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1.
Swiss Med Wkly ; 154: 3407, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38875461

RESUMO

Patients with inflammatory bowel disease (IBD) are prone to reduced bone mineral density and elevated overall fracture risk. Osteopenia affects up to 40% of patients with IBD (high regional variability). Besides disease activity, IBD specialists must consider possible side effects of medication and the presence of associated diseases and extraintestinal manifestations. Osteopenia and osteoporosis remain frequent problems in patients with IBD and are often underestimated because of widely differing screening and treatment practices. Malnutrition, chronic intestinal inflammation and corticosteroid intake are the major pathophysiological factors contributing to osteoporosis. Patients with IBD are screened for osteoporosis using dual-energy X-ray absorptiometry (DXA), which is recommended for all patients with a prolonged disease course of more than three months, with repeated corticosteroid administration, aged >40 years with a high FRAX risk score or aged <40 years with multiple risk factors. From a therapeutic perspective, besides good disease control, vitamin D supplementation and glucocorticoid sparing, several specific osteological options are available: bisphosphonates, receptor activator of nuclear factor kappa-B ligand (RANKL) inhibitors (denosumab), parathyroid hormone (PTH) analogues and selective estrogen receptor modulators. This review provides an overview of the pathophysiology, diagnosis, prevention and treatment of IBD-associated bone loss.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Doenças Ósseas Metabólicas , Doenças Inflamatórias Intestinais , Osteoporose , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/fisiopatologia , Osteoporose/etiologia , Doenças Ósseas Metabólicas/etiologia , Fatores de Risco , Vitamina D/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico
2.
PLoS One ; 18(4): e0281585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37018188

RESUMO

BACKGROUND: Despite the widespread use of glucocorticoids in inflammatory and autoimmune disorders, there is uncertainty about the safe cessation of long-term systemic treatment, as data from prospective trials are largely missing. Due to potential disease relapse or glucocorticoid-induced hypocortisolism, the drug is often tapered to sub-physiological doses rather than stopped when the underlying disease is clinically stable, increasing the cumulative drug exposure. Conversely, the duration of exposure to glucocorticoids should be minimized to lower the risk of side effects. METHODS: We designed a multicenter, randomized, triple-blinded, placebo-controlled trial to test the clinical noninferiority of abrupt glucocorticoid stop compared to tapering after ≥28 treatment days with ≥420 mg cumulative and ≥7.5 mg mean daily prednisone-equivalent dose. 573 adult patients treated systemically for various disorders will be included after their underlying disease has been stabilized. Prednisone in tapering doses or matching placebo is administered over 4 weeks. A 250 mg ACTH-test, the result of which will be revealed a posteriori, is performed at study inclusion; all patients are instructed on glucocorticoid stress cover dosing. Follow-up is for 6 months. The composite primary outcome measure is time to hospitalization, death, initiation of unplanned systemic glucocorticoid therapy, or adrenal crisis. Secondary outcomes include the individual components of the primary outcome, cumulative glucocorticoid doses, signs and symptoms of hypocortisolism, and the performance of the ACTH test in predicting the clinical outcome. Cox proportional hazard, linear, and logistic regression models will be used for statistical analysis. CONCLUSION: This trial aims to demonstrate the clinical noninferiority and safety of abrupt treatment cessation after ≥28 days of systemic glucocorticoid therapy in patients with stabilized underlying disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03153527; EUDRA-CT: 2020-005601-48 https://clinicaltrials.gov/ct2/show/NCT03153527?term=NCT03153527&draw=2&rank=1.


