Systematic review and meta-analysis for the 2024 update of the Japan College of Rheumatology clinical practice guidelines for the management of rheumatoid arthritis.

OBJECTIVES: To update evidence on the efficacy and safety of disease-modifying antirheumatic drugs (DMARDs) and provide information to the taskforce for the 2024 update of the Japan College of Rheumatology (JCR) clinical practice guidelines (CPG) for the management of rheumatoid arthritis (RA). METHODS: We searched various databases for randomised controlled trials on RA published until June 2022, with no language restriction. For each of the 15 clinical questions, 2 independent reviewers screened the articles, evaluated the core outcomes, and performed meta-analyses. RESULTS: Subcutaneous injection of methotrexate (MTX) showed similar efficacy to oral MTX in MTX-naïve RA patients. Ozoralizumab combined with MTX improved drug efficacy compared to the placebo in RA patients with inadequate response (IR) to csDMARD. Rituximab with and without concomitant csDMARDs showed similar efficacy to other bDMARDs in bDMARD-IR RA patients. Combined Janus kinase inhibitors and MTX achieved similar clinical responses and equal safety during a 4-year period compared to tumour necrosis factor inhibitors in MTX-IR RA patients. Biosimilars showed efficacy equivalent to that of the original bDMARDs in csDMARD-IR and bDMARD-IR RA patients. CONCLUSION: This systematic review provides latest evidence for the 2024 update of the JCR CPG for RA management.

Comprehensive lipidomics of lupus-prone mice using LC-MS/MS identifies the reduction of palmitoylethanolamide that suppresses TLR9-mediated inflammation.

Lipid mediators are known to play crucial roles not only in the onset of the inflammatory response but also in the induction of resolution of inflammation. Here, we report that palmitoylethanolamide (PEA), an endogenous N-acylethanolamine, can suppress the inflammation induced by Toll-like receptor (TLR) signaling both in vitro and in vivo. PEA was found to be significantly reduced in the serum and spleen of lupus-prone MRL/lpr mice analyzed by lipidomics. PEA suppressed pro-inflammatory cytokine production in a mouse macrophage cell line stimulated with TLR ligands such as lipopolysaccharide, peptidoglycan, poly (I:C), imiquimod, and CpG-ODN. PEA also inhibited both mRNA and protein levels of IL-6 in bone marrow-derived dendritic cells (BMDCs) and B cells stimulated with CpG-ODN. Augmentation of cell surface CD86 and CD40 on BMDCs and B cells, IgM production, and cell proliferation of B cells in response to CpG-ODN were attenuated by PEA. Moreover, PEA treatment significantly reduced mortality and serum IL-6 levels in mice injected with CpG-ODN plus D-galactosamine. Taken together, PEA ameliorates inflammation induced by TLR signaling, which could be a novel therapeutic target for inflammatory disorders.

l-Leucine influx through Slc7a5 regulates inflammatory responses of human B cells via mammalian target of rapamycin complex 1 signaling.

Objectives: Increasing evidence has revealed the close correlation between immune cell functions and their intracellular metabolism. Mammalian target of rapamycin complex 1 (mTORC1) is the important metabolism-modulating signal that regulates cellular activities. In certain types of cell, it is known that mTORC1 activation depends on influx of l-leucine through an amino acid transporter, Slc7a5. In B cells, however, the expression and the role of Slc7a5 have never been investigated. Methods: CD19+ B cells were obtained from peripheral blood of healthy adults and stimulated by a toll-like receptor 9 ligand, CpG oligodeoxynucleotides. The expression of Slc7a5 and l-leucine uptake were evaluated by RT-PCR, flow cytometry and radioisotope assay. Then the effect of Slc7a5 inhibition on mTORC1 activity, plasmablast differentiation and production of IgG and inflammatory cytokines were analyzed. Results: CpG stimulation significantly induced the expression of Slc7a5 in B cells, resulting in l-leucine influx. Furthermore, inhibition of Slc7a5 abrogated mTORC1 activation, plasmablast differentiation, and production of IgG and inflammatory cytokines in CpG-stimulated B cells. Conclusion: l-leucine influx through Slc7a5 critically regulates mTORC1 activity and the immunological responses of human B cells. Slc7a5-mTORC1 pathway may provide a novel therapeutic strategy for autoimmune diseases.

