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1.
BMC Med ; 21(1): 55, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36782189

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory disease that is associated with joint pain and stiffness. Biologics represent some of the most effective treatments for RA, but previous guidance from the National Institute for Health and Care Excellence (NICE) has limited their use to patients with severely active disease. This has meant patients with moderately active RA have been treated as if they have an acceptable disease state, despite many cases where the inflammation has a major impact on joint damage, mobility, pain and quality of life. However, recent guideline changes (NICE TA715) have approved the use of three biologics - adalimumab, etanercept and infliximab - for the treatment of moderately active RA. MAIN BODY: In response to these changes, we have held discussions with medical teams from across the UK to consider the main implications for implementation of these new recommendations, as well as any differences in approach that may exist at a local level. Several key challenges were identified. These included establishing methods of educating both physicians and patients concerning the new availability of the biologic treatments, with suggestions of various organisations that could be approached to circulate informative material. Identifying which patients with moderately active RA stand to benefit was another discussion topic. Relying solely on scoring systems like Disease Activity Score in 28 Joints (DAS28) was acknowledged to have limitations, and alternative complementary approaches such as ultrasound, as well as assessing a patient's co-morbidities, could also be useful tools in determining those who could benefit from biologics. An additional challenge for the process of patient identification has been the increase in the use of telemedicine consultations in response to the coronavirus disease 2019 (COVID-19) pandemic. More use of patient-reported outcomes was raised as one possible solution, and the importance of maintaining up-to-date databases on patient disease scores and treatment history was also stressed. CONCLUSION: While challenges exist in education and identifying patients who may benefit from the use of biologics, the NICE TA715 recommendations hold great potential in addressing an unmet need for the treatment of moderate RA.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , COVID-19 , Humanos , Antirreumáticos/uso terapêutico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Qualidade de Vida , Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/uso terapêutico
2.
Rheumatology (Oxford) ; 61(2): 787-793, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33944915

RESUMO

OBJECTIVES: To determine whether concomitant HCQ modulates the increase in erythrocyte mean corpuscular volume (MCV) caused by MTX therapy, and whether this is associated with improved clinical response in RA. METHODS: A retrospective observational analysis was conducted on two independent hospital datasets of biologic-naïve, early-RA patients who started oral MTX. Baseline characteristics, DAS28-ESR and monthly MCV after starting MTX were obtained. Conventional and machine-learning statistical approaches were applied to the discovery cohort (Cohort 1, 655 patients) and results validated using Cohort 2 (225 patients). RESULTS: HCQ therapy with MTX was associated with a 2-fold increase in the likelihood of response defined in this study as clinical remission or low disease activity at 6 months (P <0.001). The improved clinical outcome of combination HCQ and MTX therapy was associated with an accelerated rise in MCV from 2 months after commencing therapy. The increase in MCV at 3 months was equivalent to the contemporaneous reduction in the DAS (DAS28-ESR) in predicting clinical response at 6 months. Using latent class mixed modelling, five trajectories of MCV change over 6 months from baseline were identified. The odds ratio of response to treatment was 16.2 (95% CI 5.7, 46.4, P <0.001) in those receiving combination therapy classified within the MCV elevation >5 fl class, which contained the most patients, compared with MTX alone. CONCLUSION: Our data provide mechanistic insight into the synergistic clinical benefit of concomitant HCQ with MTX, boosting the rise in MCV, which could serve as a companion biomarker of treatment response.


Assuntos
Antirreumáticos/uso terapêutico , Índices de Eritrócitos/efeitos dos fármacos , Hidroxicloroquina/uso terapêutico , Metotrexato/uso terapêutico , Antirreumáticos/administração & dosagem , Antirreumáticos/farmacologia , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Hidroxicloroquina/farmacologia , Masculino , Metotrexato/farmacologia , Pessoa de Meia-Idade , Indução de Remissão , Estudos Retrospectivos
3.
Ann Intern Med ; 174(12): 1647-1657, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34698499

