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1.
Life Sci ; 241: 117172, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31843529

RESUMO

AIMS: Allergic airway inflammation is one of the major pathological events involved in asthma, and dysregulation of regulatory T cells (Treg) plays a crucial role in the development of allergic airway inflammation. Here, we attempted to investigate the regulatory effects of B cell-activating factor (BAFF) on Tregs in allergic airway inflammation. MAIN METHODS: BAFF expression was analyzed by ELISA, quantitative reverse transcription PCR (RT-PCR) and Western blot assays. The levels of IL-4, TGF-ß, IL-2, and IL-10 were tested using ELISA kits. Flow cytometry was conducted to analyze the populations of CTLA4+ Foxp3+ Tregs. KEY FINDINGS: BAFF was found to be aberrantly expressed in sputum and lungs in patients with asthma as well as OVA sensitized mice. BAFF silencing by lentiviral BAFF shRNA reduced the number of eosinophils and levels of IL-4 in the BAL fluid, as well as the Fizz1 expression in the lungs of OVA mice. Additionally, the population of CTLA4+ Foxp3+ Tregs were significantly decreased in OVA mice and had a negative correlation to BAFF levels in asthmatic patients and OVA mice. BAFF silencing in vivo increased levels of CTLA4+ Foxp3+ Tregs and the secretion of IL-10, and improved the regulatory phenotype and suppressor function of Tregs in vitro. Furthermore, BAFF can affect Tregs generation by regulating the production of the pro-Treg cytokines IL-2 and TGF-ß. SIGNIFICANCE: BAFF has an inhibitory effect on the generation and suppressor function of Tregs by affecting pro-Tregs cytokines, thereby contributing to the development of allergic airway inflammation.


Assuntos
Asma/prevenção & controle , Fator Ativador de Células B/antagonistas & inibidores , Citocinas/metabolismo , Regulação da Expressão Gênica , Inativação Gênica , Inflamação/prevenção & controle , Linfócitos T Reguladores/imunologia , Adulto , Animais , Asma/etiologia , Asma/imunologia , Asma/patologia , Fator Ativador de Células B/genética , Estudos de Casos e Controles , Feminino , Humanos , Inflamação/etiologia , Inflamação/imunologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Ovalbumina/toxicidade
2.
MAbs ; 11(6): 1175-1190, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31181988

RESUMO

We describe a bispecific dual-antagonist antibody against human B cell activating factor (BAFF) and interleukin 17A (IL-17). An anti-IL-17 single-chain variable fragment (scFv) derived from ixekizumab (Taltz®) was fused via a glycine-rich linker to anti-BAFF tabalumab. The IgG-scFv bound both BAFF and IL-17 simultaneously with identical stoichiometry as the parental mAbs. Stability studies of the initial IgG-scFv revealed chemical degradation and aggregation not observed in either parental antibody. The anti-IL-17 scFv showed a high melting temperature (Tm) by differential scanning calorimetry (73.1°C), but also concentration-dependent, initially reversible, protein self-association. To engineer scFv stability, three parallel approaches were taken: labile complementary-determining region (CDR) residues were replaced by stable, affinity-neutral amino acids, CDR charge distribution was balanced, and a H44-L100 interface disulfide bond was introduced. The Tm of the disulfide-stabilized scFv was largely unperturbed, yet it remained monodispersed at high protein concentration. Fluorescent dye binding titrations indicated reduced solvent exposure of hydrophobic residues and decreased proteolytic susceptibility was observed, both indicative of enhanced conformational stability. Superimposition of the H44-L100 scFv (PDB id: 6NOU) and ixekizumab antigen-binding fragment (PDB id: 6NOV) crystal structures revealed nearly identical orientation of the frameworks and CDR loops. The stabilized bispecific molecule LY3090106 (tibulizumab) potently antagonized both BAFF and IL-17 in cell-based and in vivo mouse models. In cynomolgus monkey, it suppressed B cell development and survival and remained functionally intact in circulation, with a prolonged half-life. In summary, we engineered a potent bispecific antibody targeting two key cytokines involved in human autoimmunity amenable to clinical development.