Large-vessel involvement in granulomatosis with polyangiitis successfully treated with rituximab: A case report and literature review.

Granulomatosis with polyangiitis (GPA) is primary necrotizing vasculitis, which predominantly affects small to medium vessels. Herein, we describe a case of a 60-year-old female with GPA who developed inflammatory wall thickening localized in the aortic arch, upper abdominal aorta, and pulmonary artery. The wall thickening in the large vessels and other GPA lesions such as lung nodules and orbital mass had failed to respond to high-dose glucocorticoids combined with cyclophosphamide; however, all were successfully treated with rituximab. Our literature review identified 24 cases of large-vessel involvement associated with GPA. Luminal stenosis, occlusion, or wall thickening were observed in 8, periaortitis in 11, and aneurysms in 5 cases. The most commonly affected vessel was the abdominal aorta (12 cases), followed by the thoracic aorta (6 cases), subclavian artery (4 cases), and internal carotid artery (4 cases). Glucocorticoids were used in 23 cases, 20 of which received combination therapy with cyclophosphamide. Surgical or endovascular therapies were performed in 10 cases with aneurysmal dilatation. This is the first case showing the potential efficacy of rituximab for refractory large-vessel involvement associated with GPA.

Successful leukocytapheresis therapy in a patient with rheumatoid arthritis on maintenance hemodialysis.

We report the case of a 44-year-old female undergoing maintenance hemodialysis in whom early-phase rheumatoid arthritis (RA) was successfully treated by leukocytapheresis (LCAP). The effects of prednisone, tacrolimus, and etanercept were limited, but LCAP was highly effective and its efficacy continued even after cessation of LCAP. Moreover, remission was maintained for 2 years after discontinuation of medication. LCAP may be an important treatment option for RA patients with end-stage renal failure who are on hemodialysis.

Effects of tofacitinib on lymphocytes in rheumatoid arthritis: relation to efficacy and infectious adverse events.

OBJECTIVES: To assess the effects of tofacitinib on T lymphocytes in RA patients with a special focus on efficacy and infectious adverse events (iAEs). METHODS: Forty-four RA patients participated in 12-month phase II/III randomized clinical trials and an open-label extension trial. Peripheral lymphocyte subsets and in vitro CD4(+) T lymphocyte proliferation were measured in 23 patients of 44 at baseline and at the end of the 12-month trial. RESULTS: Forty-four patients [35 females, age 54.3 years, disease duration 84.3 months, simplified disease activity index (SDAI) 36.5, CRP 24.9 mg/l, ESR 53 mm/h, MMP-3 284 pg/ml, RF 172.6 IU/ml, neutrophil count 4842 per µl, lymphocyte count 1410 per µl] were treated with tofacitinib. At the end of the study, the SDAI improved to 6.2, but the peripheral lymphocyte count and absolute numbers of CD4(+) and CD8(+) subpopulations did not change during this period. However, CD4(+) T lymphocyte proliferation was suppressed, which correlated with the improvement in SDAI, but not with iAEs (n = 19) during the 12-month treatment. Receiver operating characteristic analysis identified a CD8(+) T lymphocyte count ≤ 211 per µl at baseline as a significant predictor of clinically significant iAEs. CONCLUSION: The efficacy of tofacitinib is mediated through the suppression of CD4(+) T lymphocyte proliferation without affecting the absolute number of these cells in the periphery. A low CD8(+) T cell count at baseline correlated with the development of iAEs during the treatment of RA patients.

