RESUMO
OBJECTIVES: Pulmonary hypertension (PH) in patients with CTD is a heterogeneous condition affected by left heart disease, chronic lung disease and thromboembolism as well as pulmonary vascular disease. Recent studies using cardiac magnetic resonance (CMR) have shown that right ventricular dysfunction is predictive for mortality in patients with PH, but limited to pulmonary arterial hypertension. This study aimed to analyse prognostic factors in PH-CTD. METHODS: This retrospective analysis comprised 84 CTD patients, including SSc, who underwent both CMR and right heart catheterization from 2008 to 2018. Demographics, laboratory findings, and haemodynamic and morphological parameters were extracted. The prognostic value of each parameter was evaluated by multivariate analysis using covariables derived from propensity score to control confounding factors. RESULTS: Of 84 patients, 65 had right heart catheterization-confirmed PH (54 pulmonary arterial hypertension, 11 non-pulmonary arterial hypertension). Nine out of these PH patients died during a median follow-up period of 25 months. In 65 patients with PH, right ventricular end-diastolic dimension index (RVEDDI) evaluated by CMR was independently associated with mortality (hazard ratio 1.24; 95% CI: 1.08-1.46; P = 0.003). In a receiver operating characteristic analysis, RVEDDI highly predicted mortality, with area under the curve of 0.87. The 0.5-2-year follow-up data revealed that RVEDDI in both survivors and non-survivors did not significantly change over the clinical course, leading to the possibility that an early determination of RVEDDI could predict the prognosis. CONCLUSION: RVEDDI simply evaluated by CMR could serve as a significant predictor of mortality in PH-CTD. A further validation cohort study is needed to confirm its usability.
Assuntos
Doenças do Tecido Conjuntivo/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Hipertensão Pulmonar/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Idoso , Cateterismo Cardíaco , Doenças do Tecido Conjuntivo/complicações , Feminino , Humanos , Hipertensão Pulmonar/complicações , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos RetrospectivosRESUMO
Objectives: To analyze the effects of tocilizumab on peripheral B-cell subpopulation and its ability to produce anti-cyclic citrullinated peptide (CCP) antibody in patients with rheumatoid arthritis (RA).Methods: Thirteen consecutive RA patients initiated with tocilizumab were enrolled in our prospective study. Anti-CCP antibody titers and clinical parameters were evaluated during treatment. Peripheral blood B-cell subsets were analyzed using flow cytometry according to the Human Immunology Project.Results: Disease activity was significantly improved and anti-CCP antibody titers significantly decreased at week 24 compared to baseline. The percentages of post-switch memory B cells in CD19+ cells transiently increased at week 12, but there was no significant difference in any of the investigated B-cell subpopulations at week 24 compared to baseline. The ratios of post-switch memory to naïve B cells (post-switch/naïve) correlated negatively with anti-CCP antibody titers regardless of the time-points.Conclusion: Our study indicated that tocilizumab has a potential to reduce anti-CCP antibody production presumably by affecting post-switch/naïve ratio, and that anti-CCP antibody titers reflect B-cell distribution/subpopulation. As anti-CCP antibodies are produced in lymph nodes or ectopic lymphoid structures in synovial tissues, not in circulation, transient increment of post-switch memory B cells after tocilizumab treatment may reflect the altered balance of B-cell distribution between circulation and arthritic joints, resulting in suppressed production of anti-CCP antibody in situ.
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Anticorpos Antiproteína Citrulinada/sangue , Anticorpos Monoclonais Humanizados/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Imunossupressores/uso terapêutico , Adulto , Artrite Reumatoide/sangue , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Objectives: Thrombocytopenia is frequently observed in antiphospholipid antibody (aPL) carriers. Due to the paradoxical risks of thrombosis and hemorrhage, the management of aPL-associated thrombocytopenia (APAT) is often deductive. We aimed to investigate the efficacy and safety of therapeutic approaches for APAT through a systematic review.Methods: Four therapeutic approaches for APAT, including antiplatelet agents, glucocorticoids, splenectomy and thrombopoietin receptor agonists, were selected. Clinical trials evaluating therapeutic outcomes including the remission, complications, mortality and relapse, were searched in MEDLINE, EMBASE and CENTRAL from the inception dates to 28 November 2016. A meta-analysis was performed to calculate risk ratios (RRs) and 95% confidence intervals (CIs) using random-effects models.Results: Out of 1407 papers, eight controlled clinical trials were included. In patients with APAT, the remission rates were higher in patients on glucocorticoids (RR 8.33 [95% CI 3.07-22.6]) or splenectomy (RR 8.37 [95% CI 1.61-43.7]) than in patients without those treatments. There was no significant association between glucocorticoids and thrombosis (RR 1.57 [95% CI, 0.17-14.9]) or between splenectomy and hemorrhage (RR 0.17 [95% CI 0.02-1.28]). The extracted data of mortality and relapse rate were not available for synthesis.Conclusion: Glucocorticoids or splenectomy seemed suitable therapeutic approaches for APAT.