Assuntos
Insuficiência Adrenal , Glucocorticoides , Adulto , Humanos , Insuficiência Adrenal/induzido quimicamente , Hormônio Adrenocorticotrópico , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Estudos Multicêntricos como Assunto , Recidiva Local de Neoplasia/tratamento farmacológico , Prednisona/efeitos adversos , Prednisona/uso terapêutico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Suspensão de Tratamento
3.
Lancet Rheumatol ; 3(11): e789-e797, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34514436

RESUMO

BACKGROUND: B-cell-depleting therapies increase the risk of morbidity and mortality due to COVID-19. Evidence-based SARS-CoV-2 vaccination strategies for patients on B-cell-depleting therapies are scarce. We aimed to investigate humoral and cell-mediated immune responses to SARS-CoV-2 mRNA-based vaccines in patients receiving CD20-targeted B-cell-depleting agents for autoimmune disease, malignancy, or transplantation. METHODS: The RituxiVac study was an investigator-initiated, single-centre, open-label study done at the Bern University Hospital (Bern, Switzerland). Patients with a treatment history of anti-CD20-depleting agents (rituximab or ocrelizumab) and with no previous history of SARS-CoV-2 infection were enrolled between April 26 and June 30, 2021, for analysis of humoral and cell-mediated immune responses (by interferon-γ [IFNγ] release assay) at least 4 weeks after completing vaccination against SARS-CoV-2. Healthy controls without a history of SARS-CoV-2 infection were also enrolled at least 4 weeks after completing vaccination against SARS-CoV-2. All study participants received two doses of either the Pfizer-BioNTech BNT162b2 vaccine or the Moderna mRNA-1273 vaccine. The primary outcome was the proportion of patients with a history of anti-CD20 treatment who showed a humoral immune response against the SARS-CoV-2 spike protein in comparison with immunocompetent controls. Prespecified secondary endpoints were the effect of anti-CD20 therapy (including time since last treatment and cumulative dose) on humoral or cell-mediated immune responses to SARS-CoV-2 vaccination, and biomarkers of immunocompetence. This study is registered with ClinicalTrials.gov, NCT04877496. FINDINGS: The final study population comprised 96 patients and 29 immunocompetent controls. The median age of patients was 67 years (IQR 57-72) and of controls was 54 years (45-62), and 51 (53%) of 96 patients and 19 (66%) of 29 controls were female. The median time since last anti-CD20 treatment was 1·07 years (IQR 0·48-2·55) and the median cumulative dose of an anti-CD20 depleting agent was 2·80 g (1·50-5·00). Anti-spike IgG antibodies were detected in 47 (49%) of 96 patients 1·79 months (IQR 1·16-2·48) after the second vaccine dose compared to 29 (100%) of 29 controls 1·81 months (1·17-2·48) after the second vaccine dose (p<0·001). SARS-CoV-2-specific IFNγ release was detected in 13 (20%) of 66 patients and 21 (75%) of 28 of healthy controls (p<0·001). Only nine (14%) of 66 patients were double positive for anti-SARS-CoV-2 spike IgG and cell-mediated responses, compared with 21 (75%) of 28 healthy controls (p<0·001). Time since last anti-CD20 therapy (>7·6 months; positive predictive value 0·78), peripheral CD19+ cell count (>27 cells per µL; positive predictive value 0·70), and CD4+ lymphocyte count (>653 cells per µL; positive predictive value 0·71) were predictive of humoral vaccine response (area under the curve [AUC] 67% [95% CI 56-78] for time since last anti-CD20 therapy, 67% [55-80] for peripheral CD19+ count, and 66% [54-79] for CD4+ count). INTERPRETATION: This study provides further evidence of blunted humoral and cell-mediated immune responses elicited by SARS-CoV-2 mRNA vaccines in patients with a history of CD20 B-cell-depleting treatment. Lymphocyte subpopulation counts were associated with vaccine response in this highly vulnerable population. On validation, these results could help guide both the administration of SARS-CoV-2 vaccines and B-cell-depleting agents in this population. FUNDING: Bern University Hospital.