Assuntos
Anticorpos Biespecíficos , Doenças Autoimunes/tratamento farmacológico , Fator Ativador de Células B/antagonistas & inibidores , Interleucina-17/antagonistas & inibidores , Anticorpos de Cadeia Única , Animais , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/farmacologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Fator Ativador de Células B/imunologia , Feminino , Células HEK293 , Células HT29 , Humanos , Interleucina-17/imunologia , Macaca fascicularis , Camundongos , Camundongos Transgênicos , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/farmacologia
3.
PLoS One ; 14(2): e0211865, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735519

RESUMO

Alloantibody represents a significant barrier in kidney transplant through the sensitization of patients prior to transplant through antibody mediated rejection (ABMR). APRIL BLyS are critical survival factors for mature B lymphocytes plasma cells, the primary source of alloantibody. We examined the effect of APRIL/BLyS blockade via TACI-Ig (Transmembrane activator calcium modulator cyclophilin lig interactor-Immunoglobulin) in a preclinical rodent model as treatment for both desensitization ABMR. Lewis rats were sensitized with Brown Norway (BN) blood for 21 days. Following sensitization, animals were then sacrificed or romized into kidney transplant (G4, sensitized transplant control); desensitization with TACI-Ig followed by kidney transplant (G5, sensitized + pre-transplant TACI-Ig); kidney transplant with post-transplant TACI-Ig for 21 days (G6, sensitized + post-transplant TACI-Ig); desensitization with TACI-Ig followed by kidney transplant post-transplant TACI-Ig for 21 days (G7, sensitized + pre- post-transplant TACI-Ig). Animals were sacrificed on day 21 post-transplant tissues were analyzed using flow cytometry, IHC, ELISPOT, RT-PCR. Sensitized animals treated with APRIL/BLyS blockade demonstrated a significant decrease in marginal zone non-switched B lymphocyte populations (p<0.01). Antibody secreting cells were also significantly reduced in the sensitized APRIL/BLyS blockade treated group. Post-transplant APRIL/BLyS blockade treated animals were found to have significantly less C4d deposition less ABMR as defined by Banff classification when compared to groups receiving APRIL/BLyS blockade before transplant or both before after transplant (p<0.0001). The finding of worse ABMR in groups receiving APRIL/BLyS blockade before both before after transplant may indicate that B lymphocyte depletion in this setting also resulted in regulatory lymphocyte depletion resulting in a worse rejection. Data presented here demonstrates that the targeting of APRIL BLyS can significantly deplete mature B lymphocytes, antibody secreting cells, effectively decrease ABMR when given post-transplant in a sensitized animal model.


Assuntos
Fator Ativador de Células B/imunologia , Dessensibilização Imunológica/métodos , Rejeição de Enxerto/prevenção & controle , Transplante de Rim , Proteínas Recombinantes de Fusão/farmacologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Animais , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/genética , Complemento C4b/antagonistas & inibidores , Complemento C4b/biossíntese , Citometria de Fluxo , Regulação da Expressão Gênica , Humanos , Imunização/métodos , Imunofenotipagem , Isoanticorpos/biossíntese , Masculino , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/biossíntese , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Plasmócitos/patologia , Ratos , Ratos Endogâmicos Lew , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
4.
Korean J Intern Med ; 34(3): 492-503, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30613065

RESUMO

Clinical trials and observational studies have established cyclophosphamide (CY) or rituximab plus glucocorticoid (GC) as standard remission induction therapies in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). However, because these regimens are associated with serious adverse drug reactions, the development of drugs with novel mechanisms of actions are needed. Progress in basic and clinical research has identified novel candidate targeting molecules, including B-cell activating factor (BAF), C5a receptor, and interleukin-6. The combination of rituximab and BAF blockade in patients with MPA and GPA is under investigation in an effort to strike a better benefit-risk balance. Phase II clinical trials of avacopan (CCX168), an orally administered C5a receptor antagonist, have suggested a reduction in the dosage of concomitant GC or the replacement of GC in patients with MPA and GPA. The results from a currently ongoing phase III trial are awaited. Anecdotal case reports and an open-label pilot study have indicated the effectiveness of tocilizumab in patients with MPA and GPA. A randomized clinical trial comparing tocilizumab and intravenous CY in combination with GC is currently in progress. Molecular targeted therapy is expected to transform the treatment strategy for MPA and GPA to allow GC-free or at least less GC-dependent forms of therapy.


