoids (≥ 20 mg/day prednisone) in a Japanese tertiary center between 2013 and 2017 were included. The patients were categorized into two groups: TMP-SMX and atovaquone group. Adjusted cumulative incidence of PCP was compared between the two groups after propensity score weighting for differences in confounding factors. A total of 480 patients with a prolonged high-dose glucocorticoid treatment were identified. Out of 383 patients with TMP-SMX prophylaxis, 102 (26.8%) patients experienced adverse events leading to discontinuation within 4 weeks of initiation, while no patient in the atovaquone discontinued the therapy. Two hundred eighty-one patients received TMP-SMX, while 107 received atovaquone for PCP prophylaxis. During a total of 397.0 person-years, 7 PCP cases (2 in the TMP-SMX, 5 in the atovaquone) occurred with a mortality rate of 54.5%. After adjusting for differences in baseline characteristics, the adjusted cumulative incidence of PCP was similar between the two group (HR 0.97, 95% CI 0.19-5.09, p = 0.97). Prophylactic effects for PCP in CTDs patients receiving prolonged high-dose glucocorticoids were similar between TMP-SMX and atovaquone. Atovaquone was well-tolerated with no side effects.

Soluble guanylate cyclase stimulator reduced the gastrointestinal fibrosis in bleomycin-induced mouse model of systemic sclerosis

BACKGROUND

Systemic sclerosis (SSc) is a chronic autoimmune-mediated connective tissue disorder. Although the etiology of the disease remains undetermined, SSc is characterized by fibrosis and proliferative vascular lesions of the skin and internal organs. SSc involves the gastrointestinal tract in more than 90 % of patients. Soluble guanylate cyclase (sGC) stimulator is used to treat pulmonary artery hypertension (PAH) and has been shown to inhibit experimental skin fibrosis.

METHODS

Female C57BL/6J mice were treated with BLM or normal saline by subcutaneous implantation of osmotic minipump. These mice were sacrificed on day 28 or day 42. Gastrointestinal pathologies were examined by Masson Trichrome staining. The expression of fibrosis-related genes in gastrointestinal tract was analyzed by real-time PCR, and the levels of collagen in the tissue were measured by Sircol collagen assay. To evaluate peristaltic movement, the small intestinal transport (ITR%) was calculated as [dyeing distance × (duodenum - appendix)] - 1 × 100 (%). We treated BLM-treated mice with sGC stimulator or DMSO orally and analyzed them on day 42.

RESULTS

Histological examination revealed that fibrosis from lamina propria to muscularis mucosa in the esophagus was significantly increased in BLM-treated mice, suggesting that BLM induces esophageal hyperproliferative and prefibrotic response in C57BL/6J mice. In addition, the gene expression levels of Col3a1, CCN2, MMP-2, MMP-9, TIMP-1, and TIMP-2 in the esophagus were significantly increased in BLM-treated mice. More severe hyperproliferative and prefibrotic response was observed in the mice sacrificed on day 42 than the mice sacrificed on day 28. The ITR% was found to be significantly lower in BLM-treated mice, suggesting that gastrointestinal peristaltic movement was reduced in BLM-treated mice. Furthermore, we demonstrated that sGC stimulator treatment significantly reduced hyperproliferative and prefibrotic response of esophagus and intestine in BLM-treated mice, by histological examination and Sircol collagen assay.

CONCLUSIONS

These findings suggest that BLM induces gastrointestinal hyperproliferative and prefibrotic response in C57BL/6J mice, and treatment with sGC stimulator improves the BLM-induced gastrointestinal lesion.

Comparison of the drug retention and reasons for discontinuation of tumor necrosis factor inhibitors and interleukin-6 inhibitors in Japanese patients with elderly-onset rheumatoid arthritis-the ANSWER cohort study

BACKGROUND

This multi-center, retrospective study aimed to clarify retention rates and reasons for discontinuation of either tumor necrosis factor inhibitors (TNFi) or interleukin-6 inhibitors (IL-6i) in patients with elderly-onset rheumatoid arthritis (EORA).

METHODS

Patients with rheumatoid arthritis (RA) enrolled in a Japanese multicenter observational registry between 2011 and 2020 were included. EORA was defined as RA with onset at 60 or over. To adjust confounding by indication for treatment with TNFi or IL-6i, a propensity score based on multiple baseline characteristics variables was used to compare the drug retention and causes for discontinuation between TNFi and IL-6i. Adjusted cumulative incidence of drug discontinuation for each reason was compared between the two groups using the Fine-Gray model.

RESULTS

Among a total of 9,550 patients in the registry, 674 TNFi and 297 IL-6i initiators with EORA were identified. Age, the proportion of females, disease duration, and baseline disease activity at the time of TNFi or IL-6i initiation were similar between the two groups. After adjusting for differences in baseline characteristics between the two groups, overall drug discontinuation was significantly lower in the IL-6i as compared to the TNFi (HR = 0.71, 95%CI = 0.59-0.86, p < 0.001). The adjusted cumulative incidence of discontinuation due to lack of effectiveness was lower with the IL-6i (HR = 0.46, 95%CI = 0.33-0.63, p < 0.001) while those due to adverse events (HR = 0.82, 95%CI = 0.56-1.18, p = 0.28) or achievement of clinical remission (HR = 1.09, 95%CI = 0.62-1.91, p = 0.76) were similar between the two groups.