RESUMO

BACKGROUND: B-cell depletion with rituximab is commonly used for patients with systemic lupus erythematosus (SLE) that is refractory to conventional therapy, but it yields variable responses. We hypothesized that high B-cell activating factor (BAFF) levels after rituximab can cause disease flares, thereby limiting its effectiveness. OBJECTIVE: To obtain preliminary evidence for efficacy of the anti-BAFF therapeutic belimumab after rituximab in SLE. DESIGN: Phase 2, randomized, double-blind (patients, assessors, researchers, care providers), placebo-controlled, parallel-group, superiority trial. (ISRCTN: 47873003). SETTING: England. PARTICIPANTS: Fifty-two patients who had SLE that was refractory to conventional treatment and whose physicians had recommended rituximab therapy were recruited between 2 February 2017 and 28 March 2019. INTERVENTION: Participants were treated with rituximab and 4 to 8 weeks later were randomly assigned (1:1) to receive intravenous belimumab or placebo for 52 weeks. MEASUREMENTS: The prespecified primary end point was serum IgG anti-double-stranded DNA (anti-dsDNA) antibody levels at 52 weeks. Secondary outcomes included incidence of disease flares and adverse events. RESULTS: At 52 weeks, IgG anti-dsDNA antibody levels were lower in patients treated with belimumab compared with placebo (geometric mean, 47 [95% CI, 25 to 88] vs. 103 [CI, 49 to 213] IU/mL; 70% greater reduction from baseline [CI, 46% to 84%]; P < 0.001). Belimumab reduced risk for severe flare (BILAG-2004 grade A) compared with placebo (hazard ratio, 0.27 [CI, 0.07 to 0.98]; log-rank P = 0.033), with 10 severe flares in the placebo group and 3 in the belimumab group. Belimumab did not increase incidence of serious adverse events. Belimumab significantly suppressed B-cell repopulation compared with placebo (geometric mean, 0.012 [CI, 0.006 to 0.014] vs. 0.037 [CI, 0.021 to 0.081] × 109/L) at 52 weeks in a subset of patients (n = 25) with available data. LIMITATIONS: Small sample size; biomarker primary end point. CONCLUSION: Belimumab after rituximab significantly reduced serum IgG anti-dsDNA antibody levels and reduced risk for severe flare in patients with SLE that was refractory to conventional therapy. The results suggest that this combination could be developed as a therapeutic strategy. PRIMARY FUNDING SOURCE: Versus Arthritis.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Rituximab/uso terapêutico , Adulto , Anticorpos Antinucleares/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino
4.
Immunity ; 32(1): 129-40, 2010 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-20079667

RESUMO

The immunosuppressive function of regulatory B cells has been shown in several murine models of chronic inflammation, including collagen-induced arthritis, inflammatory bowel disease, and experimental autoimmune encephalomyelitis. Despite interest in these cells, their relevance to the maintenance of peripheral tolerance in humans remains elusive. Here, we demonstrate that human CD19(+)CD24(hi)CD38(hi) B cells possessed regulatory capacity. After CD40 stimulation, CD19(+)CD24(hi)CD38(hi) B cells suppressed the differentiation of T helper 1 cells, partially via the provision of interleukin-10 (IL-10), but not transforming growth factor-beta (TGF-beta), and their suppressive capacity was reversed by the addition of CD80 and CD86 mAbs. In addition, CD19(+)CD24(hi)CD38(hi) SLE B cells isolated from the peripheral blood of systemic lupus erythematosus (SLE) patients were refractory to further CD40 stimulation, produced less IL-10, and lacked the suppressive capacity of their healthy counterparts. Altered cellular function within this compartment may impact effector immune responses in SLE and other autoimmune disorders.


Assuntos
Subpopulações de Linfócitos B/imunologia , Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Transdução de Sinais/imunologia , ADP-Ribosil Ciclase 1/imunologia , ADP-Ribosil Ciclase 1/metabolismo , Adulto , Idoso , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Subpopulações de Linfócitos B/metabolismo , Linfócitos B/metabolismo , Antígeno CD24/imunologia , Antígeno CD24/metabolismo , Diferenciação Celular/imunologia , Separação Celular , Citocinas/biossíntese , Citocinas/imunologia , Feminino , Citometria de Fluxo , Humanos , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Pessoa de Meia-Idade , Células Th1/imunologia , Células Th1/metabolismo , Adulto Jovem
6.
J Immunol ; 194(6): 2482-5, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25681343