Assuntos
Granulomatose com Poliangiite/tratamento farmacológico , Poliangiite Microscópica/tratamento farmacológico , Terapia de Alvo Molecular , Fator Ativador de Células B/antagonistas & inibidores , Inativadores do Complemento/uso terapêutico , Ciclofosfamida/uso terapêutico , Granulomatose com Poliangiite/complicações , Humanos , Fatores Imunológicos/uso terapêutico , Interleucina-6/antagonistas & inibidores , Poliangiite Microscópica/complicações , Rituximab/uso terapêutico
5.
EBioMedicine ; 40: 517-527, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30593436

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease, which exhibits multiple B cell abnormalities including expanded populations of memory B cells and elevated levels of autoantibodies. Belimumab is a monoclonal antibody targeting the B cell cytokine BAFF (a.k.a. BLyS), approved for the treatment of SLE. METHODS: In this prospective cohort study, B cells from peripheral blood of 23 SLE patients initiating belimumab treatment and followed longitudinally for up to three years, were assessed using mass cytometry. FINDINGS: B cells decreased during the study period, with a rapid decrease of both naïve and CD11c+CD21- B cells at the first follow-up visit, followed by a continuous reduction at subsequent follow-ups. In contrast, plasma cells and switched memory B cells remained stable throughout the study. The observed immunological changes correlated with early, but not late, clinical improvements. Moreover, high baseline B cell counts were predictive of failure to attain low disease activity. In summary, our data unveiled both rapid and gradual later therapy-associated alterations of both known and unforeseen B cell phenotypes. INTERPRETATION: Our results suggest that evaluation of B cell counts might prove useful prior to initiation of belimumab treatment and that early treatment evaluation and discontinuation might underestimate delayed clinical improvements resultant of late B cell changes.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Adulto , Anticorpos Monoclonais Humanizados/farmacologia , Subpopulações de Linfócitos B/efeitos dos fármacos , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Biomarcadores , Feminino , Humanos , Imunossupressores/farmacologia , Lúpus Eritematoso Sistêmico/diagnóstico , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
6.
Front Immunol ; 9: 2698, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30524439

RESUMO

B cell activating factor of the TNF family (BAFF, also known as BLyS), a cytokine that regulates homeostasis of peripheral B cells, is elevated in the circulation of patients with autoimmune diseases such as systemic lupus erythematosus (SLE). BAFF is synthetized as a membrane-bound protein that can be processed to a soluble form after cleavage at a furin consensus sequence, a site that in principle can be recognized by any of the several proteases of the pro-protein convertase family. Belimumab is a human antibody approved for the treatment of SLE, often cited as specific for the soluble form of BAFF. Here we show in different experimental systems, including in a monocytic cell line (U937) that naturally expresses BAFF, that belimumab binds to membrane-bound BAFF with similar EC50 as the positive control atacicept, which is a decoy receptor for both BAFF and the related cytokine APRIL (a proliferation inducing ligand). In U937 cells, binding of both reagents was only detectable in furin-deficient U937 cells, showing that furin is the main BAFF processing protease in these cells. In CHO cells expressing membrane-bound BAFF lacking the stalk region, belimumab inhibited the activity of membrane-bound BAFF less efficiently than atacicept, while in furin-deficient U937 cells, belimumab inhibited membrane-bound BAFF and residual soluble BAFF as efficiently as atacicept. These reagents did not activate complement or antibody-dependent cell cytotoxicity upon binding to membrane-bound BAFF in vitro. In conclusion, our data show that belimumab can inhibit membrane-bound BAFF, and that BAFF in U937 cells is processed by furin.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Fator Ativador de Células B/antagonistas & inibidores , Membrana Celular/imunologia , Fator Ativador de Células B/imunologia , Furina/imunologia , Células HEK293 , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Células U937
7.
J Autoimmun ; 95: 179-190, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30385081

RESUMO

Autoimmunity occurs when an adaptive immune response is directed against a self-antigen. As such, autoimmune reactions associated with the production of autoantibodies are common. These autoantibodies may either be pathogenic by inducing the initial damage to self, or exacerbate the reaction secondarily to the initial damage. In both cases, the pathway(s) leading to exposure of the immune system to the self-antigen inducing the production of autoantibodies is largely unknown. The latter is largely complicating the setting of putative prophylactic treatments. As a consequence, one possible way to control these diseases is to eliminate the cells producing antibodies. We will see that this approach is not yet part of any treatment in autoimmunity. Indeed, all the currently available non-specific immunosuppressive treatments do not target directly quiescent antibody-producing plasma cells. However, treatments aimed at depleting precursors of plasma cells, mature B-lymphocytes and/or antigen-experienced B cells not yet fully differentiated into plasma cells, are emerging. Such strategies were recently proven to be highly successful in several autoimmune disorders by two independent ways. The first way is by induction of B-cell cytotoxicity with an antibody directed against the surface antigen CD20. The second way is by antagonism of a key B-cell survival factor, the B-cell activation factor from the TNF superfamily (BAFF). In the present review, we will focus on the current knowledge regarding the role of a molecule related to BAFF, a proliferation-inducing ligand (APRIL), in autoimmune diseases, which acts on antibody-producing plasma cells. We will discuss expectations deriving from APRIL targeting in autoimmune diseases.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doenças Autoimunes/terapia , Autoimunidade/efeitos dos fármacos , Fator Ativador de Células B/imunologia , Terapia de Alvo Molecular/métodos , Plasmócitos/efeitos dos fármacos , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Antígenos CD20/genética , Antígenos CD20/imunologia , Autoanticorpos , Autoantígenos/genética , Autoantígenos/imunologia , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/genética , Subpopulações de Linfócitos B/efeitos dos fármacos , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/patologia , Citotoxicidade Imunológica , Regulação da Expressão Gênica , Humanos , Imunidade Humoral/efeitos dos fármacos , Imunossupressores/uso terapêutico , Plasmócitos/imunologia , Plasmócitos/patologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
8.
J Autoimmun ; 94: 16-32, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30219390

