Takashi Igawa

M1 and M2 Monocytes in Rheumatoid Arthritis: A Contribution of Imbalance of M1/M2 Monocytes to Osteoclastogenesis

Objectives We investigated the relationships among M1 monocytes, M2 monocytes, osteoclast (OC) differentiation ability, and clinical characteristics in patients with rheumatoid arthritis (RA). Methods Peripheral blood mononuclear cells (PBMCs) were isolated from RA patients and healthy donors, and we then investigated the number of M1 monocytes or M2 monocytes by fluorescence-activated cell sorting. We also obtained and cultured CD14-positive cells from PBMCs from RA patients and healthy donors to investigate OC differentiation in vitro. Results Forty RA patients and 20 healthy donors were included. Twenty-two patients (55%) were anticitrullinated protein antibody (ACPA) positive. The median M1/M2 ratio was 0.59 (0.31–1.11, interquartile range). There were no significant differences between the RA patients and healthy donors. There was a positive correlation between the M1/M2 ratio and the differentiated OC number in vitro in RA patients (ρu2009=u20090.81, pu2009<u20090.001). The ACPA-positive patients had significantly higher M1/M2 ratios in vivo (pu2009=u20090.028) and significantly greater numbers of OCs in vitro (pu2009=u20090.005) than the ACPA-negative patients. Multivariable regression analysis revealed that the M1/M2 ratio was the sole significant contribution factor to in vitro osteoclastogenesis. RA patients with M1/M2 ratios >1 (having relatively more M1 monocytes) had higher C-reactive protein and erythrocyte sedimentation rates than RA patients with M1/M2 ratios ≤1. M1-dominant monocytes in vitro produced higher concentrations of interleukin-6 upon stimulation with lipopolysaccharide than M2 monocytes. Conclusion M1/M2 monocytes imbalance strongly contributes to osteoclastogenesis of RA patients. Our findings cast M1 and M2 monocyte subsets in a new light as a new target of treatments for RA to prevent progression of osteoclastic bone destruction.

CD4+ CD52lo T-cell expression contributes to the development of systemic lupus erythematosus

The cell-surface glycoprotein CD52 is widely expressed in lymphocytes. CD4+CD52hi T cells are functioning suppressor CD4+T cells. We investigated the role of the immune regulation of CD4+CD52 T cells in systemic lupus erythematosus (SLE). CD4+CD52lo T cells were increased in SLE patients, in positive correlation with SLEDAI, anti-ds-DNA antibody, and IgG concentration. Circulating follicular helper-like T cells (Tfh-like cells) were also increased in SLE, in positive correlation with CD4+CD52lo T cells. Chemokine receptor 8 (CCR8) expression in CD4+CD52lo T cells was increased. In vitro experiments using CD4 T cells of SLE patients showed that thymus and activation-regulated chemokine (TARC), a ligand of CCR8, contributed to the development of CD4+CD52hi T cells into CD4+CD52lo T cells. Our findings suggest that CD4+CD52lo T-cell upregulation is involved in the production of pathogens by autoantibodies, and TARC may contribute to the development of SLE through an aberrant induction of CD4+CD52lo T cells.

Scleroderma Renal Crisis Complicated with Thrombotic Microangiopathy Triggered by Influenza B Virus Infection

A 44-year-old Japanese man with a 14-year history of limited cutaneous systemic sclerosis (SSc) was admitted with a fever, hypertension, anemia, thrombocytopenia, and renal dysfunction. On admission, hypertension, hyperreninemia, acute renal dysfunction, hemolytic anemia, and thrombocytopenia led to the diagnosis of scleroderma renal crisis (SRC) complicated with thrombotic microangiopathy (TMA). The patient had also been infected with influenza B virus almost six days before admission. Following treatment with plasma exchange, an angiotensin-converting enzyme inhibitor, and an anti-virus agent, his general condition improved. He had no risk factors for SRC. In SSc patients, an influenza virus infection might trigger SRC complicated with TMA.

Denosumab is effective toward glucocorticoid-induced osteoporosis patients complicated with rheumatic diseases regardless of prior anti-osteoporotic drugs