Assuntos
Anticorpos Antifosfolipídeos/imunologia , Glucocorticoides/uso terapêutico , Hemorragia/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Esplenectomia/métodos , Trombocitopenia/terapia , Trombose/prevenção & controle , Anticorpos Antifosfolipídeos/sangue , Hemorragia/etiologia , Humanos , Receptores de Trombopoetina/agonistas , Trombocitopenia/sangue , Trombocitopenia/imunologia , Trombose/etiologiaRESUMO
Recurrent pregnancy loss (RPL) is often considered idiopathic, however excessive complement activation has been observed in pregnancy related manifestations. Anti-C1q antibodies (anti-C1q) are associated with the activation of complement pathway in lupus patients, while it remains unclear in RPL. Firstly, we showed that both the prevalence and titre of anti-C1q were significantly higher in unexplained RPL than in healthy parous individuals. Secondly, we established the murine model of anti-C1q induced pregnancy loss using a monoclonal anti-mouse C1q antibody, JL-1. In mice treated with JL-1, high ratio of pregnancy loss and fetal growth restriction were frequently observed and complement activation occurred. C5a receptor (C5aR) blockade cancelled these pathogenic changes in mice treated with JL-1. In conclusion, our study reveals an association between the prevalence of anti-C1q and RPL. Additionally, our murine model has indicated that anti-C1q can induce reproductive failure, which might be ameliorated by therapy targeting the C5-C5aR axis.
Assuntos
Aborto Habitual/imunologia , Autoanticorpos/metabolismo , Complemento C1q/imunologia , Complemento C5/metabolismo , Receptor da Anafilatoxina C5a/antagonistas & inibidores , Adulto , Animais , Anticorpos Bloqueadores/administração & dosagem , Autoanticorpos/administração & dosagem , Complemento C1q/metabolismo , Estudos Transversais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estudos Retrospectivos , Transdução de SinaisRESUMO
OBJECTIVE: Idiopathic osteonecrosis of the femoral head (ION) is a common complication of SLE associated with CS therapy. Although the pathogenesis of ION involves local bone ischaemia favoured by thrombophilia, the involvement of aPL in lupus ION remains to be elucidated. We have previously reported the aPL score (aPL-S) as a quantitative marker of aPL and the development of thrombotic events in autoimmune diseases. The aim of this study was to identify the impact of aPL on the development of ION using aPL-S. METHODS: This was a single-centre retrospective study comprising 88 consecutive SLE patients who underwent MRI of the hip joints from January 2000 to March 2017. Baseline characteristics, pharmacotherapy and total hip arthroplasty performed during follow-up were evaluated. RESULTS: The presence of ION was confirmed by MRI scan in 38 patients (43.1%). Male gender, positivity of any aPL, aPL-S, high aPL-S (≥30) and high dose of CS were identified as risk factors for ION by univariate analysis. Multivariate analysis revealed high aPL-S (odds ratio 5.12, 95% CI 1.18-29.79) and use of high-dose CS (odds ratio 10.25, 95% CI 3.00-48.38) as independent variables. Kaplan-Meier analysis showed that patients with high aPL-S received total hip arthroplasty more frequently than those without aPL (P = 0.010). CONCLUSIONS: We newly identified high aPL-S as an important risk factor for ION development in SLE, suggesting the involvement of aPL-induced coagulopathy in the pathophysiology of lupus ION.