RESUMO

B cells require CD4(+) T follicular helper (Tfh) cells to progress through the germinal center and provide protective Ab responses. In this article, we reveal a reciprocal interaction whereby circulating human plasmablasts are potent inducers of the Tfh cell-differentiation program, including the expression of their key transcription factor Bcl-6. The markedly increased propensity of plasmablasts, compared with naive B cells, to induce Tfh cell differentiation was due to their increased production of IL-6. Specific targeting of IL-6 using tocilizumab therapy in patients with rheumatoid arthritis led to a significant reduction in circulating Tfh cell numbers and IL-21 production, which was correlated with reduced plasmablast formation. Our data uncover a positive-feedback loop between circulating plasmablasts and Tfh cells that could sustain autoimmunity and spread Ab-driven inflammation to unaffected sites; this represents an important therapeutic target, as well as reveals a novel mechanism of action for tocilizumab.


Assuntos
Diferenciação Celular/imunologia , Interleucina-6/imunologia , Plasmócitos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Citometria de Fluxo , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Interleucina-6/metabolismo , Interleucinas/imunologia , Interleucinas/metabolismo , Plasmócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6 , Receptores CXCR5/imunologia , Receptores CXCR5/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo
7.
J Immunol ; 194(4): 1621-7, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25601923

RESUMO

Phagocytosis of apoptotic cells (ACs) is usually a potent immunoregulatory signal but can also promote inflammation. In this article, we show that administration of apoptotic dendritic cells (DCs) inhibited inflammation in vivo through increasing production of TGF-ß from intrinsic DCs and B cells. However, ACs derived from LPS-activated DCs failed to restrain inflammation because of a short-lived but marked IL-6 response, which abolished the increase in TGF-ß. Inhibition of IL-6 restored the protective anti-inflammatory properties of aACs and the TGF-ß response. DCs isolated from mice that had received resting but not activated ACs could transfer the suppression of inflammation to recipient mice. These transferred DCs stimulated B cell TGF-ß production and relied on an intact B cell compartment to limit inflammation. These results highlight how the activation state of AC governs their ability to control inflammation through reciprocal regulation of IL-6 and TGF-ß.


Assuntos
Apoptose/imunologia , Inflamação/imunologia , Interleucina-6/imunologia , Fagocitose/imunologia , Fator de Crescimento Transformador beta/imunologia , Animais , Artrite Experimental , Células Dendríticas/imunologia , Citometria de Fluxo , Interleucina-6/biossíntese , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Ann Rheum Dis ; 74(1): 294-302, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24249811

RESUMO

OBJECTIVE: To investigate whether regulatory T cells (Treg) can control B cell function in rheumatoid arthritis (RA) and if not to explore the basis for this defect. METHODS: Suppression of B cell responses by Treg was analysed in vitro by flow cytometry and ELISA using peripheral blood mononuclear cells from 65 patients with RA and 41 sex-matched and aged-matched healthy volunteers. Blocking and agonistic antibodies were used to define the role of Fas-mediated apoptosis in B cell regulation. RESULTS: Treg failed to restrain B cell activation, proinflammatory cytokine and antibody production in the presence of responder T cells in RA patients. This lack of suppression was not only caused by impaired Treg function but was also due to B cell resistance to regulation. In healthy donors, control by Treg was associated with increased B cell death and relied upon Fas-mediated apoptosis. In contrast, RA B cells had reduced Fas expression compared with their healthy counterparts and were resistant to Fas-mediated apoptosis. CONCLUSIONS: These studies demonstrate that Treg are unable to limit B cell responses in RA. This appears to be primarily due to B cell resistance to suppression, but Treg defects also contribute to this failure of regulation. Our data identify the Fas pathway as a novel target for Treg-mediated suppression of B cells and highlight a potential therapeutic approach to restore control of B cells by Treg in RA patients.