RESUMO

Nowadays, pharmacologic treatments of autoinflammatory diseases are largely palliative rather than curative. Most of them result in non-specific immunosuppression, which can be associated with broad disruption of natural and induced immunity with significant and sometimes serious unwanted injuries. Among the novel strategies that are under development, tools that modulate the immune system to restore normal tolerance mechanisms are central. In these approaches, peptide therapeutics constitute a class of agents that display many physicochemical advantages. Within this class of potent drugs, the phosphopeptide P140 is very promising for treating patients with lupus, and likely also patients with other chronic inflammatory diseases. We discovered that P140 targets autophagy, a finely orchestrated catabolic process, involved in the regulation of inflammation and in the biology of immune cells. In vitro, P140 acts directly on a particular form of autophagy called chaperone-mediated autophagy, which seems to be hyperactivated in certain subsets of lymphocytes in lupus and in other autoinflammatory settings. In lupus, the "correcting" effect of P140 on autophagy results in a weaker signaling of autoreactive T cells, leading to a significant improvement of pathophysiological status of treated mice. These findings also demonstrated ex vivo in human cells, open novel avenues of therapeutic intervention in pathological conditions, in which specific and not general targeting is highly pursued in the context of the new action plans for personalized medicines.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Autofagia/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Lúpus Eritematoso Sistêmico/terapia , Terapia de Alvo Molecular/métodos , Fragmentos de Peptídeos/uso terapêutico , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Autofagia/genética , Autofagia/imunologia , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Tolerância Imunológica/efeitos dos fármacos , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/patologia , Camundongos , Medicina de Precisão
9.
Lupus ; 27(12): 1926-1935, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30180771

RESUMO

Belimumab, a specific inhibitor of the soluble B lymphocyte stimulator (BlyS), is the first biological drug approved by the United States Food and Drug Administration for the treatment of patients with active systemic lupus erythematosus (SLE) refractory to standard therapy. Given that an imbalance between regulatory T cells (Treg) and interleukin (IL)-17A-secreting T cells (Th17) has been reported in various autoimmune disorders, we assessed the frequency of both Treg and Th17 peripheral blood populations before and after belimumab administration in 20 patients with active SLE refractory to standard therapy. After six months of treatment, the mean SELENA-SLEDAI score as well as the mean anti-double-stranded DNA antibody titers were significantly decreased. In addition, we observed a significant increase in Treg percentages and a parallel, significant decrease in Th17 percentages, accompanied by significantly reduced serum levels of IL-21. In vitro studies showed that Treg purified from belimumab-treated patients were fully functional and displayed a suppressor function similar to that of Treg purified from healthy donors. Belimumab can restore Treg/Th17 balance in SLE patients with uncontrolled disease activity, and this results in decreased flare rate and reduced glucocorticoid dosage.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Adulto , Anticorpos Antinucleares/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Resultado do Tratamento
10.
Nat Rev Rheumatol ; 14(10): 580-591, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30108367