Assuntos
Corticosteroides/efeitos adversos , Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/complicações , Necrose da Cabeça do Fêmur/induzido quimicamente , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Adulto , Síndrome Antifosfolipídica/induzido quimicamente , Síndrome Antifosfolipídica/imunologia , Biomarcadores , Feminino , Necrose da Cabeça do Fêmur/imunologia , Humanos , Modelos Logísticos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Retrospectivos , Fatores de RiscoRESUMO
OBJECTIVE: Warfarin is regarded as the standard treatment for preventing thrombotic events in APS, but the recurrence rate is still high. Dual antiplatelet therapy (DAPT) has been shown to be effective for the prevention of acute coronary syndrome or stroke. The objective of this study was to evaluate the efficacy of DAPT for the prevention of thrombosis recurrence in APS patients with history of arterial thrombosis. METHODS: This retrospective cohort study of APS patients was conducted at Hokkaido University Hospital between 1990 and 2016. The secondary prophylactic effects and safety of warfarin monotherapy (Wf), antiplatelet monotherapy (AP), warfarin and antiplatelet combination therapy (Wf + AP) and DAPT were evaluated. The primary endpoints were set as thrombosis-free and adverse events-free survival period. Adverse events were defined as severe bleeding and death. RESULTS: A total of 90 APS patients were enrolled. Thrombotic recurrence was found in 40 patients (35 arterial and 5 venous thromboses) and serious adverse events in 20 patients (9 severe bleeding events and 14 deaths). Kaplan-Meier analysis demonstrated a 10-year recurrence-free survival rate of 62%. The recurrence rate per 100 patient-years was as follows: Wf: 11.6, AP: 5.5, Wf: + AP: 3.7, DAPT: 1.8. We demonstrated that DAPT significantly reduced the rate of recurrence compared with Wf (log-rank P = 0.001). There were no significant differences in the rate of serious adverse events among the groups. CONCLUSION: DAPT might be considered as an effective and safe option for the prophylaxis of recurrent arterial thrombosis in APS.
Assuntos
Anticoagulantes/administração & dosagem , Síndrome Antifosfolipídica/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Prevenção Secundária/métodos , Trombose/prevenção & controle , Adulto , Síndrome Antifosfolipídica/complicações , Terapia Antiplaquetária Dupla , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Trombose/etiologia , Resultado do Tratamento , Varfarina/administração & dosagemRESUMO
OBJECTIVES: Rheumatoid arthritis (RA) is an autoimmune polyarthritis, in which fibroblast-like synoviocytes (FLS) play a key role in cartilage and bone destruction through tumour-like proliferation and invasiveness. Considering still unsatisfactory remission rate in RA even under treatment with biological disease-modifying antirheumatic drugs, novel therapeutic strategy for treatment-resistant RA is still awaited. In this study, we analysed the expression and function of Ras guanine nucleotide-releasing proteins (RASGRPs), guanine exchange factors for small GTPase Ras, in FLS as a potential therapeutic target for RA. METHODS: The expression of RASGRPs mRNA was quantified by a real-time PCR assay in FLS isolated from synovial tissue samples. RASGRP2 protein was also evaluated immunohistochemically. Then, we transiently transfected FLS with RASGRP2 expression vector and assessed their proliferation, adhesion, migration and invasion by cellular functional assays and downstream signalling activation using immunoblot. Finally, the therapeutic effect of RASGRP2 silencing was evaluated in type-II collagen-induced arthritis rats. RESULTS: RASGRP2 was abundantly expressed in FLS from RA synovium, whereas scarcely found in those from osteoarthritis. Expression of RASGRP2 in RA-FLS was enhanced by transforming growth factor-beta. RASGRP2 activated RAP-1, subsequently affecting nuclear factor kappa-light-chain-enhancer of activated B cells pathway and actin dynamics in FLS. RASGRP2-overexpressed FLS had increased abilities of adhesion, migration and interleukin (IL)-6 production. Silencing of RASGRP2 using the intra-articular injection of Rasgrp2-specific siRNAs dampened experimental arthritis in rats by inhibiting pannus formation. CONCLUSIONS: RASGRP2 was identified to be involved in the pathogenesis of RA by promoting adhesion, migration and IL-6 production from FLS, proposed as a potential novel non-immunosuppressive therapeutic target for RA.
