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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.
Infect Immun ; 87(10)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31383744

RESUMO

Reproductive tract pathology caused by Chlamydia trachomatis infection is an important global cause of human infertility. To better understand the mechanisms associated with Chlamydia-induced genital tract pathogenesis in humans, we used CRISPR genome editing to disrupt Toll-like receptor 3 (TLR3) function in the human oviduct epithelial (hOE) cell line OE-E6/E7 in order to investigate the possible role(s) of TLR3 signaling in the immune response to Chlamydia Disruption of TLR3 function in these cells significantly diminished the Chlamydia-induced synthesis of several inflammation biomarkers, including interferon beta (IFN-ß), interleukin-6 (IL-6), interleukin-6 receptor alpha (IL-6Rα), soluble interleukin-6 receptor beta (sIL-6Rß, or gp130), IL-8, IL-20, IL-26, IL-34, soluble tumor necrosis factor receptor 1 (sTNF-R1), tumor necrosis factor ligand superfamily member 13B (TNFSF13B), matrix metalloproteinase 1 (MMP-1), MMP-2, and MMP-3. In contrast, the Chlamydia-induced synthesis of CCL5, IL-29 (IFN-λ1), and IL-28A (IFN-λ2) was significantly increased in TLR3-deficient hOE cells compared to their wild-type counterparts. Our results indicate a role for TLR3 signaling in limiting the genital tract fibrosis, scarring, and chronic inflammation often associated with human chlamydial disease. Interestingly, we saw that Chlamydia infection induced the production of biomarkers associated with persistence, tumor metastasis, and autoimmunity, such as soluble CD163 (sCD163), chitinase-3-like protein 1, osteopontin, and pentraxin-3, in hOE cells; however, their expression levels were significantly dysregulated in TLR3-deficient hOE cells. Finally, we demonstrate using hOE cells that TLR3 deficiency resulted in an increased amount of chlamydial lipopolysaccharide (LPS) within Chlamydia inclusions, which is suggestive that TLR3 deficiency leads to enhanced chlamydial replication and possibly increased genital tract pathogenesis during human infection.


Assuntos
Chlamydia trachomatis/imunologia , Células Epiteliais/microbiologia , Regulação da Expressão Gênica/imunologia , Interações Hospedeiro-Patógeno/imunologia , Receptor 3 Toll-Like/imunologia , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Linhagem Celular Transformada , Quimiocina CCL5/genética , Quimiocina CCL5/imunologia , Chlamydia trachomatis/crescimento & desenvolvimento , Chlamydia trachomatis/patogenicidade , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/imunologia , Células Epiteliais/imunologia , Tubas Uterinas/imunologia , Tubas Uterinas/microbiologia , Feminino , Deleção de Genes , Células HeLa , Interações Hospedeiro-Patógeno/genética , Humanos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Interleucinas/genética , Interleucinas/imunologia , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/imunologia , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/imunologia , Transdução de Sinais , Receptor 3 Toll-Like/deficiência , Receptor 3 Toll-Like/genética
3.
J Immunol Res ; 2019: 8042097, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31240234

RESUMO

B cell activating factor (BAFF), a member of the tumor necrosis factor (TNF) family, plays a critical role in the pathogenesis and progression of rheumatoid arthritis (RA). Chlorogenic acid (CGA) is a phenolic compound and exerts antiarthritic activities in arthritis. However, it is not clear whether the anti-inflammatory property of CGA is associated with the regulation of BAFF expression. In this study, we found that treatment of the collagen-induced arthritis (CIA) mice with CGA significantly attenuated arthritis progression and markedly inhibited BAFF production in serum as well as the production of serum TNF-α. Furthermore, CGA inhibits TNF-α-induced BAFF expression in a dose-dependent manner and apoptosis in MH7A cells. Mechanistically, we found the DNA-binding site for the transcription factor NF-κB in the BAFF promoter region is required for this regulation. Moreover, CGA reduces the DNA-binding activity of NF-κB to the BAFF promoter region and suppresses BAFF expression through the NF-κB pathway in TNF-α-stimulated MH7A cells. These results suggest that CGA may serve as a novel therapeutic agent for the treatment of RA by targeting BAFF.