CONCLUSIONS

In EORA patients initiating a TNFi or IL-6i, significantly higher drug retention was observed with IL-6i. Discontinuation due to lack of effectiveness was significantly less frequent in IL-6i while discontinuations due to adverse event or achievement of clinical remission were similar between the two groups.

Genetic Analysis of UGT1A1 Polymorphisms Using Preserved Dried Umbilical Cord for Assessing the Potential of Neonatal Jaundice as a Risk Factor for Autism Spectrum Disorder in Children

Neonatal jaundice has been suggested as a perinatal risk factor for autism spectrum disorder (ASD). We examined UGT1A1 polymorphisms to assess the potential of neonatal jaundice as a risk factor for ASD in children by using DNA extracted from preserved umbilical cord. In total, 79 children with ASD were genotyped for UGT1A1*28 (c.-41-40dup), UGT1A1*6 (c.211 G > A), and UGT1A1*27 (c.686 C > A). The allele frequency of UGT1A1*6 (OR = 1.34, p = 0.26) and UGT1A1*28 (OR = 0.80, p = 0.54) and the prevalence of UGT1A1*28/*6 diplotypes did not differ significantly from those in the control population. No UGT1A1*27 allele was detected in the subjects. ASD symptom assessment scores were not associated with UGT1A1*28/*6/*27 genotypes or UGT1A1*28/*6 diplotypes. These results suggest that neonatal jaundice is not significantly associated with ASD.

Prevalence of anti-dense fine speckled 70 antibodies in healthy individuals and patients with antinuclear antibody-associated autoimmune rheumatic diseases in Japan

Previous studies from various countries have reported anti-dense fine speckled pattern (DFS)70 antibody prevalence but few studies have been from Asia. We investigated the prevalence of anti-DFS70 autoantibodies in a Japanese cohort of healthy individuals (HI) and patients with antinuclear antibody-associated autoimmune rheumatic diseases (AARD).Enzyme-linked immunosorbent assay and indirect immunofluorescence were performed using samples from 250 HI and 276 AARD patients.The overall anti-DFS70 antibody prevalence in HI was 16.4%, with 12.8% for males and 20.0% for females (sex difference; P = .12). In AARD patients, the anti-DFS70 antibody prevalence in systemic lupus erythematosus, mixed connective tissue disease, systemic sclerosis, dermatomyositis and polymyositis (DM/PM), Sjögren syndrome, and rheumatoid arthritis (RA) was 22.1%, 14.3%, 14.3%, 3.0%, 21.3%, and 18.1%, respectively (no significant difference between AARD patients except DM/PM and HI). The prevalence of isolated anti-DFS70 antibody in HI and all AARD patients excluding RA was 14.8% (37/250) and 4.4% (9/204), respectively (P  < .01 vs HI). Among anti-DFS70 antibody-positive cases, 63.4% (26/41) were DFS pattern by IIF and 23.5% (8/34) were HI and AARD patients excluding RA, respectively.The anti-DFS70 antibody prevalence in HI and AARD patients in Japan was similar. Furthermore, the anti-DFS70 antibody prevalence in HI and AARD in Japan is higher than in HI and AARD in regions other than Asia. This makes AARD differential diagnosis by antinuclear antibody screening difficult.

Expression of a novel type of KMT2A/EPS15 fusion transcript in FLT3 mutation-positive B-lymphoblastic leukemia with t(1;11)(p32;q23)

The t(1;11)(p32;q23) translocation is a rare but recurrent cytogenetic aberration in acute myeloid leukemia (AML) and B-cell acute lymphoblastic leukemia (B-ALL). This translocation was initially shown to form a fusion gene between KMT2A exon 8 at 11q23 and EPS15 exon 2 at 1p32 in AML. Activating mutations of FLT3 are frequently found in AML but are very rare in ALL. Here, we describe a 75-year-old woman who was diagnosed with B-ALL since her bone marrow was made up of 98.2% lymphoblasts. These blasts were positive for CD19, CD22, CD79a, CD13, and CD33 but negative for CD10 and myeloperoxidase. The karyotype by G-banding and spectral karyotyping was 46,XX,t(1;11)(p32;q23). Expression of KMT2A/EPS15 and reciprocal EPS15/KMT2A fusion transcripts were shown: KMT2A exon 8 was in-frame fused to EPS15 exon 12, indicating that this fusion transcript was a novel type. Considering three reported B-ALL cases, EPS15 breakpoints were markedly different between AML (exon 2) and B-ALL (exons 10-12). Furthermore, an uncommon type of FLT3 mutation in the juxtamembrane domain was detected: in-frame 4-bp deletion and 10-bp insertion. Accordingly, our results indicate that the novel type of KMT2A/EPS15 fusion transcript and FLT3 mutation may cooperate in the pathogenesis of adult B-ALL as class II and class I mutations, respectively.

