Evaluation of Ministry of Health, Labour and Welfare diagnostic criteria for antineutrophil cytoplasmic antibody-associated vasculitis compared to ACR/EULAR 2022 classification criteria.

OBJECTIVE: This study aimed to evaluate the Ministry of Health, Labour and Welfare (MHLW) diagnostic criteria for antineutrophil cytoplasmic antibody-associated vasculitis compared to the new American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria. METHODS: Two nationwide cohort studies were used, and participants were categorised as having eosinophilic granulomatosis with polyangiitis, granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA) according to the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 and MHLW criteria. RESULTS: Of the entire patient population, only 10 (2.1%) were unclassifiable according to the MHLW probable criteria, while a significant number of patients (71.3%) met at least two criteria. The MHLW probable criteria for MPA had some challenges in differentiating between MPA and eosinophilic granulomatosis with polyangiitis, and the same was true for MHLW probable criteria for GPA in differentiating MPA from GPA. Nevertheless, improved classification results were obtained when the MHLW probable criteria were applied in the order of eosinophilic granulomatosis with polyangiitis, MPA, and GPA. CONCLUSIONS: The application of MHLW criteria could categorise a substantial number of patients with antineutrophil cytoplasmic antibody-associated vasculitis into one of the three antineutrophil cytoplasmic antibody-associated vasculitis diseases. The classification was in accordance with the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria when considering the order of application.

Association of elevated serum carbohydrate antigen 19-9 levels with extensive interstitial lung disease in patients with systemic sclerosis: A cross-sectional study.

AIM: To assess the usefulness of carbohydrate antigen 19-9 (CA19-9) as a biomarker for systemic sclerosis-associated interstitial lung disease (SSc-ILD), using serum samples and clinical parameters of patients with SSc. METHODS: Patients with SSc admitted to Tokyo Women's Medical University Hospital between 2010 and 2021 and those who underwent chest computed tomography (CT) were included. Patients were diagnosed with ILD based on chest CT findings, and SSc-ILD was categorized as either a limited or extensive disease based on chest CT and pulmonary function test findings. Serum CA19-9 levels were measured in 56 patients with SSc and in 32 healthy individuals. Additionally, we evaluated the difference in serum CA19-9 levels between the groups, the correlation with ILD area and pulmonary function, and discriminative performance to diagnose extensive ILD. RESULTS: Of the 56 patients with SSc, 40 (71.4%) had ILD, and 17 (30.4%) were classified as having extensive disease. Serum CA19-9 levels were significantly elevated in patients with extensive disease compared to those with limited disease (median [interquartile range]: 25.7 U/mL [10.1-50.8] vs. 8.8 U/mL [4.5-17.6], p = .02) and correlated with ILD area (r = .30, p = .02). There was no significant correlation between serum CA19-9 level and pulmonary function. The cutoff of CA19-9 for the diagnosis of the extensive disease was determined to be 19.8 U/mL, with a sensitivity of 64% and specificity of 82% and an area under the curve of 0.74 (95% confidence interval 0.58-0.90). CONCLUSION: The serum CA19-9 level may be a useful marker for identifying patients with SSc-ILD with extensive disease.

Antifibrotic effect of apremilast in systemic sclerosis dermal fibroblasts and bleomycin-induced mouse model.

Phosphodiesterase (PDE) 4 inhibitors have been reported to suppress the progression of dermal fibrosis in patients with systemic sclerosis (SSc); however, the precise mechanisms remain to be elucidated. Therefore, we conducted experiments focusing on the antifibrotic and anti-inflammatory effects of apremilast using dermal fibroblasts derived from patients with SSc and an SSc mouse model. Dermal fibroblasts derived from healthy controls and patients with SSc were incubated with apremilast in the presence or absence of 10 ng/ml transforming growth factor (TGF)-ß1 for the measurement of intracellular cAMP levels and evaluation of mRNA and protein expression. A bleomycin-induced dermal fibrosis mouse model was used to evaluate the inhibitory effects of apremilast on the progression of dermal fibrosis. Intracellular cAMP levels were significantly reduced in dermal fibroblasts derived from patients with SSc compared with those derived from healthy controls. Apremilast reduced the mRNA expression of profibrotic markers and the protein expression of type I collagen and Cellular Communication Network Factor 2 (CCN2) in dermal fibroblasts. Additionally, apremilast inhibited the progression of dermal fibrosis in mice, partly by acting on T cells. These results suggest that apremilast may be a potential candidate for treating dermal fibrosis in SSc.