Assuntos
Fator Ativador de Células B/genética , Ácido Clorogênico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Artrite Experimental , Fator Ativador de Células B/metabolismo , Biomarcadores , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Regiões Promotoras Genéticas , Ativação Transcricional , Fator de Necrose Tumoral alfa/metabolismo
4.
Mol Immunol ; 112: 59-71, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31078117

RESUMO

B-cell survival depends on signals induced by binding of B-cell activating factor (BAFF) to its receptor (BAFF-R). In this study, the full-length cDNAs of cat BAFF (cBAFF) and BAFF-R (cBAFF-R) were amplified from the spleen by reverse transcription PCR. The open reading frame of cBAFF cDNA encodes a protein of 285 amino acids containing a predicted transmembrane domain and a furin protease cleavage site, similar to mammalian, avian, and reptile BAFFs. The cBAFF-R gene encodes a 189 amino acid protein. Real-time quantitative PCR analyses revealed that the two genes are predominantly expressed in the spleen. csBAFF, EGFP/csBAFF, and cBAFF-R were efficiently expressed in Escherichia coli BL21 (DE3), as confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analyses. After purification, the EGFP/csBAFF fusion protein showed a fluorescence spectrum similar to that of EGFP. Confocal laser scanning microscopy showed that EGFP/csBAFF bound to its receptor. In vitro, csBAFF promoted the survival of cat and mouse splenic B cells with/without a priming agent (Staphylococcus aureus Cowan 1, SAC) or anti-mouse IgM. Furthermore, it stimulated the survival of mouse B cells, similar to msBAFF. Recombinant cBAFF-R blocked the function of sBAFF in vitro. These findings indicate that csBAFF plays an important role in the survival of cat B cells and has functional cross reactivity between cats and other mammals, and suggest a role for the BAFF-BAFF-R system in regulating B-cell survival. Therefore, BAFF and BAFF-R show promise for enhancing the immune systems of animals.


Assuntos
Fator Ativador de Células B/genética , Receptor do Fator Ativador de Células B/genética , Linfócitos B/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Gatos , Sobrevivência Celular/genética , Clonagem Molecular , Reações Cruzadas/genética , DNA Complementar/genética , Escherichia coli/genética , Imunoglobulina M/genética , Mamíferos/genética , Camundongos , Estrutura Molecular , Fases de Leitura Aberta/genética , Proteínas Recombinantes/genética , Baço/metabolismo , Staphylococcus aureus/genética
5.
BMC Pregnancy Childbirth ; 19(1): 169, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088412

RESUMO

BACKGROUND: Tubal pregnancy is recognized as one of the most common ectopic pregnancy types. Salpingitis may result in tubal pregnancy by causing fallopian tube occlusion and hydrosalpinx. B cell activation factor (BAFF) is a proinflammatory cytokine that helps regulate both innate and adaptive immune responses. Our previous study firstly showed that BAFF immunostaining appeared on the cellular membrane and in the cytoplasm of tubal epithelial cells, and both BAFF protein and mRNA in human inflamed fallopian tubes had higher expression levels than those in normal fallopian tubes. This study aimed to elucidate the association between the expression of BAFF gene and the inflammation in the human fallopian tube leading to tubal pregnancy. METHODS: We examined 70 patients undergoing salpingectomy for salpingitis (n = 35) and tubal pregnancy (n = 35). Twenty patients with benign uterine diseases undergoing complete hysterectomy and salpingectomy were recruited into control group. BAFF mRNA and protein in tissue samples were detected by qPCR and Western blotting methods. Furthermore, serum levels of BAFF, tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 were measured using ELISA kits. RESULTS: We found statistically significantly elevated expressions of BAFF mRNA or protein in whole tissue samples, and serum levels of BAFF, TNF-α and IL-6 in whole blood samples from patients with salpingitis and tubal pregnancy, in comparison to the control group. CONCLUSION: Based on the results, high expression of BAFF gene might induce inflammation in the human fallopian tube, suggesting its possible role in the tubal pregnancy process.