Assuntos
Artrite Reumatoide/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Membrana Sinovial/metabolismo , Sinoviócitos/metabolismo , Animais , Artrite Experimental/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Fibroblastos/metabolismo , Humanos , RatosRESUMO
OBJECTIVES: The objective of this study is to elucidate the efficacy and safety of autologous haematopoietic stem cell transplantation (HSCT) for Japanese patients with systemic sclerosis (SSc). METHODS: A phase II clinical trial included SSc patients diagnosed within the last three years having at least one of the following clinical features: diffuse skin sclerosis with modified Rodman total thickness skin score (mRSS) ≥ 15, refractory digital ulcer or interstitial lung disease (ILD). HSCT were performed after conditioning using cyclophosphamide. RESULTS: Fourteen patients were enrolled and underwent HSCT. Median follow-up period was 137 months. Overall survival or event-free survival rate was 93% or 40% at 10 years, respectively. Eight patients (57%) achieved more than a 50% decrease in mRSS from baseline within six months after HSCT. Six patients (43%) required additional immunosuppressive treatments due to progression of diffuse skin sclerosis and/or ILD during follow-up period. Adverse events related to HSCT occurred in six patients (43%). Severe cardiomyopathy occurred in two patients, and one of them had a fatal course. CONCLUSION: HSCT is a feasible treatment bringing favourable results to more than half of our patients with SSc. Careful selection of the patients is essential for whom benefited from HSCT, considering the risk-benefit balance of the treatment.
Assuntos
Cardiomiopatias/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Escleroderma Sistêmico/terapia , Adulto , Cardiomiopatias/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo/efeitos adversosRESUMO
OBJECTIVES: The aim of this study was to clarify the consequences of Mx1, one of the IFN-inducible proteins, in the peripheral blood as well as in renal tissues in patients with systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Mx1 protein concentrations in (PBMCs) from 18 SLE patients mostly in their stable disease status, 11 IgA nephropathy (IgAN) patients, 5 ANCA-associated vasculitis (AAV) patients and 16 healthy controls were measured using enzyme-linked immunosorbent assay (ELISA). Mx1 expression in renal specimens from 18 patients with lupus nephritis (LN), 18 with IgAN and 10 with AAV were evaluated using immunohistochemistry. RESULTS: Mx1 protein concentrations in lysates of PBMCs were significantly higher in SLE patients compared with those in other three groups. Mx1-positive area in renal tissues was significantly dominant in both glomeruli and renal tubules of LN compared with other renal diseases. Renal Mx1 protein levels were lower in LN after immunosuppressive treatment, compared with those from immunosuppressant-naïve patients. CONCLUSION: Mx1 levels were upregulated in lupus peripheral blood even when their disease activities were stable. On the other hand, Mx1 was highly expressed in kidneys from patients with LN before treatment, which was decreased after immunosuppressive treatment. These results suggest that Mx1 is a potential marker for the diagnosis of SLE in the peripheral blood and also for the activity of lupus nephritis in the kidney.
Assuntos
Rim/metabolismo , Nefrite Lúpica/metabolismo , Proteínas de Resistência a Myxovirus/metabolismo , Adulto , Feminino , Humanos , Imunossupressores/uso terapêutico , Interferon Tipo I/uso terapêutico , Nefrite Lúpica/sangue , Nefrite Lúpica/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus/sangueRESUMO
OBJECTIVES: Presepsin (PSEP: soluble CD14 subtype) is produced from bacteria-stimulated monocytes or neutrophils, thus recognized as a biomarker of sepsis. Aberrant functions in monocyte or neutrophils are increasingly recognized in systemic lupus erythematosus (SLE). We investigated whether plasma PSEP reflects disease activity in patients with SLE. METHODS: This retrospective study comprised 35 patients with SLE and 72 with non-SLE autoimmune diseases who visited our facility during the period from August 2012 to September 2015. Plasma PSEP levels and laboratory data were compared between SLE and non-SLE. Clinical markers of SLE disease activity, including SLE disease activity index 2000 (SLEDAI-2K), serum complement concentrations and serum anti-ds-DNA antibodies were assessed in correlation with plasma PSEP levels. RESULTS: Plasma PSEP levels in SLE were higher than those in non-SLE. This phenomenon holds true when comparing SLE and non-SLE patients in the absence of infection (p = .0008). Plasma PSEP levels in SLE patients negatively correlated with C3 (r = -0.4454, p = .0430), CH50 (r = -0.4502, p = .0406) and positively with SLEDAI-2K (r = 0.4801, p = .0237). CONCLUSION: Elevated plasma PSEP levels were correlated with disease activity of SLE, suggesting inappropriate monocyte or neutrophil activation in the pathophysiology of SLE exacerbation.