Herpes zoster in the context of immune reconstitution inflammatory syndrome in patients with rheumatic diseases: a single-center retrospective study.

Immune reconstitution inflammatory syndrome (IRIS) experienced in rheumatology practice is diverse and includes opportunistic infections such as herpes zoster (HZ). This study aimed to explore the risk of HZ in patients with rheumatic diseases in the perspective of IRIS. The study retrospectively reviewed the clinical courses of 20 patients with HZ and investigated the IRIS triggers such as the reduction or discontinuation of immunosuppressive drugs within 3 months and coronavirus disease 2019 (COVID-19) vaccination within 4 weeks prior to HZ development. Disease activity of the underlying rheumatic disease at HZ onset was evaluated using the physician's global assessment. Thirteen patients developed HZ after reducing or discontinuing immunosuppressive drugs, with mild and stable disease activity. In four of these cases, disease activity increased after dose reduction or discontinuation, and HZ subsequently developed. Two of the seven patients who did not reduce or discontinue immunosuppressive drugs received the COVID-19 vaccination. Fifteen patients (75%) had at least one of the two IRIS triggers. Four of the five patients who developed HZ without any IRIS triggers were at HZ risk. To conclude, IRIS, caused by the reduction or discontinuation of immunosuppressive drugs, may be involved in the development of HZ in rheumatology practice.

The JAK inhibitor tofacitinib regulates synovitis through inhibition of interferon-γ and interleukin-17 production by human CD4+ T cells.

OBJECTIVE: Tofacitinib (CP-690,550) is a novel JAK inhibitor that is currently in clinical trials for the treatment of rheumatoid arthritis (RA). The aim of this study was to examine the effects of tofacitinib in vitro and in vivo in RA, in order to elucidate the role of JAK in the disease process. METHODS: CD4+ T cells, CD14+ monocytes, and synovial fibroblasts (SFs) were purified from the synovium and peripheral blood of patients with RA and were evaluated for the effect of tofacitinib on cytokine production and cell proliferation. For in vivo analysis, synovium and cartilage samples obtained from patients with RA were implanted in immunodeficient mice (SCID-HuRAg mice), and tofacitinib was administered via an osmotic minipump. RESULTS: Tofacitinib treatment of CD4+ T cells originating from synovium and peripheral blood inhibited the production of interleukin-17 (IL-17) and interferon-γ (IFNγ) in a dose-dependent manner, affecting both proliferation and transcription, but had no effect on IL-6 and IL-8 production. Tofacitinib did not affect IL-6 and IL-8 production by RASFs and CD14+ monocytes. However, conditioned medium from CD4+ T cells cultured with tofacitinib inhibited IL-6 production by RASFs and IL-8 production by CD14+ monocytes. Treatment of SCID-HuRAg mice with tofacitinib decreased serum levels of human IL-6 and IL-8 and markedly suppressed invasion of synovial tissue into cartilage. CONCLUSION: Tofacitinib directly suppressed the production of IL-17 and IFNγ and the proliferation of CD4+ T cells, resulting in inhibition of IL-6 production by RASFs and IL-8 production by CD14+ cells and decreased cartilage destruction. In CD4+ T cells, presumably Th1 and Th17 cells, JAK plays a crucial role in RA synovitis.

Human mesenchymal stem cells inhibit osteoclastogenesis through osteoprotegerin production.