Assuntos
Fator Ativador de Células B/genética , Fator Ativador de Células B/metabolismo , Gravidez Tubária/metabolismo , Salpingite/genética , Salpingite/metabolismo , Adulto , Fator Ativador de Células B/sangue , Estudos de Casos e Controles , Tubas Uterinas , Feminino , Expressão Gênica , Humanos , Interleucina-6/sangue , Gravidez , Gravidez Tubária/sangue , Gravidez Tubária/etiologia , RNA Mensageiro/metabolismo , Salpingite/complicações , Fator de Necrose Tumoral alfa/sangue
6.
Clin Exp Med ; 19(2): 183-190, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30747361

RESUMO

B cell-activating factor (BAFF) promotes the survival, proliferation and maturation of B lymphocytes, which are key elements in the pathogenesis of systemic lupus erythematosus (SLE). This cytokine is encoded on TNFSF13B gene, and diverse single-nucleotide polymorphisms have been associated with susceptibility in different autoimmune disorders. In this study, the relationship of TNFSF13B gene rs9514827T>C, rs1041567T>A and rs9514828C>T polymorphisms, mRNA expression and soluble BAFF levels was investigated in 175 SLE patients and 208 healthy controls (HC). The TNFSF13B polymorphisms were evaluated by PCR-RFLP technique. The TNFSF13B gene expression was quantified through the RT-PCR assays. The soluble BAFF (sBAFF) levels were measured with ELISA test. There were no differences in genotype and allele frequencies for the three TNFSF13B polymorphisms, between SLE patients and HC. SLE patients showed 3.15-fold more TNFSF13B gene expression than HC. The patients who displayed most mRNA expression were those with active disease and the carriers of rs9514828 T variant allele. The sBAFF serum levels were higher in SLE patients compared to HC (2.083 vs. 0.742 ng/mL, p < 0.001). The SLE patients with active disease showed the higher sBAFF serum levels (2.403 ng/mL), mainly patients with lupus nephritis and hematological manifestations. In addition, a correlation of sBAFF with disease activity was found (r = 0.32, p < 0.001). In conclusion, the TNFSF13B gene polymorphisms were not found to be associated with SLE susceptibility in Mexican mestizos. Nevertheless, rs9514828C>T polymorphism seems to increase TNFSF13B gene expression. High BAFF expression is related to active disease, renal and hematological involvement; therefore, it could be considered as follow-up biomarker in SLE patients.


Assuntos
Fator Ativador de Células B/biossíntese , Fator Ativador de Células B/genética , Expressão Gênica , Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Frequência do Gene , Genótipo , Humanos , México , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
7.
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
8.
Int Immunopharmacol ; 67: 473-482, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30597293

RESUMO

Activated B cells targeted to autoantigens proliferate and differentiate into antibody-secreting cells. Overproduced autoantibodies will give rise to autoimmune diseases. In this study, we investigated the inhibitory effects of GYF-21, an epoxide 2­(2­phenethyl)­chromone derivative extracted from Chinese agarwood, on the survival, activation, proliferation, and differentiation of B cells for revealing its potential to treat autoimmune diseases related to B cell dysfunction. The results showed that GYF-21 slightly inhibited the survival, activation and proliferation of B cells stimulated by combination of anti-IgM, anti-CD40 and IL-4 while weakly up-regulated differentiation of B cells induced by combination of anti-CD40 and IL-4. In addition, GYF-21 intensively suppressed survival, activation, proliferation, and differentiation of B cells stimulated by B-cell activating factor (BAFF) which plays extremely important roles in autoantibody production and pathogenesis of autoimmune diseases. The mechanism study revealed that GYF-21 slightly down-regulated phosphorylation of NF-κB p65, Akt, STAT3, but up-regulated phosphorylation of Erk1/2 in B cells activated by anti-IgM, anti-CD40, IL-4 or their combinations. However, GYF-21 not only moderately down-regulated phosphorylation of NF-κB p65 and MAPK p38, but also intensively inhibited phosphorylation of Erk1/2 and Akt induced by BAFF. These data suggest the inhibitory effects of GYF-21 on the survival, activation, proliferation, and differentiation of B cells mainly via blocking BAFF activated signaling pathways, and its potential to be developed into therapeutic drug for autoimmune diseases, especially systemic lupus erythematosus (SLE).