Seroepidemiological Survey of the Antibody for Severe Acute Respiratory Syndrome Coronavirus 2 with Neutralizing Activity at Hospitals: A Cross-sectional Study in Hyogo Prefecture, Japan

Introduction:

The coronavirus disease 2019 (COVID-19) pandemic is spreading rapidly all over the world. The Japanese government lifted the state of emergency, announced in April 2020, on May 25, but there are still sporadic clusters. Asymptomatic patients who can transmit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cause some of these clusters. It is thus urgent to investigate the seroprevalence of antibodies against SARS-CoV-2 and their neutralizing activity. We conducted a cross-sectional study of >10,000 samples at hospitals in Hyogo Prefecture, Japan.

Methods:

Between August 6 and October 1, 2020, we collected samples of residual blood from the patients who visited or were admitted to five hospitals and a foundation in Hyogo. We tested the samples for antibodies against SARS-CoV-2 by electrochemiluminescence immunoassay (ECLIA) and chemiluminescent enzyme immunoassay (CLEIA). Sera that were positive by ECLIA or CLEIA were analyzed by an immunochromatographic (IC) test and neutralizing activity assay.

Results:

We tested 10,377 samples from patients aged between 0 and 99 years old; 27 cases (0.26%) were positive on the ECLIA, and 51 cases (0.49%) were positive on CLEIA. In the 14 cases that tested positive on both ECLIA and CLEIA, the positive rates on the IC test and for neutralizing activity were high (85% and 92%, respectively). In 50 cases (0.48%) that were positive by either ECLIA or CLEIA, the corresponding rates were low (20% and 6%, respectively). The positive rate of neutralizing antibody was 0.15%.

Conclusions:

These results indicate that most Hyogo Prefecture residents still do not have antibodies and should avoid the risk of incurring a SARS-CoV-2 infection. Two or more antibody tests should be required for seroepidemiological studies of the antibody for SARS-CoV-2, and a neutralizing activity assay is also essential.

Soluble CD14 Induces Pro-inflammatory Cytokines in Rheumatoid Arthritis Fibroblast-Like Synovial Cells via Toll-Like Receptor 4

Objectives: Synovial fluids of rheumatoid arthritis (RA) patients commonly contain high concentrations of soluble CD14 (sCD14). To investigate its potential role in RA pathogenesis, we tested whether sCD14 binding transmits a signal to fibroblast-like synoviocytes from RA patients (RA-FLS). Methods: The induction of pro-inflammatory cytokines, chemokines, and mediators by sCD14 stimulation of RA-FLS was quantified by real-time PCR and ELISA. Cell proliferation was assessed by the BrdU assay. LPS-RS, a Toll-like receptor 4 (TLR-4) antagonist, was used to block TLR-4 signaling. Results: Soluble CD14 induced the expression of IL-6 mRNA and secretion of the protein. The expression of other pro-inflammatory cytokines and mediators, such as TNF-α, IL-8, intercellular adhesion molecule-1 (ICAM-1), MMP-3, and RANK ligand (RANKL), was also induced by sCD14. In addition, sCD14 stimulation promoted RA-FLS proliferation. LPS-RS abolished IL-6, IL-8, and ICAM-1 mRNA induction by sCD14 in RA-FLS. On the other hand, TNF-α and IL-17A increased TLR-4 expression by RA-FLS and amplified their sCD14-induced IL-6 expression. Conclusions: Soluble CD14 transmits inflammatory signals to RA-FLS via TLR-4. The effects of sCD14 may be augmented in inflammatory milieu. Our results suggest that sCD14 is involved in the pathogenesis of RA and may be a novel therapeutic target.

SAT0011 COMBINED INHIBITION OF AUTOPHAGY AND GLUTAMINE METABOLISM SUPPRESSES CELL GROWTH OF RA SYNOVIOCYTES AND AMELIORATES ARTHRITIS IN SKG MICE

Background:

Immunometabolism is now recognaized to be crucial in the pathogenesis of rheumatoid arthritis (RA). We have recently shown that the expression of glutaminase 1 (GLS1), a key enzyme in glutaminolysis, is upregulated in fibroblast-like synoviocytes from RA patients (RA-FLS) and that GLS1 inhibition suppresses RA-FLS proliferation (1). However, glutaminolysis has been known to suppress autophagy by activating mTORC1 or counteracting ROS production (2). Given the possibility of autophagy upregulation following glutamiolysis inhibition, therapies targeting both autophagy and glutaminolysis may be more effective in suppressing cell growth of RA-FLS, yet the relation between glutaminolysis and autophagy in RA-FLS has not been investigated.

Objectives:

To examine the effects of inhibiting both glutaminolysis and autophagy on RA-FLS and autoimmune arthritis in SKG mice.