OBJECTIVE: Mesenchymal stem cells (MSCs) have been proposed to be a useful tool for treatment of rheumatoid arthritis (RA), not only because of their multipotency but also because of their immunosuppressive effect on lymphocytes, dendritic cells, and other proinflammatory cells. Since bone destruction caused by activated osteoclasts occurs in RA, we undertook the present study to investigate the effect of MSCs on osteoclast function and differentiation in order to evaluate their potential use in RA therapy. METHODS: Human MSCs and peripheral blood mononuclear cells were cultured under cell-cell contact-free conditions with osteoclast induction medium. Differentiation into osteoclast-like cells was determined by tartrate-resistant acid phosphatase staining and expression of osteoclast differentiation markers. RESULTS: The number of osteoclast-like cells was decreased and expression of cathepsin K and nuclear factor of activated T cells c1 (NF-ATc1) was down-regulated by the addition of either MSCs or a conditioned medium obtained from MSCs. Osteoprotegerin (OPG) was constitutively produced by MSCs and inhibited osteoclastogenesis. However, osteoclast differentiation was not fully recovered upon treatment with either anti-OPG antibody or OPG small interfering RNA, suggesting that OPG had only a partial role in the inhibitory effect of MSCs. Moreover, bone-resorbing activity of osteoclast-like cells was partially recovered by addition of anti-OPG antibody into the conditioned medium. CONCLUSION: The present results indicate that human MSCs constitutively produce OPG, resulting in inhibition of osteoclastogenesis and expression of NF-ATc1 and cathepsin K in the absence of cell-cell contact. Therefore, we conclude that human MSCs exert a suppressive effect on osteoclastogenesis, which may be beneficial in inhibition of joint damage in RA.

Adult-onset Still's disease with macrophage activation syndrome successfully treated with a combination of methotrexate and etanercept.

We report a 16-year-old female case of intractable adult-onset Still's disease accompanied by macrophage activation syndrome, who went into full remission after switching from infliximab to etanercept. Although the disease promptly relapsed when etanercept was discontinued, she again responded fully upon the reintroduction of etanercept. Furthermore, the effect of etanercept was apparently enhanced by combining it with a sufficient dose of methotrexate. This combination therapy should be considered as one of treatment options for the disease.

Factors Influencing Plasma Coproporphyrin-I Concentration as Biomarker of OATP1B Activity in Patients With Rheumatoid Arthritis.

Organic anion transporting polypeptides (OATPs) 1B are drug transporters mainly expressed in the sinusoidal membrane. In previous reports, genetic factor, 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), which is one of the uremic toxins, inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) decreased OATP1B1 activity in vitro, but in vivo effects of these factors have not been elucidated. Plasma coproporphyrin-I (CP-I) is spotlighted as a highly accurate endogenous substrate of OATP1B. This study focused on patients with rheumatoid arthritis (RA) and evaluated the influence of several factors comprising gene polymorphisms, uremic toxins, and inflammatory cytokines on OATP1B activity using plasma CP-I concentration. Thirty-seven outpatients with RA who satisfied the selection criteria were analyzed at the time of recruitment (baseline) and at the next visit. OATP1B1*15 carriers tended to have higher CP-I concentration compared with noncarriers. Plasma CP-I correlated positively with CMPF concentration, but did not correlate with IL-6 or TNF-α concentration. Multiple logistic regression analysis by stepwise selection identified plasma CMPF concentration and OATP1B1*15 allele as significant factors independently affecting plasma CP-I concentration at baseline and at the next visit, respectively. In conclusion, the present results suggest that inflammatory cytokines do not have clinically significant effects on OATP1B activity, whereas the effects of genetic polymorphisms and uremic toxins should be considered.

Effectiveness of subcutaneous tocilizumab in refractory adult Still's disease: report of three cases and a review of the literature.