4.
J Clin Endocrinol Metab ; 105(1)2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31702015

RESUMO

CONTEXT: Both thyroid dysfunction and levothyroxine (LT4) therapy have been associated with bone loss, but studies on the effect of LT4 for subclinical hypothyroidism (SHypo) on bone yielded conflicting results. OBJECTIVE: To assess the effect of LT4 treatment on bone mineral density (BMD), Trabecular Bone Score (TBS), and bone turnover markers (BTMs) in older adults with SHypo. DESIGN AND INTERVENTION: Planned nested substudy of the double-blind placebo-controlled TRUST trial. Participants with SHypo were randomized to LT4 with dose titration versus placebo with computerized mock titration. SETTING AND PARTICIPANTS: 196 community-dwelling adults over 65 years enrolled at the Swiss TRUST sites had baseline and 1-year follow-up bone examinations; 4 participants withdrew due to adverse events not related to treatment. MAIN OUTCOME MEASURES: One-year percentage changes of BMD, TBS, and 2 serum BTMs (serum CTX-1 [sCTX] and procollagen type 1 N-terminal polypeptide [P1NP]). Student's t-test for unadjusted analyses and linear regression adjusted for clinical center and sex were performed. RESULTS: Mean age was 74.3 years ± 5.7, 45.4% were women, and 19.6% were osteoporotic. The unadjusted 1-year change in lumbar spine BMD was similar between LT4 (+0.8%) and placebo-treated groups (-0.6%; between-groups difference +1.4%: 95% confidence interval [CI] -0.1 to 2.9, P = .059). Likewise, there were no between-group differences in 1-year change in TBS (-1.3%: 95% CI -3.1 to 0.6, P = .19), total hip BMD (-0.2%: 95% CI -1.1 to 0.1, P = .61), or BTMs levels (sCTX +24.1%: 95% CI -7.9 to 56.2, P = .14), or after adjustment for clinical centers and sex. CONCLUSIONS: Over 1-year levothyroxine had no effect on bone health in older adults with SHypo. REGISTRATION: ClinicalTrial.gov NCT01660126 and NCT02491008.


Assuntos
Osso e Ossos/efeitos dos fármacos , Hipotireoidismo/tratamento farmacológico , Tiroxina/uso terapêutico , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/fisiologia , Método Duplo-Cego , Feminino , Terapia de Reposição Hormonal , Humanos , Hipotireoidismo/epidemiologia , Hipotireoidismo/metabolismo , Masculino , Osteoporose/prevenção & controle , Suíça/epidemiologia , Tiroxina/farmacologia
5.
Br J Haematol ; 186(1): 101-112, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30941747

RESUMO

Anaemia affects quality of life and radiographic outcome in rheumatoid arthritis (RA). In a cross-sectional study with 779 patients, we assessed the prognostic potential of the major haematopoietic regulators, hepcidin and erythropoietin, comparing their serum concentrations with respect to different anaemia types, inflammatory activity, anti-cytokine-specific treatment effects and iron deficiency (ID) indices. The results showed that clinical disease activity was more closely associated with haemoglobin levels than with anti-tumour necrosis factor-alpha or interleukin 6 receptor effects. In ID, hepcidin was suppressed, independently of inflammation. Erythropoietin levels were inappropriately low in relation to the degree of anaemia, but, in contrast to low haemoglobin, not directly associated with joint damage progression. Hepcidin and erythropoietin levels are intimately connected with inflammation and ID. Interventional studies on these important targets are already in progress.


Assuntos
Anemia Ferropriva/sangue , Artrite Reumatoide/patologia , Eritropoetina/sangue , Hepcidinas/sangue , Inflamação/sangue , Adulto , Anemia Ferropriva/etiologia , Artrite Reumatoide/sangue , Estudos Transversais , Progressão da Doença , Feminino , Hemoglobinas/análise , Humanos , Inflamação/etiologia , Articulações/patologia , Masculino , Pessoa de Meia-Idade
6.
Bone ; 107: 56-65, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29081378

RESUMO

Bone protective effects of TNFα inhibition in rheumatoid arthritis are thought to be mediated by inhibiting synovial osteoclast differentiation and activity. However, it has not been addressed, if TNFα inhibitors alter the pool of peripheral osteoclast precursor cells (OPCs). Here, we blocked TNFα function in C57BL/6 mice with antigen induced arthritis (AIA) using the soluble TNFα receptor etanercept. Synovial bone lesions and osteoclasts were markedly reduced upon Etanercept in the early chronic phase of AIA. Unexpectedly this was not associated with a reduced recruitment of circulating OPCs to the arthritic joint nor to reduced synovial inflammation. In contrast we found that OPC numbers in bone marrow and blood were significantly reduced. Overall our study suggests that arrest of osteoclast mediated bone lesions upon inhibition of TNFα is, at least initially, based on reduced OPC availability in the periphery, and not on OPC recruitment or local anti-inflammatory effects in the arthritic joint.