Methods:

GLS1 inhibitor, compound 968 (C968), was used to suppress glutaminolysis, and Chloroquine (CQ) was used to inhibit autophagy. To detect autophagy, the expression of ATG5 and LC3B was measured by real-time PCR and the production of LC3-II was analyzed by Western blotting. The formation of autophagic vacuoles was identified by immunfluorescense. Cell growth was evaluated by BrdU assay. Apoptosis was analyzed by flow cytometry staining with Annexin V-FITC and PI. C968 and CQ were administered subcutaneously to Zymosan A-injected SKG mice.

Results:

C968 upregulated the expression of ATG5 and LC3B, and increased the protein level of LC3-II in RA-FLS. C968 also facilitated autophagosome formation. These results suggested that inhibition of glutaminolysis promoted autophagy in RA-FLS. The combined treatment with C968 and CQ significantly suppressed cell proliferation of RA-FLS more strongly than did C968 or CQ alone. In addition, C968 combined with CQ increased the apoptosis rate, whereas either C968 or CQ alone did not. Furthermore, combination of C968 and CQ significantly attenuated the degree of arthritis in SKG mice, while C968 or CQ monotherapy did not (Figure).

Conclusion:

The GLS1 inhibitor C968 promotes autophagy in RA-FLS. C968 in combination with CQ reduces proliferation and enhances apoptosis in RA-FLS, and ameliorates the arthritis in SKG mice. Suppressing C968-induced autophagy may be a promising therapy for arthritis.

References:

[1] Takahashi S., et al. Arthritis Res Ther. 2017 Apr 11;19(1):76.

[2] Villar VH., et al. Autophagy. 2015;11(8):1198-208.

Acknowledgments :

None

Disclosure of Interests:

None declared

SAT0222 CLINICAL SPECTRUM AND LONG TERM FOLLOWUP OF SYSTEMIC LUPUS ERYTHEMATOSUS-ASSOCIATED MACROPHAGE ACTIVATION SYNDROME

Background:

Systemic lupus erythematosus (SLE) patients present with variable clinical features ranging from mild joint and skin involvement to life-threatening organ involvement such as nephritis, neuropsychiatric involvement, diffuse alveolar hemorrhage, and hemophagocytic lymphohistiocytosis (HLH). HLH is rare, but fatal complication of SLE. Recently, European League Against Rheumatism, the American College of Rheumatology, and the Pediatric Rheumatology International Trials Organization was to develop a set of classification criteria for MAS complicating systemic juvenile idiopathic arthritis (PRINTO criteria) [1]. Sung Soo Ahn and his colleagues reported PRINTO criteria predicted mortality of adult SLE patient, but they followed only one year [2].

Objectives:

To reveal association PRINTO criteria with long term mortalities in SLE patient in our Hospital.

Methods:

We performed a retrospective analysis of SLE patients who received moderate dose glucocorticoid therapy (>0.4mg/kg/d) in our hospital between April 2008 and April 2019. Patients were evaluated for HLH using the 2016 PRINTO classification criteria for MAS. Clinical features and laboratory findings were compared and overall survival rate was analyzed.

Results:

Among 164 episode (144 patients) with SLE, 31 episode (31 patients) 5.2% were considered to have MAS on admission.

The overall survival rate was significantly lower in patients with MAS than without MAS (86.2% vs. 95.3%, p = 0.048). Interestingly, SLEDAI had no association with mortality, relapse rate, and MAS complication. SLEDAI more focused on renal and neuropsychiatric symptoms than hematologic features. So SLEDAI might not be associated with MAS secondary to SLE. Furthermore, we observed no death patient with MAS after one year, and only 1 case relapse in MAS patient. So MAS might have fatal but less relapsing property compared with other lupus cases.

Conclusion:

PRINTO criteria may be useful to differentiated fatal MAS patients from others. Further investigations are required to confirm our findings.

Limitation:

The main limitations of our study include its retrospective design, single center site, and that the number of admitted patients with SLE was small.

Limitation:

Limitation The main limitations of our study include its retrospective design, single center site, and that the number of admitted patients with SLE was small.

References:

[1]Wulffraat N, Schneider R, Filipovic L, et al. 2016 Classification Criteria for Macrophage Activation Syndrome Complicating Systemic Juvenile Idiopathic Arthritis. Ann Rheum Dis 2016;75:481–9.

[2]Ahn SS, Yoo BW, Jung SM, et al. In-hospital mortality in febrile lupus patients based on 2016 EULAR/ACR/PRINTO classification criteria for macrophage activation syndrome. Semin Arthritis Rheum 2017;47:216–21.

Disclosure of Interests:

None declared

Biomarkers identified by serum metabolomic analysis to predict biologic treatment response in rheumatoid arthritis patients

OBJECTIVES

Biologic treatment has recently revolutionized the management of RA. Despite this success, ∼30-40% of the patients undergoing biologic treatment respond insufficiently. The aim of this study was to identify several specific reliable metabolites for predicting the response of RA patients to TNF-α inhibitors (TNFi) and abatacept (ABT), using capillary electrophoresis-time-of-flight mass spectrometry (CE-TOFMS).