RESUMO

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is an organ-threatening and life-threatening multi-system autoimmune disease in which B cell-derived ANCAs cause neutrophil activation and endothelial damage, strongly implicating these autoantibodies in the pathogenesis of AAV. B cell depletion with rituximab combined with glucocorticoids is associated with a reduction in ANCA concentrations and with clinical remission in the majority of patients with AAV. However, the safety profile of rituximab is no better than that of conventional therapy with cyclophosphamide, and long-term glucocorticoid treatment is needed to achieve and maintain disease-free remission. A need for new therapies exists to reduce the time to remission, to spare the use of glucocorticoids and to promote long-lasting remission without the risk of relapse. Over the past 20 years, there has been great interest in therapeutically targeting B cell cytokines, such as B cell-activating factor (BAFF), in many autoimmune disease settings. Dual B cell-targeted immunotherapy that combines B cell depletion and BAFF blockade could potentially be more efficacious than targeting either mechanism alone. In this Review, the theoretical background for use of this combination approach in AAV is presented and discussed.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Linfócitos B/efeitos dos fármacos , Imunoterapia/métodos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Linfócitos B/imunologia , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Terapia de Alvo Molecular , Rituximab/farmacologia , Rituximab/uso terapêutico , Resultado do Tratamento
11.
Sci Adv ; 4(7): eaas9944, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30009261

RESUMO

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and lung fibrosis. More than 90% of patients with SSc are positive for autoantibodies. In addition, serum B cell activating factor (BAFF) level is correlated with SSc severity and activity. Thus, B cells are considered to play a pathogenic role in SSc. However, there are two opposing subsets: regulatory B cells (Bregs) and effector B cells (Beffs). Interleukin-10 (IL-10)-producing Bregs negatively regulate the immune response, while IL-6-producing Beffs positively regulate it. Therefore, a protocol that selectively depletes Beffs would represent a potent therapy for SSc. The aims of this study were to investigate the roles of Bregs and Beffs in SSc and to provide a scientific basis for developing a new treatment strategy targeting B cells. A bleomycin-induced scleroderma model was induced in mice with a B cell-specific deficiency in IL-6 or IL-10. We also examined whether BAFF regulates cytokine-producing B cells and its effects on the scleroderma model. IL-6-producing Beffs increased in number and infiltrated the inflamed skin in the scleroderma model. The skin and lung fibrosis was attenuated in B cell-specific IL-6-deficient mice, whereas B cell-specific IL-10-deficient mice showed more severe fibrosis. In addition, BAFF increased Beffs but suppressed Bregs. Furthermore, BAFF antagonist attenuated skin and lung fibrosis in the scleroderma model with reduction of Beffs but not of Bregs. The current study indicates that Beffs play a pathogenic role in the scleroderma model, while Bregs play a protective role. BAFF inhibition is a potential therapeutic strategy for SSc via alteration of B cell balance.


Assuntos
Fator Ativador de Células B/metabolismo , Subpopulações de Linfócitos B/imunologia , Linfócitos B Reguladores/imunologia , Animais , Fator Ativador de Células B/antagonistas & inibidores , Subpopulações de Linfócitos B/citologia , Subpopulações de Linfócitos B/efeitos dos fármacos , Subpopulações de Linfócitos B/metabolismo , Linfócitos B Reguladores/citologia , Linfócitos B Reguladores/efeitos dos fármacos , Linfócitos B Reguladores/metabolismo , Bleomicina/toxicidade , Colágeno/metabolismo , Modelos Animais de Doenças , Feminino , Fibrose , Interleucina-10/sangue , Interleucina-10/deficiência , Interleucina-10/genética , Interleucina-6/sangue , Interleucina-6/deficiência , Interleucina-6/genética , Lipopolissacarídeos/farmacologia , Pneumopatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Escleroderma Sistêmico/induzido quimicamente , Escleroderma Sistêmico/metabolismo , Escleroderma Sistêmico/patologia , Dermatopatias/patologia
12.
Nat Commun ; 9(1): 1200, 2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29572471

RESUMO

BAFF, a member of the TNF superfamily, has been recognized as a good target for autoimmune diseases. Belimumab, an anti-BAFF monoclonal antibody, was approved by the FDA for use in treating systemic lupus erythematosus. However, the molecular basis of BAFF neutralization by belimumab remains unclear. Here our crystal structure of the BAFF-belimumab Fab complex shows the precise epitope and the BAFF-neutralizing mechanism of belimumab, and demonstrates that the therapeutic activity of belimumab involves not only antagonizing the BAFF-receptor interaction, but also disrupting the formation of the more active BAFF 60-mer to favor the induction of the less active BAFF trimer through interaction with the flap region of BAFF. In addition, the belimumab HCDR3 loop mimics the DxL(V/L) motif of BAFF receptors, thereby binding to BAFF in a similar manner as endogenous BAFF receptors. Our data thus provides insights for the design of new drugs targeting BAFF for the treatment of autoimmune diseases.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Fator Ativador de Células B/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Motivos de Aminoácidos , Fator Ativador de Células B/metabolismo , Receptor do Fator Ativador de Células B/antagonistas & inibidores , Receptor do Fator Ativador de Células B/metabolismo , Linfócitos B/imunologia , Cromatografia em Gel , Cristalografia por Raios X , Epitopos/química , Humanos , Imunossupressores/farmacologia , Ligantes , Mutação , Ligação Proteica
13.
Ann Rheum Dis ; 77(6): 883-889, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29563108