Assuntos
Antirreumáticos/farmacologia , Artrite Reumatoide/patologia , Osteoclastos/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Artrite Experimental/patologia , Células da Medula Óssea/efeitos dos fármacos , Etanercepte/farmacologia , Camundongos , Camundongos Endogâmicos C57BL
7.
Swiss Med Wkly ; 147: w14529, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29120020

RESUMO

Multicentric carpotarsal osteolysis (MCTO) is an autosomal dominant disease of the skeleton characterised by progressive destruction of carpal and tarsal bones. Recently, it has been demonstrated that this disease is caused by heterozygous mutations in the gene for the transcriptional repressor MAFB. We analysed genomic DNA and RNA from leucocytes of a female patient diagnosed with MCTO. We identified the mutation c.161C>T in the genomic sequence and in the expressed messenger RNA for MAFB. This is the second report of the c.161C>T mutation in a MCTO patient. Since the parents do not possess this mutation, the daughter must have acquired a de novo mutation. At the level of the gene, this mutation is found at a CpG dinucleotide sequence, suggesting that DNA methylation was involved in the occurrence of the DNA aberration. At the level of the protein, the mutation exchanges a serine with a leucine residue at a position on MAFB that can become phosphorylated in the wild-type protein. MAFB negatively regulates the RANKL-dependent differentiation of monocytes into osteoclasts. It is likely that the mutation will affect the phosphorylation status of the protein and its biological activity. When the activity of the transcriptional repressor is reduced, osteoclastogenesis will be increased, which might explain the carpotarsal bone destruction observed in the patient.


Assuntos
Fator de Transcrição MafB/genética , Mutação/genética , Osteólise/diagnóstico , Ossos do Carpo , Feminino , Heterozigoto , Humanos , Ligante RANK , Ossos do Tarso , Adulto Jovem
8.
Bone ; 97: 267-277, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28161590

RESUMO

Levels of circulating cytokines are elevated in inflammatory diseases. Previously, it was shown that interleukin (IL-)17A, in synergism with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and tumor necrosis factor α (TNFα), induces the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) by murine osteoblasts in vitro. In this study, we further analyzed the effects of GM-CSF on osteoclast development in vitro. The effects of IL-17A, TNFα, and 1,25(OH)2D3 on the regulation of osteoclast development were investigated in cocultures of bone marrow-derived osteoclast progenitor cells (OPC) and mouse calvarial osteoblasts. Additionally, OPC were grown for 3days in media containing macrophage colony-stimulating factor (M-CSF), GM-CSF, or M-CSF/GM-CSF. Subsequently, the osteoclastogenic potential and the capacity to dissolve amorphous calcium phosphate were assessed in each of the three populations of OPC. IL-17A, in synergism with TNFα and 1,25(OH)2D3, inhibited the development of osteoclasts in cocultures by stimulating the osteoblast lineage cells to release GM-CSF. GM-CSF-treated OPC expressed traits characteristic of dendritic cells. Upon removal of GM-CSF and supplementation of the culture media with M-CSF/RANKL, the cells lost their dendritic cell characteristics and differentiated into osteoclasts. OPC pretreated with GM-CSF and M-CSF/GM-CSF exhibited delayed development to osteoclasts and an extended proliferation phase. Elevated levels of GM-CSF in systemic inflammatory diseases may cause an expansion of the OPC pools in the bone, bone marrow, and blood. Upon homing to the bone, this may lead to an increase in the number of osteoclasts and in bone resorption.