Assuntos
Receptores de Lipopolissacarídeos/sangue , Lúpus Eritematoso Sistêmico/sangue , Fragmentos de Peptídeos/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To evaluate the performance of the 2012 Systemic Lupus International Collaborating Clinics criteria (SLICC-12) on classifying systemic lupus erythematosus (SLE) in an uncontrolled multi-centered study with real-life scenario of the patients in Japan. METHODS: This study comprised 495 patients with SLE or non-SLE rheumatic diseases and allied conditions from 12 institutes in Japan. Chart review of each patient was performed by the 27 expert rheumatologists and diagnosis of 487 cases reached to the consensus. Value of the SLICC-12 on SLE classification was analyzed comparing with the 1997 revised American College of Rheumatology SLE classification criteria (ACR-97) employing the expert-consented diagnoses. RESULTS: Compared to the ACR-97, the SLICC-12 had a higher sensitivity (ACR-97 vs. SLICC-12: 0.88 vs. 0.99, p < .01) and comparable specificity (0.85 vs. 0.80). The rate of misclassification (0.14 vs. 0.11) or the area under the receiver operating characteristic curves (0.863 vs. 0.894) was not statistically different. In the cases that diagnoses corresponded in high rates among experts, both criteria showed high accordance of SLE classification over 85% with the expert diagnoses. CONCLUSION: Although employment of SLICC-12 for the classification for SLE should be carefully considered, the SLICC-12 showed the higher sensitivity on classifying SLE in Japanese population.
Assuntos
Lúpus Eritematoso Sistêmico/patologia , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Japão , Lúpus Eritematoso Sistêmico/classificação , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: Pulmonary arterial hypertension (PAH) associated with systemic sclerosis (SSc) has a poor prognosis compared to PAH associated with other connective tissue diseases (CTD). The objective of this study was to examine the difference in hemodynamic state between SSc-PAH and other CTD-PAH by performing cardiac magnetic resonance (CMR) imaging. METHODS: A single center retrospective analysis was conducted comprising 40 consecutive CTD patients who underwent right heart catheterization and CMR at the same period from January 2010 to October 2015. RESULTS: Thirty-two patients had pre-capillary pulmonary hypertension. Of these, 15 had SSc and 17 had other CTD. CMR measurements, particularly the ratio of right to left end-diastolic volume (RVEDV/LVEDV), correlated well with mean pulmonary arterial pressure (mPAP). Conversely, RVEDV/LVEDV and mPAP correlated differently in SSc and non-SSc patients. In SSc patients, the ratio of RVEDV/LVEDV to mPAP was significantly higher compared to non-SSc patients. In the follow-up study, 2 SSc patients exhibited increased RVEDV/LVEDV in spite of decreased mPAP following treatment. Kaplan-Meier analysis revealed poor prognosis of patients with increased RVEDV/LVEDV following treatment. CONCLUSIONS: Our data indicated that altered bi-ventricular interplay detected at CMR may represent SSc-related cardiac involvement and reflect poor prognosis of SSc-PAH.
Assuntos
Ventrículos do Coração/diagnóstico por imagem , Hipertensão Pulmonar/diagnóstico por imagem , Escleroderma Sistêmico/diagnóstico por imagem , Adulto , Idoso , Feminino , Seguimentos , Humanos , Hipertensão Pulmonar/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Escleroderma Sistêmico/complicaçõesRESUMO
OBJECTIVES: To evaluate the scoring of whole-body magnetic resonance imaging (WBMRI) for efficacy assessment in rheumatoid arthritis (RA) patients receiving biological disease-modifying anti-rheumatic drugs (bDMARDs). METHODS: Thirty consecutive RA patients receiving bDMARDs were included in this retrospective study. Contrast WBMRI was performed before and 1 year after bDMARDs initiation. RESULTS: At baseline, mean age was 57.1 years and mean disease duration was 3.0 years. Median disease activity score in 28 joints improved from 5.1 to 2.1. Treatment with bDMARDs improved mean whole-body synovitis score from 31.2 to 23.2 and median whole-body bone-edema score from 11 to 3. Whole-body bone-erosion score improved in seven patients and deteriorated in 17 patients. Logistic regression analysis identified whole-body synovitis score as a poor prognostic factor for whole-body bone-erosion progression. Bone-edema score in individual bones was identified as a poor prognostic factor for the progression of bone-erosion. Changes in hand synovitis score correlated with those of other joints, but neither changes in bone-edema nor erosion score of hands correlated with those of other joints in WBMRI. CONCLUSIONS: WBMRI scoring may be a novel useful tool to evaluate the efficacy of anti-rheumatic drugs, as well as a potential predictor of joint prognosis, in patients with RA.
Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Artrite Reumatoide/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos RetrospectivosRESUMO
OBJECTIVE: To investigate the prevalence and significance of the autoantibodies against complement component 1 q subcomponent (C1q) in patients with APS. METHODS: In all, 40 consecutive primary APS patients, 42 patients with non-SLE CTDs and 20 SLE patients negative for aPL were enrolled in this retrospective analysis. Refractory APS was defined as a clinical status of recurring thrombosis or pregnancy morbidity during adequate secondary prophylaxis. An ELISA was used to measure serum levels of anti-C1q antibodies and anaphylatoxins (C3a, C4a). RESULTS: Anti-C1q antibodies were found in 36% (15/42) and 2.5% (1/40) of primary APS patients and controls, respectively. Among primary APS patients, anti-C1q antibody titres were significantly correlated with serum C4a levels (P = 0.013). Neither the prevalence nor the titre of anti-C1q antibodies was associated with any specific clinical manifestations of APS, nor titres of aPL. Refractory APS patients (n = 10) had a higher prevalence of anti-C1q antibodies (9/10 vs 6/32, P = 0.01) than APS patients without recurrence (n = 32). CONCLUSION: Anti-C1q antibodies are associated with complement activation in APS and may contribute to the pathogenesis, particularly in refractory cases.
Assuntos
Anticorpos Antifosfolipídeos/fisiologia , Síndrome Antifosfolipídica/imunologia , Complemento C1q/imunologia , Trombose/imunologia , Adulto , Idoso de 80 Anos ou mais , Ativação do Complemento/fisiologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez/imunologia , Recidiva , Estudos Retrospectivos , Adulto JovemRESUMO
OBJECTIVE: Phosphatidylserine-dependent, also called aPS-PT, recognizes the phosphatidylserine-prothrombin complex, which is associated with APS. We have previously reported that aPS-PT induces tissue factor (TF) expression on monocytes through the p38 mitogen-activated protein kinase pathway. However, the cell surface interaction between prothrombin and aPS-PT, which is involved in the activation of cell-signalling pathways, has remained unknown. The objective of this study was to identify membrane proteins involved in the binding of prothrombin and aPS-PT to monocyte surfaces as well as the induction of TF expression. METHODS: RAW264.7 cells with FLAG-tagged prothrombin were incubated and separated using affinity chromatography with anti-FLAG antibody-conjugated Sepharose beads. Immunopurified proteins were then analysed by an online nano-liquid chromatography-tandem mass spectrometry. The binding between prothrombin and the identified protein, ribophorin II (RPN2), was analysed by ELISA and surface plasmon resonance. To elucidate the role of RPN2 in TF expression, the TF mRNA level in RAW264.7 cells treated with RPN2 small interfering RNA was determined by quantitative real-time PCR (qPCR). RESULTS: RPN2 was identified as a candidate molecule involved in the binding of prothrombin to the cell surface. The binding between prothrombin and RPN2 was confirmed by ELISA and surface plasmon resonance. RAW264.7 cells treated with RPN2 small interfering RNA showed significant reduction of the TF expression mediated by prothrombin and a mouse monoclonal aPS-PT. CONCLUSION: We identified that RPN2 is one of the prothrombin-binding proteins on monocyte surfaces, suggesting that RPN2 is involved in the pathophysiology of thrombosis in patients with APS.