METHODS

We collected serum from RA patients with moderate or high disease activity prior to biologic treatment, and obtained the serum metabolomic profiles of these samples using CE-TOFMS. The patients' response was determined 12 weeks after starting biologic treatment, according to the EULAR response criteria. We compared the metabolites between the response and non-response patient groups and analysed their discriminative ability.

RESULTS

Among 43 total patients, 14 of 26 patients in the TNFi group and 6 of 17 patients in the ABT group responded to the biologic treatment. Of the metabolites separated by CE-TOFMS, 196 were identified as known substances. Using an orthogonal partial least-squares discriminant analysis, we identified five metabolites as potential predictors of TNFi responders and three as predictors of ABT responders. Receiver operating characteristic analyses for multiple biomarkers revealed an area under the curve (AUC) of 0.941, with a sensitivity of 85.7% and specificity of 100% for TNFi, and an AUC of 0.985, with a sensitivity of 100% and specificity of 90.9% for ABT.

CONCLUSION

By metabolomic analysis, we identified serum biomarkers that have a high ability to predict the response of RA patients to TNFi or ABT treatment.

Initial decrease in the ambient dose equivalent rate after the Fukushima accident and its difference from Chernobyl

In 2011, after the Fukushima Dai-ichi Nuclear Power Plant accident, the initial decrease in the ambient dose equivalent rate (dH*(10) dt-1), an alternative quantity to the effective dose, was studied using monitoring data obtained from March 16, 2011. The dH*(10) dt-1 was normalized by the 137Cs activity per unit area (norm-dH*(10) dt-1) to analyze the data across monitoring sites with different deposition levels. The norm-dH*(10) dt-1 showed a rapid decrease during the first 60 days, followed by slow decrease and was modeled using two exponential functions. The norm-dH*(10) dt-1 obtained in areas dominated by paved surfaces and buildings showed a faster decrease than the unpaved-dominant field, and this decrease was facilitated in residential areas compared with the evacuation zone. The decrease in norm-dH*(10) dt-1 was compared with simulation results using parameters obtained in Europe after the Chernobyl Nuclear Power Plant accident that represent a decrease due to radionuclide migration (e.g., soil penetration and horizontal wash-off). The simulation results showed a faster decrease than our results, implying that there was less radiocesium migration in Fukushima than in Europe. The results also suggested that the regional variation in the decrease rate led to uncertainty regarding the external dose estimation.

Subjective well-being among rheumatoid arthritis patients

AIM

Subjective well-being (SWB) is a psychological construct that is synonymous with happiness. Many variables including age, sex, income, employment, and marital status are related to SWB. Health is also an important determinant of SWB that can be adversely affected in patients with chronic conditions such as rheumatoid arthritis (RA). In this study, we evaluate the SWB of RA patients and compare it with that of healthy controls.

METHODS

We obtained the original dataset from the "Quality of Life Survey, 2013", which was conducted by the Economic and Social Research Institute, Cabinet Office, Government of Japan. In this survey, SWB was determined by asking participants to rate their happiness between 0 (very unhappy) and 10 (very happy). The survey also included a 56-point questionnaire regarding well-being-related variables. This questionnaire was administered to RA patients recruited from Kobe University Hospital, and clinical and treatment data were simultaneously collected.

RESULTS

Multivariate analysis revealed that RA patients with high or moderate disease activity had SWB scores that were similar to those of controls. However, the SWB scores of RA patients in remission or with low disease activity were higher than those of controls (P = .013). SWB was associated with household income, self-assessment of living costs, self-assessment of health, depression/ anxiety, and social connection.

CONCLUSIONS

For RA patients, achieving the therapeutic target can result in better SWB than that of healthy controls. Financial status, self-assessment of health, psychological stress, and social network are also important determinants for the SWB of RA patients.

Tofacitinib facilitates the expansion of myeloid-derived suppressor cells and ameliorates interstitial lung disease in SKG mice

BACKGROUND

Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is a sometimes life-threatening complication in RA patients. SKG mice develop not only arthritis but also an ILD resembling RA-ILD. We previously reported that tofacitinib, a JAK inhibitor, facilitates the expansion of myeloid-derived suppressor cells (MDSCs) and ameliorates arthritis in SKG mice. The aim of this study was to elucidate the effect of tofacitinib on the ILD in SKG mice.

METHODS

We assessed the effect of tofacitinib on the zymosan (Zym)-induced ILD in SKG mice histologically and examined the cells infiltrating the lung by flow cytometry. The effects of lung MDSCs on T cell proliferation and Th17 cell differentiation were assessed in vitro. We also evaluated the effects of tofacitinib on MDSCs and dendritic cells in vitro.

RESULTS

Tofacitinib significantly suppressed the progression of ILD compared to the control SKG mice. The MDSCs were increased, while Th17 cells, group 1 innate lymphoid cells (ILC1s), and GM-CSF+ILCs were decreased in the lungs of tofacitinib-treated mice. MDSCs isolated from the inflamed lungs suppressed T cell proliferation and Th17 cell differentiation in vitro. Tofacitinib promoted MDSC expansion and suppressed bone marrow-derived dendritic cell (BMDC) differentiation in vitro.