Assuntos
Antígeno CD11c/metabolismo , Diferenciação Celular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Osteoclastos/citologia , Osteoclastos/metabolismo , Animais , Fosfatos de Cálcio/farmacologia , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-17/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/citologia , Camundongos Endogâmicos C57BL , Monócitos/citologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fenótipo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
9.
RMD Open ; 2(1): e000079, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26819749

RESUMO

OBJECTIVE: To investigate the regulatory effect of tumour necrosis factor (TNF) blockade with infliximab on the distribution of peripheral blood monocyte subpopulations in patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). METHODS: Purified CD11b+CD14+ monocytes from 5 patients with RA and 5 AS were analysed ex vivo before and after infliximab treatment by flow cytometry for CD16, CD163, CD11b, C-C chemokine receptor type 2 (CCR2) and CXC chemokine receptor 4 (CXCR4) at baseline and at days 2, 14, 84 and 168 after the first infliximab administration. Serum levels of the stromal cell-derived factor (SDF)-1 and monocyte chemotactic peptide (MCP)-1 at different time points were measured in either patient group before and on infliximab treatment. RESULTS: Anti-TNF treatment with infliximab led to a significant increase of circulating CD11b+ non-classical and a concomitantly decrease of CD11b+ classical monocytes, to a decline in SDF-1 levels and reduced expression of CCR2 and CXCR4 on non-classical monocyte subpopulation. CONCLUSIONS: Our study shows, that TNFα blockade by infliximab resulted in a dichotomy of the regulation of classical and non-classical monocytes that might have substantial impact on inhibition of osteoclastogenesis and of subsequent juxta-articular bone destruction and systemic bone loss in RA and AS.

10.
Arthritis Rheum ; 65(2): 436-46, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23124514

RESUMO

OBJECTIVE: To investigate the effects of interleukin-17A (IL-17A) on osteoclastogenesis in vitro. METHODS: Bone marrow cells (BMCs) were isolated from the excised tibia and femora of wild-type C57BL/6J mice, and osteoblasts were obtained by sequential digestion of the calvariae of ddY, C57BL/6J, and granulocyte-macrophage colony-stimulating factor-knockout (GM-CSF(-/-)) mice. Monocultures of BMCs or cocultures of BMCs and osteoblasts were supplemented with or without 1,25-dihydroxyvitamin D(3)(1,25[OH](2)D(3)), recombinant human macrophage colony-stimulating factor (M-CSF), RANKL, and IL-17A. After 5-6 days, the cultures were fixed with 4% paraformaldehyde and subsequently stained for the osteoclast marker enzyme tartrate-resistant acid phosphatase (TRAP). Osteoprotegerin (OPG) and GM-CSF expression were measured by enzyme-linked immunosorbent assay, and transcripts for RANK and RANKL were detected by real-time polymerase chain reaction. RESULTS: In both culture systems, IL-17A alone did not affect the development of osteoclasts. However, the addition of IL-17A plus 1,25(OH)(2)D(3) to cocultures inhibited early osteoclast development within the first 3 days of culture and induced release of GM-CSF into the culture supernatants. Furthermore, in cocultures of GM-CSF(-/-) mouse osteoblasts and wild-type mouse BMCs, IL-17A did not affect osteoclast development, corroborating the role of GM-CSF as the mediator of the observed inhibition of osteoclastogenesis by IL-17A. CONCLUSION: These findings suggest that IL-17A interferes with the differentiation of osteoclast precursors by inducing the release of GM-CSF from osteoblasts.


Assuntos
Calcitriol/farmacologia , Diferenciação Celular/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-17/farmacologia , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Animais , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoprotegerina/metabolismo
12.
J Immunol ; 183(2): 1435-45, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19553536