Assuntos
Anticorpos Antifosfolipídeos/metabolismo , Proteínas de Membrana/metabolismo , Monócitos/metabolismo , Tromboplastina/metabolismo , Animais , Anticorpos Antifosfolipídeos/imunologia , Ensaio de Imunoadsorção Enzimática , Camundongos , Monócitos/imunologia , Fosfatidilserinas/metabolismo , Protrombina/imunologia , Células RAW 264.7 , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
Defective signaling or repair of DNA double-strand breaks has been associated with developmental defects and human diseases. The E3 ligase RING finger 168 (RNF168), mutated in the human radiosensitivity, immunodeficiency, dysmorphic features, and learning difficulties syndrome, was shown to ubiquitylate H2A-type histones, and this ubiquitylation was proposed to facilitate the recruitment of p53-binding protein 1 (53BP1) to the sites of DNA double-strand breaks. In contrast to more upstream proteins signaling DNA double-strand breaks (e.g., RNF8), deficiency of RNF168 fully prevents both the initial recruitment to and retention of 53BP1 at sites of DNA damage; however, the mechanism for this difference has remained unclear. Here, we identify mechanisms that regulate 53BP1 recruitment to the sites of DNA double-strand breaks and provide evidence that RNF168 plays a central role in the regulation of 53BP1 functions. RNF168 mediates K63-linked ubiquitylation of 53BP1 which is required for the initial recruitment of 53BP1 to sites of DNA double-strand breaks and for its function in DNA damage repair, checkpoint activation, and genomic integrity. Our findings highlight the multistep roles of RNF168 in signaling DNA damage.
Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia , Animais , Reparo do DNA/genética , Fibroblastos , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Camundongos , Proteína 1 de Ligação à Proteína Supressora de Tumor p53RESUMO
OBJECTIVE: Interstitial lung diseases (ILDs) complicated with PM or DM are frequently aggressive and refractory to treatment. Recently some reports have suggested the potential benefit of tacrolimus for severe ILD complicated with PM/DM. However, little evidence has yet shown the efficacy of tacrolimus in these settings. The aim of this study was to evaluate the efficacy of tacrolimus as a treatment for PM-/DM-related ILD. METHODS: This retrospective study comprised 49 previously untreated patients diagnosed as PM-/DM-related ILD admitted to Hokkaido University Hospital from January 2000 to July 2013. These patients were treated with tacrolimus plus conventional therapy or only with conventional therapy (prednisolone, i.v. CYC and/or ciclosporin). The primary endpoint was defined as the time to relapse or death of respiratory cause or a serious adverse event. The secondary endpoint was defined as the time from the initiation of immunosuppressive treatment to relapse or death of respiratory cause. Endpoints were compared by adjusted Cox regression model by using inverse probability of treatment weighting in order to reduce the impact of these selection biases and potential confounding factors. RESULTS: After adjustment, the tacrolimus group (n = 25) had significantly longer event-free survival as compared with the conventional therapy group (n = 24). The weighted hazard ratio (HR) was 0.32 (95% CI 0.14, 0.75, P = 0.008). In addition, the tacrolimus group had significantly longer disease-free survival as compared with the conventional therapy group. The weighted HR was 0.25 (95% CI 0.10, 0.66, P = 0.005). CONCLUSION: The addition of tacrolimus to conventional therapy significantly improved the prognosis of patients with PM-/DM-related ILD.
Assuntos
Dermatomiosite/complicações , Imunossupressores/uso terapêutico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/etiologia , Polimiosite/complicações , Tacrolimo/uso terapêutico , Adulto , Idoso , Determinação de Ponto Final , Feminino , Humanos , Japão , Doenças Pulmonares Intersticiais/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT) were strongly correlated with the presence of lupus anticoagulant showing a high specificity for the diagnosis of antiphospholipid syndrome. However, the main criticism for the clinical applicability of aPS/PT testing is the lack of reproducibility of the results among laboratories. In this study, we measured IgG and IgM aPS/PT using our original in-house enzyme-linked immunosorbent assays (ELISA) and commercial ELISA kits to assess the assay performance and to evaluate the accuracy of aPS/PT results. The study included 111 plasma samples collected from patients and stored at our laboratory for aPS/PT assessment. Sixty-one samples were tested for IgG aPS/PT using two assays: (1) aPS/PT in-house ELISA and (2) QUANTA Lite™ aPS/PT IgG ELISA kit (INOVA Diagnostics, Inc., USA). Fifty samples were evaluated for IgM aPS/PT using two assays: (1) aPS/PT in-house ELISA and (2) QUANTA Lite™ aPS/PT IgM ELISA kit (INOVA Diagnostics). Ninety-eight percent of samples yielded concordant results for IgG aPS/PT and 82 % for IgM aPS/PT. There was an excellent agreement between the IgG aPS/PT assays (Cohen κ = 0.962) and moderate agreement between the IgM aPS/PT assays (κ = 0.597). Statistically significant correlations in the aPS/PT results were obtained from both IgG and IgM aPS/PT assays (r = 0.749, r = 0.622, p < 0.001, respectively). In conclusion, IgG and IgM detection by ELISA is accurate. The performance of aPS/PT is reliable, and concordant results can be obtained using different ELISA methods.