Adult Still's disease (ASD) is a systemic inflammatory disorder characterised by spiking fever, skin rash, arthritis, hepatosplenomegaly, and elevated inflammatory markers. Several proinflammatory cytokines, including interleukin (IL)-6, contribute to its pathogenesis. There have been some recent reports on the efficacy of tocilizumab (TCZ), a humanised anti-IL-6 receptor antibody, in the treatment of ASD refractory to conventional therapy. However, most of the evidence is for intravenous administration of TCZ, whereas subcutaneous injection is often preferred in terms of efficiency in cost and labour. We have experienced three patients whose ASD was refractory to corticosteroid and immunosuppressant therapy but showed a marked response to off-label use of subcutaneous TCZ (TCZ-SC). Patient 1 received TCZ-SC 162 mg on days 0 and 14 and every week thereafter. Patients 2 and 3 received TCZ-SC every 2 weeks. At the time of initiation of TCZ-SC, all three patients had elevated inflammatory markers and two had fever despite previous therapy. After the first TCZ-SC injection, the patients became afebrile within one day and inflammatory parameters (i.e. C-reactive protein and erythrocyte sedimentation rate) returned to normal within 2 weeks. None of the patients developed severe infection or other serious side effects during 104 weeks of follow-up. There have been only a limited number of case reports showing that TCZ-SC significantly improves refractory ASD during its active phase. Our experience with these patients suggests that TCZ-SC could, as well as offering cost efficiency in clinical practice, be a potent treatment option for refractory ASD.

Comprehensive epigenetic landscape of rheumatoid arthritis fibroblast-like synoviocytes.

Epigenetics contributes to the pathogenesis of immune-mediated diseases like rheumatoid arthritis (RA). Here we show the first comprehensive epigenomic characterization of RA fibroblast-like synoviocytes (FLS), including histone modifications (H3K27ac, H3K4me1, H3K4me3, H3K36me3, H3K27me3, and H3K9me3), open chromatin, RNA expression and whole-genome DNA methylation. To address complex multidimensional relationship and reveal epigenetic regulation of RA, we perform integrative analyses using a novel unbiased method to identify genomic regions with similar profiles. Epigenomically similar regions exist in RA cells and are associated with active enhancers and promoters and specific transcription factor binding motifs. Differentially marked genes are enriched for immunological and unexpected pathways, with "Huntington's Disease Signaling" identified as particularly prominent. We validate the relevance of this pathway to RA by showing that Huntingtin-interacting protein-1 regulates FLS invasion into matrix. This work establishes a high-resolution epigenomic landscape of RA and demonstrates the potential for integrative analyses to identify unanticipated therapeutic targets.

Preparation and characterization of carbonic anhydrase-conjugated liposomes for catalytic synthesis of calcium carbonate particles.

The biomimetic approach using immobilized enzymes is useful for the synthesis of structurally defined inorganic materials. In this work, carbonic anhydrase (CA) from bovine erythrocytes was covalently conjugated at 25°C to the liposomes composed of 15mol% 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine-N-(glutaryl) (NG-POPE), and the zwitterionic and anionic phospholipids with the same acyl chains as NG-POPE. For the conjugation, the carboxyl groups of liposomal NG-POPE were activated with 11mM 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and 4.6mM N-hydroxysulfosuccinimide (sulfo-NHS). The carbonic anhydrase-conjugated liposomes (CALs) with the mean hydrodynamic diameter of 149nm showed the esterase activity corresponding to on average 5.5×102 free CA molecules per liposome. On the other hand, the intrinsic fluorescence and absorbance measurements consistently revealed that on average 1.4×103 CA molecules were conjugated to a liposome, suggesting that the molecular orientation of enzyme affected its activity. The formation of calcium carbonate particles was significantly accelerated by the CALs ([lipid]=50µ M) in the 0.3M Tris solution at 10-40°C with dissolved CO2 (≈17mM) and CaCl2 (46mM). The anionic CALs were adsorbed with calcium as revealed with the ζ-potential measurements. The CAL system offered the calcium-rich colloidal interface where the bicarbonate ions were catalytically produced by the liposome-conjugated CA molecules. The CALs also functioned in the external loop airlift bubble column operated with a model flue gas (10vol/vo% CO2), yielding partly agglomerated calcium carbonate particles as observed with the scanning electron microscopy (SEM).

LBH Gene Transcription Regulation by the Interplay of an Enhancer Risk Allele and DNA Methylation in Rheumatoid Arthritis.