RESUMO

Annexin-1 (ANXA1) is a mediator of the anti-inflammatory actions of endogenous and exogenous glucocorticoids (GC). The mechanism of ANXA1 effects on cytokine production in macrophages is unknown and is here investigated in vivo and in vitro. In response to LPS administration, ANXA1(-/-) mice exhibited significantly increased serum IL-6 and TNF compared with wild-type (WT) controls. Similarly, LPS-induced IL-6 and TNF were significantly greater in ANXA1(-/-) than in WT peritoneal macrophages in vitro. In addition, deficiency of ANXA1 was associated with impairment of the inhibitory effects of dexamethasone (DEX) on LPS-induced IL-6 and TNF in macrophages. Increased LPS-induced cytokine expression in the absence of ANXA1 was accompanied by significantly increased LPS-induced activation of ERK and JNK MAPK and was abrogated by inhibition of either of these pathways. No differences in GC effects on MAPK or MAPK phosphatase 1 were observed in ANXA1(-/-) cells. In contrast, GC-induced expression of the regulatory protein GILZ was significantly reduced in ANXA1(-/-) cells by silencing of ANXA1 in WT cells and in macrophages of ANXA1(-/-) mice in vivo. GC-induced GILZ expression and GC inhibition of NF-kappaB activation were restored by expression of ANXA1 in ANXA1(-/-) cells, and GILZ overexpression in ANXA1(-/-) macrophages reduced ERK MAPK phosphorylation and restored sensitivity of cytokine expression and NF-kappaB activation to GC. These data confirm ANXA1 as a key inhibitor of macrophage cytokine expression and identify GILZ as a previously unrecognized mechanism of the anti-inflammatory effects of ANXA1.


Assuntos
Anexina A1/fisiologia , Interleucina-6/biossíntese , Fatores de Transcrição/biossíntese , Fator de Necrose Tumoral alfa/biossíntese , Animais , Citocinas/biossíntese , Regulação da Expressão Gênica , Glucocorticoides/farmacologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Transdução de Sinais
13.
Arthritis Res Ther ; 11(3): R62, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19419560

RESUMO

INTRODUCTION: Reconstitution of peripheral blood (PB) B cells after therapeutic depletion with the chimeric anti-CD20 antibody rituximab (RTX) mimics lymphatic ontogeny. In this situation, the repletion kinetics and migratory properties of distinct developmental B-cell stages and their correlation to disease activity might facilitate our understanding of innate and adaptive B-cell functions in rheumatoid arthritis (RA). METHODS: Thirty-five 'RTX-naïve' RA patients with active arthritis were treated after failure of tumour necrosis factor blockade in an open-label study with two infusions of 1,000 mg RTX. Prednisone dose was tapered according to clinical improvement from a median of 10 mg at baseline to 5 mg at 9 and 12 months. Conventional disease-modifying antirheumatic drugs were kept stable. Subsets of CD19+ B cells were assessed by flow cytometry according to their IgD and CD27 surface expression. Their absolute number and relative frequency in PB were followed every 3 months and were determined in parallel in synovial tissue (n = 3) or synovial fluid (n = 3) in the case of florid arthritis. RESULTS: Six of 35 patients fulfilled the European League Against Rheumatism criteria for moderate clinical response, and 19 others for good clinical response. All PB B-cell fractions decreased significantly in number (P < 0.001) after the first infusion. Disease activity developed independently of the total B-cell number. B-cell repopulation was dominated in quantity by CD27-IgD+ 'naïve' B cells. The low number of CD27+IgD- class-switched memory B cells (MemB) in the blood, together with sustained reduction of rheumatoid factor serum concentrations, correlated with good clinical response. Class-switched MemB were found accumulated in flaring joints. CONCLUSIONS: The present data support the hypothesis that control of adaptive immune processes involving germinal centre-derived, antigen, and T-cell-dependently matured B cells is essential for successful RTX treatment.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Linfócitos B/citologia , Linfócitos B/imunologia , Switching de Imunoglobulina/imunologia , Imunoglobulinas/classificação , Depleção Linfocítica , Linfócitos B/classificação , Contagem de Células/métodos , Separação Celular/métodos , Feminino , Citometria de Fluxo/métodos , Humanos , Imunoglobulinas/biossíntese , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
15.
J Immunol ; 177(11): 8148-53, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17114490