CONCLUSION

Tofacitinib facilitates the expansion of MDSCs in the lung and ameliorates ILD in SKG mice.

Detection of a novel CBFB-MYH11 fusion transcript in acute myeloid leukemia M1 with inv(16)(p13q22)

Acute myeloid leukemia (AML) with an inv(16)(p13q22) or t(16;16)(p13;q22) chromosomal abnormality represents one of the most common subtypes of de novo cases. These chromosomal rearrangements result in multiple CBFB-MYH11 fusion transcripts, with type-A being the most frequent. We here describe a unique case of de novo AML-M1, with inv(16)(p13q22), leading to an unusual CBFB-MYH11 fusion transcript, and der(7)t(7;11)(q31;q21). The fusion transcript involves a CBFB exon 5 with a breakpoint at nucleotide 754, an insertion of a 13-bp sequence of CBFB intron 5 at the fusion point, and the MYH11 exon 27 with a breakpoint at nucleotide 3464. To our knowledge, this CBFB-MYH11 fusion transcript has never been reported previously. The clinical characteristics of the present case are in line with previous reports suggesting that rare CBFB-MYH11 fusion transcripts lead to aberrant characteristics such as an atypical cytomorphology and additional cytogenetic abnormalities.

Additive effects of inhibiting both mTOR and glutamine metabolism on the arthritis in SKG mice

Glutamine metabolism and the mechanistic target of rapamycin (mTOR) pathway are activated cooperatively in the differentiation and activation of inflammatory immune cells. But the combined inhibition of both pathways was rarely investigated. This study investigated how inhibiting both glutamine metabolism with 6-diazo-5-oxo-L-norleucine (DON) and mTOR with rapamycin affects immune cells and the arthritis in a mouse model. We revealed that rapamycin and DON additively suppressed CD4⁺ T cell proliferation, and both of them inhibited Th17 cell differentiation. While DON inhibited the differentiation of dendritic cells and macrophages and facilitated that of Ly6G⁺ granulocytic (G)-MDSCs more strongly than did rapamycin, G-MDSCs treated with rapamycin but not DON suppressed CD4⁺ T cell proliferation in vitro. The combination of rapamycin and DON significantly suppressed the arthritis in SKG mice more strongly than did each monotherapy in vivo. The numbers of CD4⁺ T and Th17 cells in the spleen were lowest in mice treated with the combination therapy. Thus, combined treatment with rapamycin and DON additively ameliorated the arthritis in SKG mice, possibly by suppressing CD4⁺ T cell proliferation and Th17 differentiation. These results suggest the combination of rapamycin and DON may be a potential novel therapy for arthritis.

Cardiac Dysfunction in Duchenne Muscular Dystrophy Is Less Frequent in Patients With Mutations in the Dystrophin Dp116 Coding Region Than in Other Regions

Supplemental Digital Content is available in the text.

Background:

Duchenne muscular dystrophy (DMD), the most common inherited muscular disease in childhood, is caused by dystrophin deficiency because of mutations in the DMD gene. Although DMD is characterized by fatal progressive muscle wasting, cardiomyopathy is the most important nonmuscle symptom threatening the life of patients with DMD. The relationship between cardiac involvement and dystrophin isoforms has not been analyzed.

Methods and Results:

The results of 1109 echocardiograms obtained from 181 Japanese DMD patients with confirmed mutations in the DMD gene were retrospectively analyzed. Patients showed an age-related decline in left ventricular ejection fraction. Patients were divided by patterns of dystrophin isoform deficiency into 5 groups. The cardiac dysfunction-free survival was significantly higher in the group with mutations in the Dp116 coding region than the others, whereas no significant differences in the other 3 groups. At age 25 years, the cardiac dysfunction-free rate was 0.6 in the Dp116 group, but only 0.1 in others. PCR amplification of Dp116 transcript in human cardiac muscle indicated promoter activation.

Conclusions:

Left ventricular ejection fraction in DMD declined stepwise with age. Cardiac dysfunction was less frequent in Dp116-deficient than other patients with DMD. Dp116 transcript was identified in human cardiac muscle for the first time. These results indicate that Dp116 is associated with cardiac involvement in DMD.

Immunometabolism in rheumatoid arthritis

Recent studies have revealed a relationship between cellular metabolism and cell function in immune cells. Cellular metabolism not only provides supplemental ATP, but also supports dynamic changes in cell proliferation and differentiation. For example, T cells exhibit subset-specific metabolic profiles, and require certain types of metabolism for their functions. Determining the metabolic profiles that support inflammatory immune responses may lead to novel treatment strategies for chronic inflammatory diseases such as rheumatoid arthritis (RA). However, the mechanisms by which metabolism modulates cell function have been unclear. Recent studies have begun to unveil unexpected non-metabolic functions for metabolic enzymes in the context of inflammation, including roles in signaling and gene regulation. Here we describe recent findings related to immunometabolism, the metabolome of RA patients, and the metabolically independent functions of glycolytic enzymes. We discuss how metabolic processes impact immune cells, especially T cells and fibroblast like synoviocytes, which are considered the orchestrators of autoimmune arthritis.