Assuntos
Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Fosfatidilserinas/imunologia , Protrombina/imunologia , Adulto , Idoso , Síndrome Antifosfolipídica/sangue , Síndrome Antifosfolipídica/imunologia , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Controle de Qualidade , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Eukaryotic cells have evolved to use complex pathways for DNA damage signaling and repair to maintain genomic integrity. RNF168 is a novel E3 ligase that functions downstream of ATM,γ-H2A.X, MDC1, and RNF8. It has been shown to ubiquitylate histone H2A and to facilitate the recruitment of other DNA damage response proteins, including 53BP1, to sites of DNA break. In addition, RNF168 mutations have been causally linked to the human RIDDLE syndrome. In this study, we report that Rnf168(-/-) mice are immunodeficient and exhibit increased radiosensitivity. Rnf168(-/-) males suffer from impaired spermatogenesis in an age-dependent manner. Interestingly, in contrast to H2a.x(-/-), Mdc1(-/-), and Rnf8(-/-) cells, transient recruitment of 53bp1 to DNA double-strand breaks was abolished in Rnf168(-/-) cells. Remarkably, similar to 53bp1 inactivation, but different from H2a.x deficiency, inactivation of Rnf168 impairs long-range V(D)J recombination in thymocytes and results in long insertions at the class-switch junctions of B-cells. Loss of Rnf168 increases genomic instability and synergizes with p53 inactivation in promoting tumorigenesis. Our data reveal the important physiological functions of Rnf168 and support its role in both γ-H2a.x-Mdc1-Rnf8-dependent and -independent signaling pathways of DNA double-strand breaks. These results highlight a central role for RNF168 in the hierarchical network of DNA break signaling that maintains genomic integrity and suppresses cancer development in mammals.
Assuntos
Quebras de DNA de Cadeia Dupla , Instabilidade Genômica , Espermatogênese/genética , Ubiquitina-Proteína Ligases/genética , Fatores Etários , Animais , Proteínas Cromossômicas não Histona/metabolismo , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Feminino , Switching de Imunoglobulina/genética , Masculino , Camundongos , Camundongos Knockout , Camundongos Mutantes , Neoplasias/genética , Tolerância a Radiação , Recombinação Genética , Transdução de Sinais , Síndrome , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53 , Ubiquitina-Proteína Ligases/metabolismoRESUMO
TNF-α-converting enzyme (TACE) can cleave transmembrane proteins, such as TNF-α, TNF receptors, and epidermal growth factor receptor (EGFR) ligands, to release the extracellular domains from the cell surface. Recent studies have suggested that overexpression of TACE may be associated with the pathogenesis of inflammation and fibrosis. To determine the roles of TACE in inflammation and fibrosis, TACE transgenic (TACE-Tg) mice, which overexpressed TACE systemically, were generated. As the transgene-derived TACE was expressed as an inactive form, no spontaneous phenotype developed in TACE-Tg mice. However, the transgene-derived TACE could be converted to an active form by furin in vitro and by phorbol myristate acetate (PMA) in vivo. Subcutaneous injection of PMA into mice induced inflammatory cell infiltration 1 day later and subsequent dermal fibrosis 7 days later. Interestingly, the degree of dermal fibrosis at day 7 was significantly higher in TACE-Tg mice than in wild-type mice. Correspondingly, PMA increased the expression of type I collagen in the primary culture of dermal fibroblasts derived from TACE-Tg mice. Furthermore, phosphorylated EGFR was increased in the fibroblasts by the PMA treatment. The collective findings suggest that TACE overexpression and activation in fibroblasts could shed off putative EGFR ligands. Subsequently, the soluble EGFR ligands could bind and activate EGFR on fibroblasts, and then increase the type I collagen expression resulting in induction of dermal fibrosis. These results also suggest that TACE and EGFR on fibroblasts may be novel therapeutic targets of dermal fibrosis, which is induced after diverse inflammatory disorders of the skin.