RESUMO

BACKGROUND: Targeted inhibitors of B-cell activating factor (BAFF) have been evaluated in phase III trials in over 4000 patients with systemic lupus erythematosus (SLE). Post hoc analyses of these studies identify greater treatment effect in patients entering with higher disease activity, greater corticosteroid doses, anti double-stranded DNA (dsDNA) and low complement C3 or C4. OBJECTIVES: To evaluate the efficacy and safety of blisibimod, a BAFF inhibitor, in a population of patients with SLE enriched for high disease activity. METHODS: 442 patients with SLE with antinuclear antibodies or anti-dsDNA and Safety of Estrogen in Lupus Erythematosus National Assessment - Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score ≥10 on standard-of-care medications were randomised to receive weekly subcutaneous blisibimod (200 mg) or placebo. Corticosteroid taper was encouraged from week 8. The primary end point was the week 52 SLE Responder Index-6 (SRI-6). RESULTS: The SRI-6 primary end point was not met. There was a statistically significant steroid-sparing effect, and significantly more blisibimod-treated subjects achieved corticosteroid taper. Increased blisibimod treatment effect on SRI-6 was observed in subjects who achieved a concomitant decrease in corticosteroid dose from baseline. In subjects with baseline urinary protein:creatinine ratio (UPCR) ≥56.5 mg/mmol, significantly higher proportions of blisibimod subjects achieved >50% reduction in UPCR and/or UPCR <56.5 mg/mmol. Reductions in SLE autoantibodies and B cells, and increases in complement C3 and C4 were observed with blisibimod.Blisibimod was well-tolerated. The most common adverse events were upper respiratory tract infection, urinary tract infection, injection site erythema/reaction and diarrhoea. CONCLUSIONS: Although the SRI-6 end point was not met, blisibimod was associated with successful steroid reduction, decreased proteinuria and biomarker responses. TRIAL REGISTRATION NUMBER: NCT01395745.


Assuntos
Fator Ativador de Células B/antagonistas & inibidores , Fatores Imunológicos/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Proteínas Recombinantes de Fusão/uso terapêutico , Adulto , Anticorpos Antinucleares/sangue , Linfócitos B/imunologia , Biomarcadores/sangue , Método Duplo-Cego , Esquema de Medicação , Quimioterapia Combinada , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/efeitos adversos , Injeções Subcutâneas , Lúpus Eritematoso Sistêmico/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Qualidade de Vida , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/efeitos adversos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
14.
Drugs ; 78(3): 355-366, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29396833

RESUMO

Belimumab (Benlysta®) is a human immunoglobulin G1λ monoclonal antibody that inhibits the binding of soluble B lymphocyte stimulator to B cells. It is the only biological agent currently approved for the treatment of non-renal systemic lupus erythematosus (SLE). Belimumab is approved in the EU, the USA and other countries as add-on therapy in adult patients with active, autoantibody-positive SLE despite standard therapy. In phase III trials, treatment with IV or SC belimumab plus standard therapy was effective in terms of reducing overall disease activity and reducing the incidence and severity of flares, without worsening of patients' overall condition or the development of significant disease activity in new organ systems. Sustained disease control was maintained during longer-term (up to 10 years) treatment with IV belimumab. Belimumab also demonstrated steroid-sparing effects and was associated with clinically meaningful improvements in health-related quality of life and fatigue. Belimumab was generally well tolerated in clinical trials, with low rates of immunogenicity. In view of the flexibility regarding the route of administration and the convenience of the once-weekly, self-administered, SC regimen, add-on therapy with belimumab is a useful treatment option for patients with active, autoantibody-positive SLE despite standard therapy.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/metabolismo , Linfócitos B/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imunoglobulina G/imunologia , Cadeias lambda de Imunoglobulina/imunologia , Ligação Proteica , Qualidade de Vida , Resultado do Tratamento
15.
Arthritis Rheumatol ; 70(2): 266-276, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29073347