Progression of immunoglobulin G4-related disease to systematic lupus erythematosus after gastric cancer surgery: A case report

RATIONALE

Immunoglobulin G4 related disease (IgG4-RD) rarely coexists with other autoimmune diseases, though we had a patient whose primary clinical problem was shifted from IgG4-RD to systemic lupus erythematosus (SLE) after gastrectomy. The present paper aimed to report pathological findings and clinical course of the patient.

PATIENT CONCERNS

The patient was a male aged 74 years old with gastric cancer characterized by the following symptoms: Raynaud phenomenon, polyarthralgia, and swollen parotid glands on both sides. Before gastrectomy, laboratory examination results showed renal dysfunction, hypocomplementemia, antinuclear antibodies (ANAs) positivity, and elevated serum IgG and IgG4 levels.

DIAGNOSIS

Based on postoperative renal biopsy showing severe plasma cell infiltration with tubulointerstitial fibrosclerosis, the patient was diagnosed with IgG4-RD. Despite significant improvement in renal function and reduction in parotid gland swelling during the postoperative follow-up period, after 7 months of the gastrectomy, anti-DNA antibody levels were increased and serositis was detected, which indicated the onset of SLE. IgG4-type ANA were also detected in the sera of the patient.

INTERVENTIONS

Treatment by oral prednisolone at 30 mg/day was initiated.

OUTCOMES

Pericardial fluid, pleural effusions, and thickening of the gallbladder wall improved after 3 months of treatment according to computed tomography.

LESSONS

This study presented a rare case of comorbidity, wherein the patient's primary problem progressed from IgG4-type ANA-positive IgG4-RD to SLE after excision of gastric cancer.

S100A12 facilitates osteoclast differentiation from human monocytes

Osteoclasts play a critical role not only in bone homeostasis but also in inflammatory osteolysis, such as that occurring in inflammatory arthritis and systemic inflammation. In both inflammation conditions, inflammatory cytokines like Interleukin (IL)-1, IL-6 and tumor necrosis factor (TNF)-α induce RANKL expression in osteoblasts, but the roles of these cytokines in osteoclast activation remain unclear. S100A12, an S100 family member, is a low-molecular-weight calcium-binding protein. Although it has a pro-inflammatory role, its effects on osteoclast differentiation have been unclear. Here we examined the direct effects of S100A12 on human osteoclasts in vitro. S100A12 facilitated osteoclast formation in the presence of RANKL, as judged by the cells’ morphology and elevated expression of osteoclast-related molecules, including NFATc1, ACP5, CALCR, and ITGβ3. In addition, S100A12 administration markedly enhanced the osteoclasts’ bone resorption ability, consistent with their increased expression levels of CTSK and CA2. Blocking RAGE and TLR4 cancelled the effects of S100A12. Our results indicate that S100A12 is a potential therapeutic target for inflammatory osteolysis.

Myeloid-derived suppressor cells in non-neoplastic inflamed organs

BACKGROUND

Myeloid-derived suppressor cells (MDSCs) are a highly heterogeneous population of immature myeloid cells with immunosuppressive function. Although their function in tumor-bearing conditions is well studied, less is known about the role of MDSCs in various organs under non-neoplastic inflammatory conditions.

MAIN BODY

MDSCs are divided into two subpopulations, G-MDSCs and M-MDSCs, and their distribution varies between organs. MDSCs negatively control inflammation in inflamed organs such as the lungs, joints, liver, kidneys, intestines, central nervous system (CNS), and eyes by suppressing T cells and myeloid cells. MDSCs also regulate fibrosis in the lungs, liver, and kidneys and help repair CNS injuries. MDSCs in organs are plastic and can differentiate into osteoclasts and tolerogenic dendritic cells according to the microenvironment under non-neoplastic inflammatory conditions.

CONCLUSION

This article summarizes recent findings about MDSCs under inflammatory conditions, especially with respect to their function and differentiation in specific organs.

Successful treatment with tacrolimus in TAFRO syndrome: two case reports and literature review

RATIONALE

TAFRO syndrome is a systemic inflammatory disorder characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis, renal dysfunction, and organomegaly. In contrast to that in multicentric Castleman disease, interleukin-6 targeting strategies seem ineffective in some TAFRO syndrome cases; however, the optimal treatment remains unclear. Here, we report 2 cases of TAFRO syndrome, where 1 with cardiomyopathy, successfully treated with tacrolimus. This is the first case report of successful treatment with tacrolimus in TAFRO syndrome.

PATIENT CONCERNS

Both patients (cases 1 and 2) developed fever, anasarca, thrombocytopenia, renal dysfunction, and mild hepatosplenomegaly.