We examined the efficacy and safety of denosumab as treatment for glucocorticoid-induced osteoporosis (GIOP) patients complicated with rheumatic diseases, by measuring patients’ lumber bone mineral density (BMD) and bone turnover markers. A total of 66 consecutive patients for whom denosumab was initiated between July 2013 and August 2016 were enrolled and evaluated for 12xa0months. All of the patients were treated with glucocorticoids for underlying rheumatic diseases. The clinical assessment included measurements of the BMD of the lumbar spine (L2–L4) by a dual-energy X-ray absorptiometry technique and the bone turnover markers N-terminal telopeptide of type 1 collagen (NTX) in urine, serum intact procollagen type 1xa0N-terminal propeptide (P1NP), and bone-specific alkaline phosphatase (BAP) at baseline, 6xa0months and 12xa0months after the start of denosumab treatment. Adverse events (AEs) until 12xa0months were also analyzed. The mean percentage changes in BMD from baseline to 6 and 12xa0months were significant (2.85% increase, pu2009<u20090.0001 and 4.40% increase, pu2009<u20090.0001, respectively) regardless of the prior anti-osteoporotic drugs treatment (16 no transition from anti-osteoporotic drugs, 27 transition from bisphosphonate, 23 transition from teriparatide). The decreases in NTX, P1NP and BAP at 6 and 12xa0months were also significant. No serious AEs were noted. A multivariable logistic analysis showed that the prednisolone dose at baseline was associated with the clinical response to denosumab. In a real-world setting, denosumab was effective and safe for treating GIOP patients complicated with rheumatic diseases regardless of prior anti-osteoporotic drug treatment.

Rituximab-induced Acute Thrombocytopenia in Granulomatosis with Polyangiitis

A 72-year-old Japanese woman diagnosed with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis was admitted to our hospital with hearing loss, temporal pain, and sudden blindness. We finally diagnosed recurrent granulomatosis with polyangiitis and initiated methyl-prednisolone pulse therapy (1,000 mg) followed by prednisolone (30 mg/day) and rituximab (RTX). After the third RTX administration, she developed bloody stools along with acute thrombocytopenia and low complement levels. We diagnosed rituximab-induced acute thrombocytopenia (RIAT), and her platelet counts spontaneously recovered. This case suggests that after RTX therapy RIAT may sometimes cause severe thrombocytopenia, and that monitoring the complements may be useful for making an early diagnosis of RIAT.

Reversible Cognitive Dysfunction in Elderly-onset Systemic Lupus Erythematosus, Successfully Treated with Aggressive Immunosuppressive Therapy

A 70-year-old Japanese woman presented to our hospital with gait disturbance and cognitive dysfunction. Since she had arthritis, lymphopenia, hypocomplementemia, and anti-nuclear and anti-double-stranded DNA antibodies, she was diagnosed with systemic lupus erythematosus (SLE). T2-weighted magnetic resonance imaging revealed bilateral hyperintensities in the putamen. Based on her cognitive impairment, muscle rigidity, and high levels of interleukin-6 in the cerebrospinal fluid, we believed she had developed a complication of a neuropsychiatric disease and administered corticosteroids and intravenous cyclophosphamide therapy. Her cognitive function fully recovered, and her gait disturbance improved. Attending to cognitive impairment in elderly SLE patients is necessary.

Anti-MDA5 Antibody-positive Dermatomyositis Complicated by Autoimmune-associated Hemophagocytic Syndrome that was Successfully Treated with Immunosuppressive Therapy and Plasmapheresis

A 56-year-old Japanese woman with muscle weakness, increased creatine kinase and aldolase levels, and characteristic cutaneous lesions was diagnosed with anti-melanoma differentiation-associated gene 5 antibody (anti-MDA5 antibody)-positive dermatomyositis. She also had interstitial lung disease (ILD). After corticosteroid and tacrolimus combination therapy was started, bicytopenia and elevated serum ferritin and transaminase emerged. Because the bone marrow tissues were hypoplastic with hemophagocytes, she was diagnosed with concomitant autoimmune-associated hemophagocytic syndrome (HPS). Intravenous cyclophosphamide pulse therapy and plasmapheresis were performed. The laboratory findings indicated improved abnormalities, and the ILD did not progress. Anti-MDA5 antibody-positive dermatomyositis can be complicated by HPS.

Podocyte foot process width is a prediction marker for complete renal response at 6 and 12 months after induction therapy in lupus nephritis

Morphological change that includes diffuse effacement of podocyte foot processes is correlated with proteinuria in patients with lupus nephritis (LN). We collected the data of clinico-pathological parameters and assessed foot process width (FPW) as an index of podocyte effacement in 73 patients with LN who had undergone renal biopsy. The multivariate analysis revealed that female gender (OR: 5.288; 95%CI: 1.197-37.29; pu202f=u202f.0267) and FPW (ORu202f=u202f0.999, 95%CIu202f=u202f0.997-0.999, pu202f=u202f.0150) were significantly predictive of a complete renal response (CR) at 6u202fmonths, while lymphocyte counts (ORu202f=u202f1.002; 95%CIu202f=u202f1.001-1.003, pu202f=u202f.0028) and FPW (ORu202f=u202f0.998, 95%CIu202f=u202f0.996-0.999, pu202f=u202f.0027) were significantly predictive of CR at 12u202fmonths. The cut-off point determined by the Classification and Regression Trees algorithm showed that FPW <908.3u202fnm provides the best performance for predicting patients who achieve CR at 12u202fmonths. A smaller FPW appears to be a predictive factor for CR at 6 and 12u202fmonths after induction therapy.