Evaluation of RABBIT risk score in Japanese patients with rheumatoid arthritis starting first bDMARDs: a validation study using the IORRA cohort data.

OBJECTIVE: To examine the ability of the Rheumatoid Arthritis Observation of Biologic Therapy (RABBIT) risk score to predict the occurrence of serious infections in Japanese patients with rheumatoid arthritis (RA), after initiating their first biologic disease-modifying antirheumatic drug (bDMARD). METHODS: We used data from the Institute of Rheumatology, Rheumatoid Arthritis (IORRA) cohort from 2008 to 2020. Patients with RA who were started on their first bDMARDs were included. Those with missing data required to calculate the score were excluded. A receiver operating characteristic (ROC) curve was used to evaluate the discriminatory ability of the RABBIT score. RESULTS: A total of 1,081 patients were enrolled. During the one-year observational period, 23 (1.7%) patients had serious infections; the most frequent one was bacterial pneumonia (n=11, 44%). The median RABBIT score in the serious infection group was significantly higher than that in the non-serious infection group (2.3 [1.5-5.4] vs 1.6 [1.2-2.5], p<0.001). The area under the ROC curve for the occurrence of serious infections was 0.67 (95% confidence interval 0.52-0.79), suggesting that the score had low accuracy. CONCLUSION: Our present study revealed that the RABBIT risk score did not have sufficient discriminatory ability for predicting the development of severe infections in Japanese patients with rheumatoid arthritis after initiating their first bDMARD.

Development of microscopic polyangiitis following idiopathic pleuroparenchymal l fibroelastosis: A case report.

Idiopathic pleuroparenchymal fibroelastosis (PPFE) is a rare type of idiopathic interstitial pneumonia, which is characterised by pleural fibrosis and subjacent parenchymal fibroelastosis of the upper lobes. Herein, we present a case of microscopic polyangiitis (MPA) following PPFE. The patient had abnormal shadows on chest radiographs 15 years before the onset of MPA, and the patient was diagnosed with PPFE. Four years after the PPFE diagnosis, the patient was diagnosed with MPA based on persistent fever, purpura, mononeuritis multiplex, myeloperoxidase-antineutrophil cytoplasmic antibody positivity, and pathological findings of peritubular capillaritis on kidney biopsy. The patient was treated with glucocorticoids, including methylprednisolone pulse therapy and rituximab, followed by maintenance therapy with rituximab. One year after treatment, the PPFE had not worsened. PPFE occasionally occurs secondary to connective tissue disease, including MPA; however, to the best of our knowledge, this is the first report of PPFE preceding MPA. Our case suggests that PPFE, as other interstitial lung diseases, may be associated with MPA and precede the onset of MPA. The accumulation of more cases is needed to clarify the characteristics of MPA-associated PPFE.

A case of systemic lupus erythematosus having concurrent Evans syndrome and acquired thrombotic thrombocytopenic purpura.

An 18-year-old Japanese woman with systemic lupus erythematosus experienced dyspnoea, headache, tinnitus, and purpura for 2 weeks and was admitted to our hospital. The patient had been diagnosed with systemic lupus erythematosus and secondary immune thrombocytopenia 8 years before and treated with high-dose prednisolone and mycophenolate mofetil. Since the blood test on admission showed haemolytic anaemia with a positive direct Coombs test and anti-glycoprotein IIb/IIIa antibodies, the patient was initially diagnosed with Evans syndrome (ES). The patient was treated with pulse intravenous methylprednisolone followed by 45 mg/day prednisolone; however, the patient's platelet count did not normalise. Based on a low level of a disintegrin-like and metalloproteinase with thrombospondin type 1 motif 13 (ADAMTS-13) activity and a high level of ADAMTS-13 inhibitors, a diagnosis of acquired thrombotic thrombocytopenic purpura (TTP) was confirmed. After undergoing therapeutic plasma exchange for 6 consecutive days, the patient's platelet count recovered rapidly. Although concurrent acquired TTP and ES have not been reported previously, the findings from this case highlight the importance of measuring ADAMTS-13 activity and inhibitors to rule out acquired TTP, especially when ES is refractory to glucocorticoids.