DIAGNOSES

In both patients, lymph node pathology revealed mixed type Castleman disease-like features, and bone marrow showed reticulin myelofibrosis. TAFRO syndrome was diagnosed based on the patients' laboratory, clinical, and pathologic findings. In case 2, we observed a rare complication of cardiomyopathy with no evidence of takotsubo cardiomyopathy or viral myocarditis.

INTERVENTIONS AND OUTCOMES

In case 1, tocilizumab combined with glucocorticoids was ineffective and caused septic shock; additionally, cyclosporine A was discontinued because of hepatotoxicity. However, tacrolimus was effective in resolving TAFRO syndrome without any adverse events. In case 2, tacrolimus completely reversed TAFRO syndrome and was also effective in cardiomyopathy.

LESSONS

This report suggests that tacrolimus is potentially effective and safe as an initial treatment and a glucocorticoid-sparing agent. Our literature review shows that calcineurin inhibitors, including tacrolimus, may be effective in TAFRO syndrome. Since previous studies indicate a role of Th1 inflammation in TAFRO syndrome pathogenesis, tacrolimus may, therefore, be effective in treating TAFRO syndrome.

ETV6-ABL1 fusion combined with monosomy 7 in childhood B-precursor acute lymphoblastic leukemia

ETV6-ABL1 fusion is a rare but recurrent oncogenic lesion found in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL), without an established chromosomal abnormality, and is associated with poor outcome. In ETV6-ABL1-positive cases, an in-frame fusion produced by a complex rearrangement results in constitutive chimeric tyrosine kinase activity. Monosomy 7 is also a rare and unfavorable chromosomal abnormality in childhood BCP-ALL. Here, we report a 14-year-old female BCP-ALL patient with ETV6-ABL1 fusion combined with monosomy 7. She was admitted to our hospital because of persistent fever. Bone marrow nuclear cell count on admission was 855,000/µL with 90.0% blastic cells of lymphoid morphology. Blasts were positive for CD10, CD19, CD20, CD34, cyCD79a, cyTdT, HLA-DR, and CD66c, had a karyotype of 45, XX, - 7 [18/20] and a split signal for ABL1 FISH probe (92.7%), and were sensitive to tyrosine kinase inhibitors, imatinib and dasatinib, in vitro. ETV6-ABL1 fusion transcript was identified by whole transcriptome sequencing and confirmed by RT-PCR. She was treated with the high-risk protocol based on ALL-BFM 95, achieved complete remission (CR) after induction chemotherapy, and maintained CR for 4 months. To our knowledge, this is the first report of ETV6-ABL1 fusion combined with monosomy 7 in childhood BCP-ALL.

Juvenile migration of the exclusively pelagic cyprinid, Gnathopogon caerulescens (Honmoroko) in Lake Biwa, Central Japan

Migration of wild and cultivated juvenile honmoroko Gnathopogon caerulescens of from the spawning and nursery areas in Lake Biwa were investigated, both in the Ibanaiko Lagoon and its outlet to Daido River, using beam-trawl surveys in 2013 and 2014. The study demonstrated migration of G. caerulescens from a nursery lagoon toward Lake Biwa after the juvenile stage. These findings appear to be the first direct evidence for migration of an exclusively pelagic cyprinid species from a littoral nursery to a pelagic adult habitat in a large deep lake.

Claviform aspergillus-related vegetation in the left ventricle of a patient with systemic lupus erythematosus

A 38-year-old woman was diagnosed with systemic lupus erythematosus and received immunosuppressive therapy. After 6 months of treatment, workup for low-grade fever yielded elevated enzyme-linked immunosorbent assay titers for Aspergillus antigen in serum and ascites, leading to the diagnosis of disseminated aspergillosis. Transthoracic echocardiography revealed a claviform vegetation attached to the left ventricular anterior septum. Two days after the start of antifungal Amphotericin-B therapy, the patient suffered from several neurologic disorders. A second transthoracic echocardiography revealed that the vegetation decreased in size. Two weeks later, the vegetation increased again. Combination therapy of Amphotericin-B and Voriconazole was initiated, and the vegetation eventually disappeared completely. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:231-232, 2018.

Determination of the antimicrobial susceptibility and molecular profile of clarithromycin resistance in the Mycobacterium abscessus complex in Japan by variable number tandem repeat analysis

Mycobacterium abscessus complex, including three subspecies-M. abscessus, M. massiliense, and M. bolletii-is resistant to a variety of antibiotics so limited treatment options are available. The susceptibility of these subspecies to antimicrobial agents depends in particular on the erm(41) sequevar and rrl mutations in the 23S rRNA, which are potentially related to clarithromycin (CLR) resistance. The purpose of this study was to carry out identification and molecular characterization of these subspecies based on variable number of tandem repeats (VNTR) analysis. Twenty-four M. abscessus complex strains were identified as M. abscessus and M. massiliense and these subspecies could be discriminated between based on their resistance to CLR, as determined by truncation or mutation of erm(41) or mutation of rrl, as illustrated by their VNTR patterns. In conclusion, we confirmed that the CLR susceptibility profiles could be differentiated according to the subspecies of M. abscessus complex strains by their VNTR patterns.