Osteogenic differentiation of fibroblast-like synovial cells in rheumatoid arthritis is induced by microRNA-218 through a ROBO/Slit pathway

BackgroundFibroblast-like synovial cells (FLS) have multilineage differentiation potential including osteoblasts. We aimed to investigate the role of microRNAs during the osteogenic differentiation of rheumatoid arthritis (RA)-FLS.MethodsRA-FLS were differentiated in osteogenic medium for 21xa0days. Osteogenic differentiation was evaluated by alkaline phosphatase (ALP) staining and Alizarin Red staining. MicroRNA (miRNA) array analysis was performed to investigate the differentially expressed miRNAs during osteogenic differentiation. Expression of miR-218-5p (miR-218) during the osteogenic differentiation was determined by quantitative real-time PCR. Transfections with an miR-218 precursor and inhibitor were used to confirm the targets of miR-218 and to analyze the ability of miR-218 to induce osteogenic differentiation. Secreted Dickkopf-1 (DKK1) from FLS transfected with miR-218 precursor/inhibitor or roundabout 1 (ROBO1) knockdown FLS established using ROBO1-small interfering RNA (siRNA) were measured by ELISA.ResultsThe miRNA array revealed that 12 miRNAs were upregulated and 24 miRNAs were downregulated after osteogenic differentiation. We observed that the level of miR-218 rose in the early phase of osteogenic differentiation and then decreased. Pro-inflammatory cytokines modified the expression of miR-218. The induction of miR-218 in RA-FLS decreased ROBO1 expression, and promoted osteogenic differentiation. Both the overexpression of miR-218 and the knockdown of ROBO1 in RA-FLS decreased DKK1 secretion.ConclusionWe identified miR-218 as a crucial inducer of the osteogenic differentiation of RA-FLS. MiR-218 modulates the osteogenic differentiation of RA-FLS through the ROBO1/DKK-1 axis. The induction of the osteogenic differentiation of proliferating RA-FLS through the provision of miR-218 into RA-FLS or by boosting the cellular reservoir of miR-218 might thus become a therapeutic strategy for RA.

SAT0589 Musculoskeletal manifestations occur predominantly in patients with older onset familial mediterranean fever

Background Our previous nation-wide survey showed the clinical manifestations and prevalence of Japanese Familial Mediterranean Fever (FMF) patients. However, the clinical differences between young-onset FMF (YOFMF), adult-onset FMF (AOFMF), and late-onset FMF (LOFMF) have not been yet clarified. Objectives We sought to compare between the clinical profile of patients with AOFMF, LOFMF and YOFMF and to determine the clinical characteristics of them. Methods We enrolled consecutively 395 patients in 2006–2017. Mutation detection in exons 1, 2, 3, and 10 of the MEFV gene was performed. We defined YOFMF, AOFMF and LOFMF as the onset of FMF <20, 20–39 and &x2267;40 years of age, respectively. We compared clinical manifestations and mutations in MEFV gene among these three groups. Results The median age at the onset of YOFMF, AOFMF and LOFMF were 12.5, 28 and 51 years old respectively. A family history of FMF and a mutation in exon 10 of the MEFV gene were significantly more frequent in groups with younger onset ([YOFMF 28%, AOFMF 17%, LOFMF 12%; p<0.01], [YOFMF 51%, AOFMF 33%, LOFMF 19%; p<0.001], respectively). In the accompanying manifestations during the attacks, abdominal pain and chest pain were significantly more frequent in groups with younger onset ([YOFMF 64%, AOFMF 56%, LOFMF 30%; p<0.001], [YOFMF 45%, AOFMF 33%, LOFMF 24%; p<0.01], respectively), whereas arthritis and muscle pain were significantly more frequent in groups with older onset ([YOFMF 32%, AOFMF 48%, LOFMF 62%;p<0.001], [YOFMF 8%, AOFMF 18%, LOFMF 26%;p<0.01], respectively). There was no significantly difference in the response to colchicine among the three groups. Conclusions Our results suggest that older onset FMF had a lower percentage of mutations in exon10 of the MEFV gene and predominantly presented arthritis and muscle pain during the attacks. It is thus important to distinguish them from other inflammatory diseases such as gout, adult Still’s disease, and infectious arthritis. Disclosure of Interest None declared