Validation of new ACR/EULAR 2022 classification criteria for anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: The objective of this study was to compare the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria with the previous classification algorithm for anti-neutrophil cytoplasmic antibody-associated vasculitis. METHODS: We used data from two nationwide, prospective, inception cohort studies. The enrolled patients were classified as having eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA) according to the new criteria; these criteria were compared with Watts' algorithm. RESULTS: Among 477 patients, 10.7%, 9.9%, and 75.6% were classified as having EGPA, GPA, and MPA, respectively; 6.1% were unclassifiable. Three patients met both the EGPA and MPA criteria, and eight patients met both the GPA and MPA criteria. Of 78 patients with GPA classified using Watts' algorithm, 27 (34.6%) patients were reclassified as having MPA. Ear, nose, and throat involvement was significantly less frequent in patients reclassified as having MPA than in those reclassified as having GPA. Of 73 patients unclassifiable using Watts' algorithm, 62 were reclassified as having MPA. All patients reclassified as having MPA were myeloperoxidase-anti-neutrophil cytoplasmic antibody positive, and 46 had interstitial lung disease. CONCLUSION: Although the American College of Rheumatology/European Alliance of Associations for Rheumatology 2022 criteria cause overlapping multiple criteria fulfilments in some patients, those items contribute to classifying unclassifiable patients using Watts' algorithm into MPA.

A case of Takayasu arteritis complicated with acute pericarditis at initial presentation.

Takayasu arteritis (TAK) is a rare, large-vessel vasculitis, frequently presenting at approximately 20 years of age. Patients with TAK without characteristic clinical findings are sometimes left undiagnosed and are followed by a fever of unknown origin; delayed diagnosis may lead to irreversible ischaemia and organ damage. Here, we report a case of an 18-year-old woman with TAK complicated by acute pericarditis at initial presentation. She was diagnosed with idiopathic acute pericarditis and treated with non-steroidal anti-inflammatory drugs (NSAIDs). However, the patient's fever and pain in the chest and upper back persisted. On admission to our hospital, magnetic resonance angiography and ultrasonography revealed wall thickening in the common carotid artery, subclavian artery, and aorta, along with vascular narrowing in the celiac, superior mesenteric, and bilateral renal arteries. The patient was diagnosed with TAK and treated with glucocorticoids, including methylprednisolone pulse therapy, and azathioprine. The treatment improved the patient's signs and symptoms, and pericardial effusion decreased. Acute pericarditis is a rare manifestation of TAK, but it is important to differentiate diseases, including TAK in patients with acute pericarditis who fail to respond to 2-3 weeks of conventional therapy with NSAIDs.

Systematic review and meta-analysis for 2023 clinical practice guidelines of the Japan Research Committee of the Ministry of Health, Labour, and Welfare for Intractable Vasculitis for the management of ANCA-associated vasculitis.

OBJECTIVES: The objective of this study is to provide evidence for the revision of clinical practice guidelines for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis by the Japan Research Committee for Intractable Vasculitis. METHODS: PubMed, CENTRAL, and the Japan Medical Abstracts Society databases were searched for articles published between 2015 and 2020 to update the systematic review for existing clinical questions, while PubMed, CENTRAL, EMBASE, and the Japan Medical Abstracts Society were searched for articles published between 2000 and 2020 to conduct a systematic review for newly developed clinical questions. The certainty of evidence was assessed with the GRADE approach. RESULTS: For remission induction, when used in conjunction with cyclophosphamide or rituximab, reduced-dose glucocorticoid lowered the risk of serious adverse events compared to standard-dose glucocorticoid. Avacopan improved sustained remission at 12 months compared to high-dose glucocorticoid. Addition of plasma exchange to remission induction therapy did not reduce the risk of death, end-stage kidney disease, or relapse. For remission maintenance, rituximab reduced the risk of relapse compared to azathioprine. Long-term rituximab or azathioprine reduced the risk of relapse compared to short-term rituximab or azathioprine, respectively. CONCLUSIONS: This systematic review provided evidence required to develop the 2023 clinical practice guideline for the management of ANCA-associated vasculitis.