Assuntos
Apoptose/fisiologia , Artrite Reumatoide/imunologia , Linfócitos B/imunologia , Linfócitos T Reguladores/imunologia , Receptor fas/metabolismo , Linfócitos B/metabolismo , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/imunologia , Ativação Linfocitária/imunologia , Masculino
12.
Rheumatology (Oxford) ; 54(5): 768-75, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25667434

RESUMO

Regulatory T cells (Treg) are functionally defective in patients with RA. Restoring their function may not only control inflammation but also restore tolerance in these patients. Biologic therapies have been tremendously successful in treating RA. Here we review numerous reports suggesting that these immunomodulatory therapies have an impact on Treg and that this may contribute to their beneficial effects. Better understanding of their mode of action may not only lead to improvements in therapies and sustained remission but also enable the development of biomarkers of response, which would be the first steps towards personalized medicine.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Terapia Biológica , Linfócitos T Reguladores/efeitos dos fármacos , Artrite Reumatoide/patologia , Artrite Reumatoide/fisiopatologia , Humanos , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/fisiologia , Inflamação/patologia , Inflamação/fisiopatologia , Inflamação/prevenção & controle , Linfócitos T Reguladores/patologia , Linfócitos T Reguladores/fisiologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/efeitos dos fármacos
13.
Semin Immunol ; 23(3): 195-201, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21880506

RESUMO

There is accumulating evidence for regulatory T cell defects in rheumatoid arthritis and that some biologic interventions, in particular anti-TNF, can target this population. Despite the challenges in defining regulatory T cells in patients, there are a number of approaches currently being developed to utilise their potent immunosuppressive properties. Through genetic manipulation Tregs can be generated ex vivo or in vivo that target antigens present in the inflamed joint. Here we discuss these approaches, their refinement to restore tolerance in patients with rheumatoid arthritis, and strategies to prevent their conversion towards a Th17 phenotype.


Assuntos
Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Linfócitos T Reguladores/imunologia , Animais , Humanos , Imunoterapia , Tolerância a Antígenos Próprios
14.
Arthritis Rheum ; 65(10): 2672-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23839909

RESUMO

OBJECTIVE: To determine whether serum BAFF levels correlate with relapse or remission in patients with systemic lupus erythematosus (SLE) following B cell depletion therapy (BCDT) and to assess the relationship between serum BAFF levels, B cell numbers, and immunoglobulin and autoantibody levels during active disease, both before and after BCDT. METHODS: Thirty-five patients with active SLE underwent BCDT with rituximab and were monitored for a minimum of 18 months, using clinical and serologic measures of disease activity. Serum BAFF was measured sequentially by enzyme-linked immunosorbent assay before BCDT and during disease relapse or remission after B cell repopulation. RESULTS: Serum BAFF levels prior to BCDT correlated positively with the numbers of CD19+ B cells and with the levels of IgG and IgA. Following BCDT and subsequent B cell repopulation, BAFF levels were significantly higher during relapse, as compared with disease remission, and were significantly greater than at disease flare prior to BCDT. At the time of relapse after BCDT, serum BAFF levels were inversely correlated with B cell numbers, with flare at lower B cell numbers being associated with the highest BAFF levels. The correlations between serum BAFF levels and levels of IgG and IgA were lost following BCDT, but changes in serum BAFF levels correlated positively with changes in anti-double-stranded DNA (anti-dsDNA) antibody levels during relapse or remission after BCDT. CONCLUSION: The present findings suggest a significant role of BAFF in driving disease flare after B cell repopulation following BCDT. Sequential BCDT may promote ever-increasing levels of BAFF, accompanied by rising anti-dsDNA antibody levels and disease flare even at low B cell numbers. Therefore, our data justify the judicious use of BAFF blockade in a subgroup of lupus patients after BCDT.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Fator Ativador de Células B/sangue , DNA/imunologia , Lúpus Eritematoso Sistêmico/terapia , Depleção Linfocítica/efeitos adversos , Depleção Linfocítica/métodos , Adolescente , Adulto , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais Murinos/farmacologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Lúpus Eritematoso Sistêmico/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão , Rituximab , Resultado do Tratamento , Adulto Jovem
16.
Rheumatol Adv Pract ; 8(1): rkae017, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469156