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of atacicept, an antagonist of B lymphocyte stimulator/APRIL-mediated B cell activation, in patients with systemic lupus erythematosus (SLE). METHODS: ADDRESS II is a 24-week, multicenter, randomized, double-blind, placebo-controlled, parallel-arm, phase IIb study evaluating the safety and efficacy of atacicept in patients with SLE (ClinicalTrials.gov identifier NCT01972568). Patients with active, autoantibody-positive SLE receiving standard therapy were randomized (1:1:1) to receive atacicept (75 mg or 150 mg) or placebo for 24 weeks. The primary end point was the SLE responder index 4 (SRI-4) at week 24. RESULTS: The intent-to-treat (ITT) population included 306 patients. There was a trend toward an improved SRI-4 response rate with atacicept 75 mg (57.8%; adjusted odds ratio [OR] 1.78, P = 0.045) and 150 mg (53.8%; adjusted OR 1.56, P = 0.121) at week 24 as compared with placebo (44.0%) (primary analysis; using the screening visit as baseline). In a prespecified sensitivity analysis using study day 1 as baseline, a significantly larger proportion of patients receiving atacicept 75 mg and 150 mg achieved an SRI-4 response at week 24 compared with placebo. In predefined subpopulations with high levels of disease activity (HDA) at baseline, serologically active disease, or both, statistically significant improvements in the SRI-4 and SRI-6 response rates were seen with atacicept versus placebo. A severe risk of disease flare was reduced with atacicept therapy in both the ITT and the HDA populations. The risks of serious adverse events and serious or severe infection were not increased with atacicept as compared with placebo. CONCLUSION: Atacicept treatment showed evidence of efficacy in SLE, particularly in HDA and serologically active patients. Reductions in disease activity and severe flare were observed with atacicept treatment, with an acceptable safety profile.


Assuntos
Fator Ativador de Células B/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Proteínas Recombinantes de Fusão/uso terapêutico , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/antagonistas & inibidores , Adulto , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Glucocorticoides/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/efeitos adversos , Índice de Gravidade de Doença , Resultado do Tratamento
16.
Rheumatology (Oxford) ; 57(1): 125-133, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29045736

RESUMO

Objective: The SLE Responder Index (SRI) is a composite endpoint used in SLE trials. This investigation examined the clinical trial elements that drive response measured by the SRI. Methods: Analyses are based on data from two phase 3 trials (n = 2262) that evaluated the impact of an anti-B-cell activating factor antibody on disease activity using SRI-5 as the primary endpoint (ClinicalTrials.gov NCT01196091 and NCT01205438). Results: The SRI-5 response rate at week 52 for all patients was 32.8%. Non-response due to a lack of SLEDAI improvement, concomitant medication non-compliance or dropout was 31, 16.5 and 19.1%, respectively. Non-response due to deterioration in BILAG or Physician's Global Assessment after SLEDAI improvement, concomitant medication compliance and trial completion was 0.5%. Disease activity in three SLEDAI organ systems was highly prevalent at baseline: mucocutaneous, 90.6%; musculoskeletal, 82.9%; and immunologic, 71.6%. Disease activity in each of the other organ systems was <11% of patients. Four clinical manifestations were highly prevalent at baseline: arthritis, 82.6%; rash, 69.2%; alopecia, 58.2%; and mucosal ulcer, 32.5%. The combined prevalence of renal, vascular and CNS disease at baseline was 17.6%; these patients had high SRI-5 response rates. Adjustments to corticosteroids were allowed during the first 24 weeks. Increases in corticosteroids above 2.5 mg/day were observed in 16.2% of placebo patients over the first 24 weeks after randomization. Conclusion: The primary drivers of SRI-5 response were SLEDAI improvement, concomitant medication adherence and trial completion. Arthritis, rash, alopecia and mucosal ulcer were the most prevalent clinical manifestations at baseline. Corticosteroid increases and rare, highly weighted disease manifestations in SLEDAI can confound the SRI signal.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Corticosteroides/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Ensaios Clínicos como Assunto , Ensaios Clínicos Fase III como Assunto , Quimioterapia Combinada , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Adesão à Medicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
17.
Cell Death Dis ; 8(11): e3161, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29095438