No obvious toxicological influences of 50 µL microsampling from rats administered phenacetin as a drug with hematological toxicity.

According to ICH S3A Q&A focusing on microsampling, its application should be avoided in main study animals for test drugs that could exacerbate hematological parameters with frequent blood sampling. However, no study has reported the effects of microsampling on toxicity parameters of drugs known to induce hematological toxicity. Therefore, we assessed the toxicological effects of serial microsampling on rats treated with phenacetin as a model drug. In a common 28-day study, 50 µL of microsampling was performed at 6-time points on days 1 to 2 and 7-time points on days 27 to 28 from the jugular vein of Sprague Dawley rats. The study was performed independently by two organizations. The toxicological influence of microsampling was evaluated on body weight, food consumption, hematology, blood clinical chemistry, urine parameters, organ weights, and tissue pathology. Phenacetin treatments induced significant changes of various hematological parameters (including hemoglobin and reticulocytes), some organ weights (including liver and spleen), and some hematology-related pathological parameters in the liver, spleen and bone marrow. Meanwhile, serial microsampling exhibited minimal influence on the assessed parameters, although 20 parameters showed statistical differences mostly at one organization. The current results support the notion that serial 50 µL microsampling from the jugular vein had minimal impacts on overall toxicological profiles even in rats treated with a drug inducing hematological toxicity, but the potential adverse effect on certain parameters could not be fully excluded. Accordingly, this microsampling technique has possibility to be employed even for non-clinical rat toxicity studies using drugs with potentially hematological toxicity.

Impact of concomitant chronic kidney disease on hospitalised infections and remission in patients with rheumatoid arthritis: results from the IORRA cohort.

OBJECTIVES: To investigate the impact of concomitant chronic kidney disease (CKD) on unfavourable clinical events and remission in Japanese patients with rheumatoid arthritis (RA). METHODS: We included 5103 patients with RA and CKD from the Institute of Rheumatology Rheumatoid Arthritis (IORRA) cohort in 2012. CKD stages were classified into four groups: CKD with normal eGFR ≥60 ml/min/1.73 m2 and proteinuria; mild CKD, eGFR ≥45 to < 60; moderate CKD, eGFR ≥30 to < 45; and severe CKD, eGFR <30. We assessed the association between concomitant CKD and the occurrence of unfavourable clinical events or achieving remission during a 5-year observational period. RESULTS: Of the 5103 patients with RA, 686 (86.6%) had CKD. Concomitant CKD was associated with hospitalised infections [adjusted hazard ratio (aHR) 1.52, 95% confidence interval (CI) 1.07-2.13, p = .02], especially in the moderate to severe CKD group (aHR 1.93, 95% CI 1.12-3.13, p = .02). Of all subjects, 2407 (47.2%) had active RA at baseline and 401 (16.7%) had CKD. Concomitant CKD was also associated with the failure of achieving remission (aHR 0.82, 95% CI 0.68-0.99, p = .04). CONCLUSIONS: Concomitant CKD was a risk factor for hospitalised infections in Japanese patients with RA and failure of achieving remission in patients with active RA.

Biodistribution studies for cell therapy products: Current status and issues.

Information on the biodistribution (BD) of cell therapy products (CTPs) is essential for prediction and assessment of their efficacy and toxicity profiles in non-clinical and clinical studies. To conduct BD studies, it is necessary to understand regulatory requirements, implementation status, and analytical methods. This review aimed at surveying international and Japanese trends concerning the BD study for CTPs and the following subjects were investigated, which were considered particularly important: 1) comparison of guidelines to understand the regulatory status of BD studies in a global setting; 2) case studies of the BD study using databases to understand its current status in cell therapy; 3) case studies on quantitative polymerase chain reaction (qPCR) used primarily in non-clinical BD studies for CTPs; and 4) survey of imaging methods used for non-clinical and clinical BD studies. The results in this review will be a useful resource for implementing BD studies.