RESUMO

Annexin 1 (Anx-1) is a mediator of the anti-inflammatory actions of glucocorticoids, but the mechanism of its anti-inflammatory effects is not known. We investigated the role of Anx-1 in the regulation of the proinflammatory cytokine, IL-6. Lung fibroblast cell lines derived from Anx-1(-/-) and wild-type (WT) mice were treated with dexamethasone and/or IL-1. IL-6 mRNA and protein were measured using real-time PCR and ELISA, and MAPK pathway activation was studied. Compared with WT cells, unstimulated Anx-1(-/-) cells exhibited dramatically increased basal IL-6 mRNA and protein expression. In concert with this result, Anx-1 deficiency was associated with increased basal phosphorylated p38, JNK, and ERK1/2 MAPKs. IL-1-inducible phosphorylated p38 was also increased in Anx-1(-/-) cells. The increase in IL-6 release in Anx-1(-/-) cells was inhibited by inhibition of p38 MAPK. Anx-1(-/-) cells were less sensitive to dexamethasone inhibition of IL-6 mRNA expression than WT cells, although inhibition by dexamethasone of IL-6 protein was similar. MAPK phosphatase-1 (MKP-1), a glucocorticoid-induced negative regulator of MAPK activation, was up-regulated by dexamethasone in WT cells, but this effect of dexamethasone was significantly impaired in Anx-1(-/-) cells. Treatment of Anx-1(-/-) cells with Anx-1 N-terminal peptide restored MKP-1 expression and inhibited p38 MAPK activity. These data demonstrate that Anx-1 is an endogenous inhibitory regulator of MAPK activation and IL-6 expression, and that Anx-1 is required for glucocorticoid up-regulation of MKP-1. Therapeutic manipulation of Anx-1 could provide glucocorticoid-mimicking effects in inflammatory disease.


Assuntos
Anexina A1/metabolismo , Fibroblastos/metabolismo , Interleucina-6/biossíntese , Transdução de Sinais/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Anexina A1/imunologia , Anti-Inflamatórios/farmacologia , Western Blotting , Linhagem Celular , Dexametasona/farmacologia , Fosfatase 1 de Especificidade Dupla , Ativação Enzimática/fisiologia , Ensaio de Imunoadsorção Enzimática , Fibroblastos/imunologia , Expressão Gênica , Camundongos , Proteína Fosfatase 1 , Proteínas Tirosina Fosfatases/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
J Immunol ; 177(7): 4818-25, 2006 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16982923

RESUMO

Macrophage migration inhibitory factor (MIF) has a key role in regulation of innate and adaptive immunity and is implicated in sepsis, tumorigenesis, and autoimmune disease. MIF deficiency or immunoneutralization leads to protection against fatal endotoxic, exotoxic, and infective shock, and anti-inflammatory effects in other experimental models of inflammatory disease. We report a novel regulatory role of MIF in type 1 IL-1R and p55 TNFR expression and function. Compared with wild-type cells, MIF-deficient cells were hyporesponsive to IL-1- and TNF-induced MAPK activity, AP-1 activity, and cellular proliferation, while NF-kappaB function was preserved. Hyporesponsiveness of MIF-deficient cells was associated with down-regulation of cytokine receptor expression, which was restored by reconstitution of either an upstream kinase of MAPK, MAPK/ERK kinase, or MIF. These data suggest that endogenous MIF is required for cytokine activation of MAPK/AP-1 and cytokine receptor expression. This autocrine regulatory pathway defines an important amplifying role of endogenous MIF in cytokine-mediated immune and inflammatory diseases and provides further molecular evidence for the critical role of MIF in cellular activation.


Assuntos
Fibroblastos/imunologia , Interleucina-1/metabolismo , Fatores Inibidores da Migração de Macrófagos/imunologia , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Western Blotting , Proliferação de Células , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática/imunologia , Ensaio de Imunoadsorção Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/metabolismo , Citometria de Fluxo , Interleucina-6/biossíntese , Fatores Inibidores da Migração de Macrófagos/deficiência , Camundongos , NF-kappa B/metabolismo , Receptores de Citocinas/metabolismo , Receptores de Interleucina-1/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição AP-1/metabolismo
17.
FEBS Lett ; 580(3): 974-81, 2006 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-16442105

RESUMO

The pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) is induced by glucocorticoids (GCs), but it was not previously known if MIF regulates cellular sensitivity to GC. Here we show in GC and LPS-treated peritoneal macrophages derived from MIF-/- and wt mice that the absence of endogenous MIF is associated with increased sensitivity to GC of TNF release. This is associated with increased expression of mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1), concomitant decreased phosphorylation of p38 MAPK, but no effect of MIF on nuclear factor kappaB (NF-kappaB). These results demonstrate that MIF regulates GC sensitivity by phosphorylation of p38, and provides a cellular mechanism for this observation, indicating that MKP-1 is a central target of this regulation.