Assuntos
Fator Ativador de Células B/metabolismo , Linfócitos B/efeitos dos fármacos , Cromonas/farmacologia , Animais , Anticorpos , Fator Ativador de Células B/genética , Antígenos CD40/imunologia , Proliferação de Células/efeitos dos fármacos , Cromonas/química , Imunoglobulina M/imunologia , Interleucina-4/imunologia , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos
9.
Fish Shellfish Immunol ; 85: 9-17, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28989090

RESUMO

In teleost fish, IgM+ B cells are one of the main responders against inflammatory stimuli in the peritoneal cavity, as IgM+ B cells dominate the peritoneum after intraperitoneal stimulation, also increasing the levels of secreted IgM. BAFF, a cytokine known to play a major role in B cell biology, has been shown to be up-regulated along with its receptors in the peritoneum of rainbow trout upon antigenic exposure, however, the regulatory mechanisms underneath this response remain unclear. In this study, we have identified two different IgM+ B cell types residing in the peritoneal cavity of previously vaccinated rainbow trout (Oncorhynchus mykiss): IgD+IgMhiMHCIIhi cells, resembling naïve B cells, and IgD-IgMloMHCIIlo cells, resembling antibody-secreting cells. Based on their membrane IgM levels, these cell types were named IgMhi and IgMlo B cells, respectively. As each of these B cell populations showed a distinct expression pattern for the different BAFF receptors, we studied the effect of BAFF individually on each cell subset. Recombinant BAFF promoted the survival of IgMlo but not IgMhi B cells in vitro, resulting in increased levels of IgM-secreting cells. In contrast, BAFF increased the levels of membrane MHC II only on IgMhi B cells, suggesting different functions on these B cell subsets. Moreover, we also showed that peritoneal IgMhi B cells expressed BAFF at levels comparable to those seen on myeloid cells. These results point to BAFF as a main regulator of B cell homeostasis in the peritoneal cavity, suggesting that this cytokine can trigger different signals on different peritoneal B cell subsets in a specific manner.


Assuntos
Fator Ativador de Células B/genética , Linfócitos B/imunologia , Proteínas de Peixes/genética , Imunoglobulina M/metabolismo , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Animais , Fator Ativador de Células B/metabolismo , Proteínas de Peixes/metabolismo , Cavidade Peritoneal/fisiologia , Vacinação/veterinária
10.
Front Immunol ; 9: 2871, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30574145

RESUMO

Breaking tolerance is a key event leading to autoimmunity, but the exact mechanisms responsible for this remain uncertain. Here we show that the alarmin IL-33 is able to drive the generation of autoantibodies through induction of the B cell survival factor BAFF. A temporary, short-term increase in IL-33 results in a primary (IgM) response to self-antigens. This transient DNA-specific autoantibody response was dependent on the induction of BAFF. Notably, radiation resistant cells and not myeloid cells, such as neutrophils or dendritic cells were the major source of BAFF and were critical in driving the autoantibody response. Chronic exposure to IL-33 elicited dramatic increases in BAFF levels and resulted in elevated numbers of B and T follicular helper cells as well as germinal center formation. We also observed class-switching from an IgM to an IgG DNA-specific autoantibody response. Collectively, the results provide novel insights into a potential mechanism for breaking immune-tolerance via IL-33-mediated induction of BAFF.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Fator Ativador de Células B/metabolismo , Tolerância Imunológica , Interleucina-33/imunologia , Animais , Autoantígenos/administração & dosagem , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Células Dendríticas , Modelos Animais de Doenças , Humanos , Imunoglobulina M/imunologia , Interleucina-33/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos , Cultura Primária de Células , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia
11.
PLoS One ; 13(12): e0209343, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30586461