Characteristics of Japanese patients with systemic sclerosis complicated with calcinosis.

AIM: Calcinosis is often observed in systemic sclerosis (SSc), but its pathogenesis remains unclear. The aim of the present study was to explore the association of clinical features with calcinosis in patients with SSc. METHODS: A retrospective cohort study was performed analyzing 416 SSc patients from our SSc database. We examined the clinical features with relation to calcinosis and SSc. RESULTS: Calcinosis was observed in 24.0% of patients with SSc. The group with calcinosis comprised more female patients (P < 0.05) and diffuse cutaneous types (P < 0.001) than the group without calcinosis. Complications of Raynaud's phenomenon (P < 0.05), nail fold bleeding (NFB) (P < 0.001), peripheral bone resorption (P < 0.001), myositis (P < 0.001), and pulmonary hypertension (P < 0.05) were more frequently observed in patients with calcinosis compared with those without calcinosis. The group with calcinosis had a higher modified Rodnan total skin-thickness score (mRSS) than the group without calcinosis (P < 0.001). The factors that affected calcinosis in multivariable analysis were peripheral bone resorption (partial correlation coefficient 0.46, 34%), anti-Scl-70 antibody (partial correlation coefficient 0.29, 20%), diffuse type (partial correlation coefficient 0.34, 16%) and NFB (partial correlation coefficient 0.23, 11.2%). CONCLUSIONS: Calcinosis in SSc is associated with Raynaud's phenomenon, NFB, and pulmonary hypertension, so peripheral circulatory insufficiency seems to be one of the causes of calcinosis. Furthermore, as it is related to mRSS and the diffuse cutaneous type, common factors related to skin fibrosis are considered to be involved.

Single nucleotide polymorphisms of the HIF1A gene are associated with susceptibility to pulmonary arterial hypertension in systemic sclerosis and contribute to SSc-PAH disease severity.

AIM: Hypoxia-inducible factor (HIF)1α is induced by endothelial cells under hypoxic conditions, suggesting that HIF1α may be involved in vascular impairment in patients with systemic sclerosis (SSc). The purpose of this study was to evaluate whether single nucleotide polymorphisms (SNPs) of the HIF1A gene are associated with susceptibility to SSc and its complications, including pulmonary arterial hypertension (PAH). METHOD: This study involved 182 Japanese SSc patients (discovery cohort) and 178 healthy controls. Four SNPs (rs11549465, rs11549467, rs1957757, and rs12434438) of the HIF1A gene were genotyped using specific TaqMan probes. We also employed another SSc cohort (N = 135) to validate the significant results of SNPs found in the discovery SSc cohort. RESULTS: The frequencies of the four SNPs did not show any significant differences between the SSc and healthy control groups. The AA genotype at rs12434438 was significantly higher in SSc patients with PAH than in those without PAH (P = .012). These results were validated using another SSc cohort (N = 135, P = .006). Moreover, the AA genotype was significantly associated with the severity of PAH. CONCLUSION: Although HIF1A gene polymorphisms were not associated with susceptibility to SSc, the AA genotype at rs12434438 was associated with a subset of SSc patients with severe PAH, suggesting that the rs12434438 SNP may contribute to the development of PAH with SSc.

Development of a bioanalytical method for circulating human T cells in animals using Arthrobacter luteus-based quantitative polymerase chain reaction and its application in preclinical biodistribution studies.