OBJECTIVE: To identify nonobvious therapeutic targets for rheumatoid arthritis (RA), we performed an integrative analysis incorporating multiple "omics" data and the Encyclopedia of DNA Elements (ENCODE) database for potential regulatory regions. This analysis identified the limb bud and heart development (LBH) gene, which has risk alleles associated with RA/celiac disease and lupus, and can regulate cell proliferation in RA. We identified a novel LBH transcription enhancer with an RA risk allele (rs906868 G [Ref]/T) 6 kb upstream of the LBH gene with a differentially methylated locus. The confluence of 3 regulatory elements, rs906868, an RA differentially methylated locus, and a putative enhancer, led us to investigate their effects on LBH regulation in fibroblast-like synoviocytes (FLS). METHODS: We cloned the 1.4-kb putative enhancer with either the rs906868 Ref allele or single-nucleotide polymorphism (SNP) variant into reporter constructs. The constructs were methylated in vitro and transfected into cultured FLS by nucleofection. RESULTS: We found that both variants increased transcription, thereby confirming the region's enhancer function. Unexpectedly, the transcriptional activity of the Ref risk allele was significantly lower than that of the SNP variant and is consistent with low LBH levels as a risk factor for aggressive FLS behavior. Using RA FLS lines with a homozygous Ref or SNP allele, we confirmed that homozygous Ref lines expressed lower LBH messenger RNA levels than did the SNP lines. Methylation significantly reduced enhancer activity for both alleles, indicating that enhancer function is dependent on its methylation status. CONCLUSION: This study shows how the interplay between genetics and epigenetics can affect expression of LBH in RA.

Familial Mediterranean Fever with Rheumatoid Arthritis Complicated by Pulmonary Paragonimiasis.

A 42-year-old woman presented with an intermittent fever and chest and back pain, and an abnormal chest shadow was detected. She was diagnosed with paragonimiasis caused by Paragonimus westermani. Praziquantel therapy improved the abnormal chest shadow, but did not relieve her symptoms. She was also diagnosed with familial Mediterranean fever (FMF), and colchicine therapy resolved her symptoms. She subsequently developed arthralgia and morning stiffness in her hands. We also diagnosed the patient with rheumatoid arthritis (RA), and corticosteroid and salazosulfapyridine therapy improved her symptoms. The existence of paragonimiasis complicated the diagnosis of FMF. The coexistence of FMF and RA is very rare, but does exist.

Abnormal PTPN11 enhancer methylation promotes rheumatoid arthritis fibroblast-like synoviocyte aggressiveness and joint inflammation.

The PTPN11 gene, encoding the tyrosine phosphatase SHP-2, is overexpressed in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) compared with osteoarthritis (OA) FLS and promotes RA FLS invasiveness. Here, we explored the molecular basis for PTPN11 overexpression in RA FLS and the role of SHP-2 in RA pathogenesis. Using computational methods, we identified a putative enhancer in PTPN11 intron 1, which contained a glucocorticoid receptor- binding (GR-binding) motif. This region displayed enhancer function in RA FLS and contained 2 hypermethylation sites in RA compared with OA FLS. RA FLS stimulation with the glucocorticoid dexamethasone induced GR binding to the enhancer and PTPN11 expression. Glucocorticoid responsiveness of PTPN11 was significantly higher in RA FLS than OA FLS and required the differentially methylated CpGs for full enhancer function. SHP-2 expression was enriched in the RA synovial lining, and heterozygous Ptpn11 deletion in radioresistant or innate immune cells attenuated K/BxN serum transfer arthritis in mice. Treatment with SHP-2 inhibitor 11a-1 reduced RA FLS migration and responsiveness to TNF and IL-1ß stimulation and reduced arthritis severity in mice. Our findings demonstrate how abnormal epigenetic regulation of a pathogenic gene determines FLS behavior and demonstrate that targeting SHP-2 or the SHP-2 pathway could be a therapeutic strategy for RA.