RESUMO

We aimed to characterize the role of B-cell activating factor (BAFF) in macrophage-mediated resistance of multiple myeloma (MM) cells to bortezomib (bort), and to further understand the molecular mechanisms involved in the process. First, we detected BAFF and its three receptors on myeloma cells and macrophages using the quantitative reverse transcriptase-polymerase chain reaction and flow cytometry. The secretion of BAFF was tested in patients with MM, MM cell lines, and macrophages. The ability of macrophages to protect MM cells from bort-induced apoptosis was significantly attenuated using BAFF-neutralizing antibody in the co-culture system or knocking down the expression of BAFF in macrophages with small interfering RNA. We also showed that the MM-macrophage interaction through BAFF and its receptors was primarily mediated by the activation of Src, Erk1/2, Akt, and nuclear factor kappa B signaling and the suppression of caspase activation induced by bort. Our data demonstrated that BAFF played a functional role in the macrophage-mediated resistance of MM cells to bort, suggesting that targeting BAFF may provide a basis for the molecular- and immune-targeted therapeutic approach.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fator Ativador de Células B/metabolismo , Bortezomib/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Antineoplásicos/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Bortezomib/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
J Immunol ; 199(11): 3757-3770, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29055002

RESUMO

In NOD mice and also likely humans, B lymphocytes play an important role as APC-expanding autoreactive T cell responses ultimately causing type 1 diabetes (T1D). Currently, humans at high future T1D risk can only be identified at late prodromal stages of disease indicated by markers such as insulin autoantibodies. When commenced in already insulin autoantibody+ NOD mice, continuous BAFFR-Fc treatment alone or in combination with anti-CD20 (designated combo therapy) inhibited T1D development. Despite eliciting broader B lymphocyte depletion, continuous combo therapy afforded no greater T1D protection than did BAFFR-Fc alone. As previously observed, late disease stage-initiated anti-CD20 monotherapy did not inhibit T1D, and in this study was additionally found to be associated with development of drug-blocking Abs. Promisingly, NOD mice given transient late disease stage BAFFR-Fc monotherapy were rendered T1D resistant. However, combo treatment abrogated the protective effect of transient BAFFR-Fc monotherapy. NOD mice receiving transient BAFF blockade were characterized by an enrichment of regulatory B lymphocytes that inhibit T1D development through IL-10 production, but this population is sensitive to deletion by anti-CD20 treatment. B lymphocytes from transient BAFFR-Fc-treated mice suppressed T cell proliferation to a greater extent than did those from controls. Proportions of B lymphocytes expressing CD73, an ecto-enzyme operating in a pathway converting proinflammatory ATP to anti-inflammatory adenosine, were also temporarily increased by transient BAFFR-Fc treatment, but not anti-CD20 therapy. These collective studies indicate transient BAFFR-Fc-mediated B lymphocyte depletion elicits long-term T1D protection by enriching regulatory B lymphocytes that are deleted by anti-CD20 cotherapy.


Assuntos
Fator Ativador de Células B/antagonistas & inibidores , Linfócitos B Reguladores/imunologia , Diabetes Mellitus Tipo 1/imunologia , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Imunoterapia/métodos , Rituximab/uso terapêutico , Linfócitos T/imunologia , Animais , Receptor do Fator Ativador de Células B/genética , Receptor do Fator Ativador de Células B/uso terapêutico , Proliferação de Células , Células Cultivadas , Terapia Combinada , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Imunossupressão , Interleucina-10/metabolismo , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD
19.
Expert Rev Clin Immunol ; 13(10): 925-938, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28847197

RESUMO

INTRODUCTION: Loss of B cell tolerance is a hallmark feature of the pathogenesis of Systemic Lupus Erythematosus (SLE). Recent advances in B cell therapy have focused on targeted therapy aimed at inhibiting B cell activation and reducing B cell survival. Belimumab, a human monoclonal antibody against B cell activating factor (BAFF) was licensed in 2011 for the treatment of SLE. Areas covered: We review the data on the intravenous and subcutaneous formulations of belimumab in the management of patients with SLE. BLISS-52 and BLISS-76 demonstrated the efficacy of intravenous belimumab (10mg/kg) as an add-on therapy in SLE patients with active disease. A recent phase III trial of intravenous belimumab reported similar results in North East Asian patients. Subcutaneous belimumab (200mg/weekly) has demonstrated similar efficacy, safety and tolerability and was approved by the FDA in 2017 for the treatment of active autoantibody positive SLE patients receiving standard therapy. Expert commentary: Belimumab is generally safe and well tolerated. The most common clinical manifestations of SLE in the clinical trials were arthritis, mucocutaneous disease and serositis. Patients with severe lupus nephritis and central nervous system disease were excluded from these clinical trials.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Imunoterapia/métodos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Administração Intravenosa , Artrite , Fator Ativador de Células B/antagonistas & inibidores , Fator Ativador de Células B/imunologia , Ensaios Clínicos como Assunto , Dermatite , Aprovação de Drogas , Prova Pericial , Humanos , Injeções Subcutâneas , Terapia de Alvo Molecular , Serosite
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