RESUMO

BACKGROUND: The TNFSF13B (TNF superfamily member 13b) gene encodes BAFF, a cytokine with a crucial role in the differentiation and activation of B cells. An insertion-deletion variant (GCTGT→A) of this gene, leading to increased levels of BAFF, has been recently implicated in the genetic predisposition to several autoimmune diseases, including multiple sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. Based on the elevated levels of this cytokine found in patients with giant cell arteritis (GCA) and systemic sclerosis (SSc), we aimed to assess whether this functional variant also represents a novel genetic risk factor for these two disorders. METHODS: A total of 1,728 biopsy-proven GCA patients from 4 European cohorts, 4,584 SSc patients from 3 European cohorts and 5,160 ethnically-matched healthy controls were included in the study. The single nucleotide polymorphism (SNP) rs374039502, which colocalizes with the genetic variant previously implicated in autoimmunity, was genotyped using a custom TaqMan assay. First, association analysis was conducted in each independent cohort using χ2 test in Plink (v1.9). Subsequently, different case/control sets were meta-analyzed by the inverse variance method. RESULTS: No statistically significant differences were found when allele distributions were compared between cases and controls for any of the analyzed cohorts. Similarly, combined analysis of the different sets evidenced a lack of association of the rs374039502 variant with GCA (P = 0.421; OR (95% CI) = 0.92 (0.75-1.13)) and SSc (P = 0.500; OR (95% CI) = 1.05 (0.91-1.22)). The stratified analysis considering the main clinical subphenotypes of these diseases yielded similar negative results. CONCLUSION: Our data suggest that the TNFSF13B functional variant does not contribute to the genetic network underlying GCA and SSc.


Assuntos
Fator Ativador de Células B/genética , Predisposição Genética para Doença , Arterite de Células Gigantes/genética , Escleroderma Sistêmico/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Estudos de Casos e Controles , Estudos de Coortes , Europa (Continente) , Feminino , Redes Reguladoras de Genes/genética , Técnicas de Genotipagem , Arterite de Células Gigantes/patologia , Humanos , Mutação INDEL , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Escleroderma Sistêmico/patologia
12.
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
13.
Nucleic Acids Res ; 46(22): 12040-12051, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30272251

RESUMO

Polymorphisms in untranslated regions (UTRs) of disease-associated mRNAs can alter protein production. We recently identified a genetic variant in the 3'UTR of the TNFSF13B gene, encoding the cytokine BAFF (B-cell-activating factor), that generates an alternative polyadenylation site yielding a shorter, more actively translated variant, BAFF-var mRNA. Accordingly, individuals bearing the TNFSF13B variant had higher circulating BAFF and elevated risk of developing autoimmune diseases. Here, we investigated the molecular mechanisms controlling the enhanced translation of BAFF-var mRNA. We identified nuclear factor 90 (NF90, also known as ILF3) as an RNA-binding protein that bound preferentially the wild-type (BAFF-WT mRNA) but not BAFF-var mRNA in human monocytic leukemia THP-1 cells. NF90 selectively suppressed BAFF translation by recruiting miR-15a to the 3'UTR of BAFF-WT mRNA. Our results uncover a paradigm whereby an autoimmunity-causing BAFF polymorphism prevents NF90-mediated recruitment of microRNAs to suppress BAFF translation, raising the levels of disease-associated BAFF.