Assuntos
Anti-Inflamatórios/farmacologia , Dexametasona/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fatores Inibidores da Migração de Macrófagos/metabolismo , Macrófagos Peritoneais/fisiologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Fosfatase 1 de Especificidade Dupla , Proteínas Imediatamente Precoces/metabolismo , Oxirredutases Intramoleculares , Sistema de Sinalização das MAP Quinases/fisiologia , Fatores Inibidores da Migração de Macrófagos/deficiência , Macrófagos Peritoneais/citologia , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 1 , Processamento de Proteína Pós-Traducional/fisiologia , Proteínas Tirosina Fosfatases/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Swiss Med Wkly ; 132(29-30): 414-22, 2002 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-12428187

RESUMO

OBJECTIVE: To examine the potential of the two tumour necrosis factor (TNF) inhibitors infliximab and etanercept as remission-inducing agents in chronic therapy-resistant inflammatory disorders of immune or non-immune pathogenesis. METHODS: 14 patients with adult Still's disease/macrophage activation syndrome (4), Wegener's disease (3), Behçet's disease (3), keratoscleritis (1), lymphomatous tracheo-bronchitis (1) Cogan's syndrome (1), and rapidly destructive crystal arthropathy (1) were treated with infliximab (n = 10) and etanercept (n = 4). All patients showed organ-threatening progression of their diseases with resistance to conventional immunosuppressive medication. Therapeutic benefit was assessed clinically and by documenting organ-specific functional and morphological alterations. Side effects were compared with the data of our clinic's rheumatoid arthritis (RA) patients treated by TNF inhibitors. RESULTS: A rapid and dramatic beneficial effect was documented in 9 patients and a moderate one in 5. Best responses (clinical and laboratory parameters) were seen in patients with macrophage activation syndrome/adult Still's disease and Behçet's disease, while the results were less impressive in those with Wegener's disease, Cogan's syndrome, idiopathic cerato-scleritis and lymphomatous tracheobronchitis. In all cases immunosuppressive agents and systemic glucocorticoids could be reduced or discontinued. CONCLUSIONS: TNF inhibition may be highly effective in patients with severe, therapy-resistant chronic inflammatory disorders.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite/tratamento farmacológico , Doenças Autoimunes/tratamento farmacológico , Síndrome de Behçet/tratamento farmacológico , Bronquite Crônica/tratamento farmacológico , Granulomatose com Poliangiite/tratamento farmacológico , Imunoglobulina G/uso terapêutico , Ceratose/tratamento farmacológico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Esclerite/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Doença de Still de Início Tardio/tratamento farmacológico , Traqueíte/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Artrite/diagnóstico por imagem , Artrite/fisiopatologia , Doenças Autoimunes/diagnóstico por imagem , Doenças Autoimunes/fisiopatologia , Síndrome de Behçet/diagnóstico por imagem , Síndrome de Behçet/fisiopatologia , Bronquite Crônica/diagnóstico por imagem , Bronquite Crônica/fisiopatologia , Doença Crônica , Etanercepte , Feminino , Granulomatose com Poliangiite/diagnóstico por imagem , Granulomatose com Poliangiite/fisiopatologia , Humanos , Infliximab , Ceratose/diagnóstico por imagem , Ceratose/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radiografia , Indução de Remissão , Esclerite/diagnóstico por imagem , Esclerite/fisiopatologia , Transdução de Sinais/fisiologia , Doença de Still de Início Tardio/diagnóstico por imagem , Doença de Still de Início Tardio/fisiopatologia , Síndrome , Traqueíte/diagnóstico por imagem , Traqueíte/fisiopatologia
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