RESUMO

Objectives: Outcomes of therapy for LN are often suboptimal. Guidelines offer varied options for treatment of LN and treatment strategies may differ between clinicians and regions. We aimed to assess variations in the usual practice of UK physicians who treat LN. Methods: We conducted an online survey of simulated LN cases for UK rheumatologists and nephrologists to identify treatment preferences for class IV and class V LN. Results: Of 77 respondents, 48 (62.3%) were rheumatologists and 29 (37.7%) were nephrologists. A total of 37 (48.0%) reported having a joint clinic between nephrologists and rheumatologists, 54 (70.0%) reported having a multidisciplinary team meeting for LN and 26 (33.7%) reported having a specialized lupus nurse. Of the respondents, 58 (75%) reported arranging a renal biopsy before starting the treatment. A total of 20 (69%) of the nephrologists, but only 13 (27%) rheumatologists, reported having a formal departmental protocol for treating patients with LN (P < 0.001). The first-choice treatment of class IV LN in pre-menopausal patients was MMF [41 (53.2%)], followed by CYC [15 (19.6%)], rituximab [RTX; 12 (12.5%)] or a combination of immunosuppressive drugs [9 (11.7%)] with differences between nephrologists' and rheumatologists' choices (P = 0.026). For class V LN, MMF was the preferred initial treatment, irrespective of whether proteinuria was in the nephrotic range or not. RTX was the preferred second-line therapy for non-responders. Conclusion: There was variation in the use of protocols, specialist clinic service provision, biopsies and primary and secondary treatment choices for LN reported by nephrologists and rheumatologists in the UK.

17.
J Exp Med ; 204(10): 2249-52, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17893205

RESUMO

There has been much fanfare, and rightly so, heralding a revolution in the treatment of autoimmune disease using biologic agents-antibodies or other molecules that specifically target known mediators of disease. But not all patients respond to even the most successful biologic agent, which may provide clues about alternate disease mechanisms. Studies aimed at understanding the mechanism of action of biologic agents will yield significant benefits for experimental medicine.


Assuntos
Imunoterapia , Preparações Farmacêuticas , Animais , Doença , Humanos
18.
J Exp Med ; 204(1): 33-9, 2007 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-17200409

RESUMO

The induction of regulatory T (T reg) cells holds considerable potential as a treatment for autoimmune diseases. We have previously shown that CD4+CD25hi T reg cells isolated from patients with active rheumatoid arthritis (RA) have a defect in their ability to suppress proinflammatory cytokine production by CD4+CD25- [corrected] T cells. This defect, however, was overcome after anti-tumor necrosis factor (TNF)-alpha antibody (infliximab) therapy. Here, we demonstrate that infliximab therapy gives rise to a CD4+CD25hiFoxP3+ T reg cell population, which mediates suppression via transforming growth factor (TGF)-beta and interleukin 10, and lacks CD62L expression, thereby distinguishing this T reg cell subset from natural T reg cells present in healthy individuals and patients with active RA. In vitro, infliximab induced the differentiation of CD62L- T reg cells from CD4+CD25- T cells isolated from active RA patients, a process dependent on TGF-beta. In spite of the potent suppressor capacity displayed by this CD62L- T reg cell population, the natural CD62L+ T reg cells remained defective in infliximab-treated patients. These results suggest that anti-TNF-alpha therapy in RA patients generates a newly differentiated population of T reg cells, which compensates for the defective natural T reg cells. Therefore, manipulation of a proinflammatory environment could represent a therapeutic strategy for the induction of T reg cells and the restoration of tolerance.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Artrite Reumatoide/imunologia , Artrite Reumatoide/terapia , Linfócitos T Reguladores/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Estudos de Casos e Controles , Fatores de Transcrição Forkhead/metabolismo , Humanos , Técnicas In Vitro , Infliximab , Interleucina-10/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Selectina L/metabolismo , Tolerância a Antígenos Próprios , Subpopulações de Linfócitos T/imunologia , Fator de Crescimento Transformador beta/metabolismo
19.
Arthritis Rheum ; 64(10): 3129-38, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22674488