Assuntos
Regiões 3' não Traduzidas/genética , Fator Ativador de Células B/genética , Fator Ativador de Células B/metabolismo , MicroRNAs/fisiologia , Proteínas do Fator Nuclear 90/fisiologia , Polimorfismo Genético , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Regulação para Baixo/genética , Células HeLa , Humanos , Proteínas do Fator Nuclear 90/metabolismo , Polimorfismo Genético/fisiologia , Ligação Proteica , Biossíntese de Proteínas/genética , RNA Mensageiro/metabolismo , Células THP-1
14.
J Immunol ; 201(11): 3258-3268, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30373855

RESUMO

The B cell survival cytokine BAFF has been linked with the pathogenesis of systemic lupus erythematosus (SLE). BAFF binds distinct BAFF-family surface receptors, including the BAFF-R and transmembrane activator and CAML interactor (TACI). Although originally characterized as a negative regulator of B cell activation, TACI signals are critical for class-switched autoantibody (autoAb) production in BAFF transgenic mice. Consistent with this finding, a subset of transitional splenic B cells upregulate surface TACI expression and contribute to BAFF-driven autoAb. In the current study, we interrogated the B cell signals required for transitional B cell TACI expression and Ab production. Surprisingly, despite established roles for dual BCR and TLR signals in autoAb production in SLE, signals downstream of these receptors exerted distinct impacts on transitional B cell TACI expression and autoAb titers. Whereas loss of BCR signals prevented transitional B cell TACI expression and resulted in loss of serum autoAb across all Ig isotypes, lack of TLR signals exerted a more limited impact restricted to autoAb class-switch recombination without altering transitional B cell TACI expression. Finally, in parallel with the protective effect of TACI deletion, loss of BAFF-R signaling also protected against BAFF-driven autoimmunity. Together, these findings highlight how multiple signaling pathways integrate to promote class-switched autoAb production by transitional B cells, events that likely impact the pathogenesis of SLE and other BAFF-dependent autoimmune diseases.


Assuntos
Autoanticorpos/metabolismo , Glomerulonefrite por IGA/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Glicoproteínas de Membrana/metabolismo , Células Precursoras de Linfócitos B/fisiologia , Receptores de Antígenos de Linfócitos B/metabolismo , Receptor 7 Toll-Like/metabolismo , Animais , Fator Ativador de Células B/genética , Fator Ativador de Células B/metabolismo , Receptor do Fator Ativador de Células B/genética , Modelos Animais de Doenças , Humanos , Switching de Imunoglobulina , Ativação Linfocitária , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptor Cross-Talk , Receptores de Antígenos de Linfócitos B/genética , Transdução de Sinais , Receptor 7 Toll-Like/genética , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Proteína Transmembrana Ativadora e Interagente do CAML/metabolismo
15.
Front Immunol ; 9: 2125, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30333819

RESUMO

TACI signals activate B cell proliferation, isotype switch and antibody production in both normal immunity and autoimmune states. In contrast to murine TACI, the human TACI gene undergoes alternative splicing to produce short and long isoforms (TACI-S and TACI-L). In previous studies, we showed that transduction of the short, but not long isoform, into murine B cells or human pre-B cells lacking TACI, caused them to become transcriptional and morphologically identical to plasma cells. These data suggest that the expression of different isoforms in humans provides unique controls on B cell maturation. In these studies we show that TACI-S and TACI-L form complexes in a ligand-independent manner, not dependent on a single extracellular domain. Both TACI isoforms are detectable in the endosomal cellular compartment where they co-localize with MyD88, TRAF6, and the activated 65 kDa form of TLR9, depending on a conserved intracellular TACI sequence. In contrast to TACI-L expressing cells, or cells bearing both isoforms, TACI-S binds ligands BAFF and APRIL with substantially greater affinity and promotes enhanced NF-kB activation. Using isoform-specific monoclonal antibodies, we show that while TACI-L is predominant as a surface receptor surface on human B cells, significantly more TACI-S is noted in the intracellular compartment and also in marginal zone, isotype switched and plasmablast in resting B cells. TACI-S is increased in tonsillar B cells and also in the intracellular compartment of activated peripheral B cells. These data shows that alternative splicing of the human TACI gene leads to two isoforms both of which intersect with MyD88 and TRAF6 and form complexes with TLR9, but the two isoforms have different ligand binding capacities, subcellular locations and activation capabilities.