INTRODUCTION: In the development of cell therapy products for human use, studies on the biodistribution of transplanted cells in animals are important for assessing the safety and efficacy of these products. Although a few reports have described the biodistribution of human cells in animals using Arthrobacter luteus-based-polymerase chain reaction (Alu-PCR), most have used genomic DNA or synthetic oligonucleotide as calibrators, as opposed to actual cells. In addition, bioanalytical variability in the quantification of cells with respect to specificity, selectivity, accuracy, and precision, has not been evaluated. Accordingly, in this study, we validated the utility of this bioanalytical method for human T cells in mice to establish assay performance using cells as a calibrator. METHODS: A standard curve was constructed for the addition of cell lysates to mouse tissues and blood, and DNA was extracted. Alu-PCR was applied for the quantification of human peripheral blood CD8+ T cells in mice. To determine assay performance, we evaluated accuracy, precision, selectivity, specificity, and stability. In vivo cell kinetics and biodistribution were investigated based on intravenous administration of human T cells to mice. RESULTS: Alu-PCR enabled us to specifically detect human T cells in mouse blood and tissues. The lower detection limit of Alu-PCR was 10 cells/15 mg tissue (7.5 mg for spleen and lung) or cells/50 µL blood. Given that PCR threshold cycle (Cq) values among mouse samples (blood, liver spleen, lung, heart, and kidney) show slight variation, calibration curves should be generated using the same tissue as used for the assay. Most coefficients of variation in the assay were within 30%. The cell kinetics of administered human T cells in mice were successfully evaluated using the established Alu-qPCR. CONCLUSIONS: The Alu-PCR technique developed in this study showed sufficient specificity and sensitivity in detecting human peripheral blood CD8+ T cells in mice. This technique, which targets the primate-specific Alu gene, is applicable for quantifying transplanted human cells in animals without the necessity of cell labeling. The data presented herein will be useful for standardizing bioanalytical approaches in biodistribution studies of cell therapy products.

Idiopathic Multicentric Castleman Disease with Autoimmune Hemolytic Anemia and Production of Anti-drug Antibody against Tocilizumab.

Idiopathic multicentric Castleman disease (iMCD) is a rare lymphoproliferative disorder, and only a few cases have been reported to be complicated with autoimmune hemolytic anemia (AIHA). A 43-year-old man who presented with multiple swollen lymph nodes was diagnosed with iMCD. He was also diagnosed with AIHA based on laboratory findings, including the results of a bone marrow aspiration study. The patient was treated with tocilizumab; however, the effect was limited, probably due to anti-drug antibodies. Tocilizumab was therefore switched to rituximab, and his anemia was improved. Complication with AIHA should be carefully considered when iMCD patients present with severe anemia.

Antifibrotic effects of 2-carba cyclic phosphatidic acid (2ccPA) in systemic sclerosis: contribution to the novel treatment.

BACKGROUND: Cyclic phosphatidic acid (cPA) has an inhibitory effect on the autotaxin (ATX)/lysophosphatidic acid (LPA) axis, which has been implicated to play an important role in the progression of fibrosis in systemic sclerosis (SSc). The purpose of this study is to assess the antifibrotic activity of cPA for the treatment of SSc using SSc skin fibroblasts and an animal model of bleomycin-induced skin fibrosis. METHODS: We used a chemically stable derivative of cPA (2ccPA). First, we investigated the effect of 2ccPA on extracellular matrix (ECM) expression in skin fibroblasts. Next, the effect of 2ccPA on the intracellular cAMP levels was determined to investigate the mechanisms of the antifibrotic activity of 2ccPA. Finally, we administered 2ccPA to bleomycin-induced SSc model mice to evaluate whether 2ccPA prevented the progression of skin fibrosis. RESULTS: 2ccPA decreased ECM expression in SSc skin fibroblasts and TGF-ß1-treated healthy skin fibroblasts without LPA stimulation. 2ccPA increased the intracellular cAMP levels in skin fibroblasts, suggesting that the antifibrotic effect of 2ccPA was the consequence of the increase in the intracellular cAMP levels. Administration of 2ccPA also ameliorated the progression of bleomycin-induced skin fibrosis in mice. CONCLUSIONS: Our data indicated that 2ccPA had inhibitory effects on the progression of skin fibrosis by abrogating ECM production from activated skin fibroblasts. These cells were repressed, at least in part, by increased intracellular cAMP levels. 2ccPA may be able to be used to treat fibrotic lesions in SSc.