RESUMO

OBJECTIVE: The importance of interleukin-17 (IL-17) is underscored both by its resistance to control by Treg cells and the propensity of Treg cells to produce this highly inflammatory cytokine. This study sought to address whether Th17 cells are inhibited by Treg cells in rheumatoid arthritis (RA) patients responding to anti-tumor necrosis factor (anti-TNF) therapy, and if so defining the underlying mechanisms of suppression. METHODS: Inhibition of Th17 cell responses was determined by Treg cell suppression assays. The Treg cell phenotype was analyzed using flow cytometry and enzyme-linked immunosorbent assay. Mechanisms of suppression were tested by cytokine addition or antibody blockade. RESULTS: Th17 responses were inhibited by Treg cells from RA patients responding to the anti-TNF antibody adalimumab (Treg(ada) ), but not by Treg cells from healthy individuals or patients with active RA. Furthermore, Treg(ada) cells secreted less IL-17, even when exposed to proinflammatory monocytes from patients with active RA. Treg(ada) cells suppressed Th17 cells through the inhibition of monocyte-derived IL-6, but this effect was independent of IL-10 and transforming growth factor ß, which mediated the suppression of Th1 responses. Adalimumab therapy led to a reduction in retinoic acid receptor-related orphan nuclear receptor C-positive Th17 cells and an increase in FoxP3+ Treg cells lacking expression of the transcription factor Helios. However, this acquisition of IL-17-suppressor function was not observed in RA patients responding to treatment with etanercept, a modified TNF receptor-Fc fusion protein. Indeed, there was no alteration in Treg cell number, function, or phenotype in etanercept-treated patients, and Th17 responses remained unchecked. CONCLUSION: Th1 and Th17 responses are controlled through distinct mechanisms by Treg cells from patients responding to anti-TNF antibody therapy. Adalimumab therapy, but not etanercept therapy, induces a potent and stable Treg cell population with the potential to restrain the progression of IL-17-associated inflammation in RA via regulation of monocyte-derived IL-6.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Interleucina-6/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Adalimumab , Adulto , Anticorpos Monoclonais Humanizados/farmacologia , Antirreumáticos/farmacologia , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Humanos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
20.
J Immunol ; 186(8): 4967-72, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21383247

RESUMO

The clearance of dying cells is vital for re-establishing tolerance during inflammation and has potent immunoregulatory consequences. Because natural IgM plays a key role in the removal of apoptotic cells, we investigated whether the immune modulatory properties of apoptotic cells depended on its presence. Using an Ab-independent, Ag-induced model of inflammatory arthritis, we tested whether natural IgM is essential for the arthritis-suppressing properties of apoptotic cells. Whereas administration of apoptotic cells reduced joint inflammation and damage in normal mice accompanied by suppression of the Th17 response, no protection was afforded in secreted IgM-deficient (Sµ(-)) mice. The enhanced production of IL-10 by T cells from draining lymph nodes and splenic marginal zone B cells, driven by the infusion of apoptotic cells, was abrogated in the absence of natural IgM. Apoptotic cells were present shortly after administration in the splenic marginal zone, but their removal was substantially delayed in the absence of natural IgM. Incubation of apoptotic cells with natural IgM in vitro restored their arthritis-suppressing properties in Sµ(-) mice. Moreover, these IgM-coated apoptotic cells were cleared rapidly after injection from the spleens of Sµ(-) mice. Our results demonstrate that natural IgM is a critical factor in a chain of events triggered by the administration of apoptotic cells that promote IL-10-secreting B and T cells and restrain the development of inflammation.


Assuntos
Apoptose/imunologia , Artrite Experimental/imunologia , Imunoglobulina M/imunologia , Linfócitos/imunologia , Animais , Artrite Experimental/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Feminino , Citometria de Fluxo , Imunoglobulina M/genética , Imunoglobulina M/metabolismo , Imuno-Histoquímica , Inflamação/genética , Inflamação/imunologia , Interleucina-10/imunologia , Interleucina-10/metabolismo , Articulação do Joelho/imunologia , Articulação do Joelho/metabolismo , Articulação do Joelho/patologia , Linfonodos/imunologia , Linfonodos/metabolismo , Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Baço/imunologia , Baço/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/imunologia , Células Th17/metabolismo
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