Disposition and metabolism of the G protein-coupled receptor 40 agonist TAK-875 (fasiglifam) in rats, dogs, and humans.

The absorption, distribution, metabolism, and excretion of fasiglifam were investigated in rats, dogs, and humans. The absolute oral bioavailability of fasiglifam was high in all species (>76.0%). After oral administration of [14C]fasiglifam, the administered radioactivity was quantitatively recovered and the major route of excretion of radioactivity was via feces in all species. Fasiglifam was a major component in the plasma and feces in all species. Its oxidative metabolite (M-I) was observed as a minor metabolite in rat and human plasma (<10% of plasma radioactivity). In human plasma, hydroxylated fasiglifam (T-1676427), the glucuronide of fasiglifam (fasiglifam-G), and the glucuronide of M-I were detected as additional minor metabolites (<2% of plasma radioactivity). None of these metabolites were specific to humans. Fasiglifam-G was the major component in the rat and dog bile. In vitro cytochrome P450 (CYP) and uridine diphosphate glucuronosyltransferase (UGT) reaction phenotyping indicated that oxidation (to form M-I and T-1676427) and glucuronidation of fasiglifam are mainly mediated by CYP3A4/5 and UGT1A3, respectively. Fasiglifam and fasiglifam-G are substrates of BCRP and Mrp2/MRP2, respectively. Glucuronidation of fasiglifam-G was found to be the predominant elimination pathway of fasiglifam in all species tested, including humans.

The effect of elevated α1-acid glycoprotein on the pharmacokinetics of TAK-272 (SCO-272), an orally active renin inhibitor, in rats.

The pharmacokinetics of TAK-272 (SCO-272), an orally active renin inhibitor, was investigated in rats with subcutaneously injected turpentine oil, which was an inflammation animal model. Following intravenous administration of TAK-272 to the turpentine-treated rats, the systemic clearance and volume of distribution decreased with the elevated plasma α1-acid glycoprotein (AGP) levels. The elevated plasma AGP levels were negatively correlated with the plasma unbound fraction of TAK-272 in the rats. Although the AUCs of total TAK-272 in the turpentine-treated rats were higher than those in the control rats after intravenous and oral administration, those of unbound TAK-272, which seem to directly contribute to the pharmacological effect and safety, were nearly equal between the turpentine-treated and control rats in the respective dose routes. TAK-272 has been shown to primarily bind to AGP in the human plasma. These results strongly suggested that the pharmacokinetic of TAK-272 in humans would also be affected by the variation in the plasma AGP levels and should be discussed with not only the total concentrations but also the unbound concentrations in the clinical trial for patients with elevated plasma AGP levels.

Outer Membrane Protein of Gut Commensal Microorganism Induces Autoantibody Production and Extra-Intestinal Gland Inflammation in Mice.

Gut commensal microorganisms have been linked with chronic inflammation at the extra-intestinal niche of the body. The object of the study was to investigate on the chronic effects of a gut commensal Escherichia coli on extra-intestinal glands. The presence of autoimmune response was diagnosed by autoantibody levels and histological methods. Repeated injection of E. coli induced mononuclear cell inflammation in the Harderian and submandibular salivary glands of female C57BL/6 mice. Inflammation was reproduced by adoptive transfer of splenocytes to immune-deficient Rag2 knockout mice and CD4⁺ T cells to mature T cell-deficient TCRß-TCRδ knockout mice. MALDI TOF mass spectrometry of the protein to which sera of E. coli-treated mice reacted was determined as the outer membrane protein A (OmpA) of E. coli. Multiple genera of the Enterobacteriaceae possessed OmpA with high amino-acid sequence similarities. Repeated injection of recombinant OmpA reproduced mononuclear cell inflammation of the Harderian and salivary glands in mice and elevation of autoantibodies against Sjögren's-syndrome-related antigens SSA/Ro and SSB/La. The results indicated the possibility of chronic stimuli from commensal bacteria-originated components as a pathogenic factor to elicit extra-intestinal autoimmunity.