Assuntos
Fator Ativador de Células B/imunologia , Plasmócitos/imunologia , Proteína Transmembrana Ativadora e Interagente do CAML/imunologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Animais , Fator Ativador de Células B/genética , Humanos , Camundongos , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Plasmócitos/citologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/imunologia , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/imunologia , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética
16.
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
17.
Semin Nephrol ; 38(5): 513-520, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30177023

RESUMO

IgA nephropathy (IgAN) is the most common form of primary glomerulonephritis in the world. IgAN is characterized by mesangial deposits of IgA1-containing immune complexes. IgA1 usually co-deposits with complement C3 and variable IgG and/or IgM. Exactly 50 years have passed since IgAN was described, however, the pathogenesis of disease onset and progression have not been fully clarified. Animal models can re-create the complex immunologic microenvironments that foster human autoimmunity and nephritis and provide access to tissue compartments not readily examined in patients. Thus, multiple models that may be helpful in studies of specific aspects of IgAN have been developed. A unique spontaneous animal model of IgAN, the ddY mouse, was reported in 1985. These mice show mild proteinuria and glomerular IgA deposits, with a highly variable incidence and degree of glomerular injury owing to a heterogeneous genetic background. Thus, we intercrossed an early onset group of ddY mice in which the development of IgAN resulted in the establishment of a novel 100% early onset-grouped ddY mouse model with increased levels of aberrantly glycosylated IgA and immune complexes. Although the molecular features of human IgA1 are different from rodent IgA, human IgA1 knock-in (α1KI)-CD89 transgenic mice, which express both human IgA1 and CD89, show circulating and mesangial deposits of IgA1-soluble CD89 complexes that result in kidney inflammation, hematuria, and proteinuria. In this review, we introduce several murine models of IgAN that can be useful tools for the analysis of multiple aspects of the pathogenesis of IgAN, which may aid in the assessment of approaches for the treatment of IgAN.


Assuntos
Antígenos CD/genética , Modelos Animais de Doenças , Glomerulonefrite por IGA/genética , Imunoglobulina A/genética , Camundongos , Receptores Fc/genética , Animais , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Galactose/metabolismo , Técnicas de Introdução de Genes , Glomerulonefrite por IGA/imunologia , Glicosilação , Hematúria/genética , Hematúria/imunologia , Humanos , Imunoglobulina A/metabolismo , Lactalbumina/imunologia , Camundongos Endogâmicos , Camundongos Knockout , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/imunologia , Nefrite/genética , Nefrite/imunologia , Proteinúria/genética , Proteinúria/imunologia , Receptores Fc/imunologia , Vírus Sendai/imunologia , Receptor Toll-Like 9/imunologia , Tricotecenos/imunologia , Uteroglobina/genética
18.
Sci Rep ; 8(1): 11209, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-30046058

RESUMO

Previously, we reported that Zika virus (ZIKV) causes ocular complications such as chorioretinal atrophy, by infecting cells lining the blood-retinal barrier, including the retinal pigment epithelium (RPE). To understand the molecular basis of ZIKV-induced retinal pathology, we performed a meta-analysis of transcriptome profiles of ZIKV-infected human primary RPE and other cell types infected with either ZIKV or other related flaviviruses (Japanese encephalitis, West Nile, and Dengue). This led to identification of a unique ZIKV infection signature comprising 43 genes (35 upregulated and 8 downregulated). The major biological processes perturbed include SH3/SH2 adaptor activity, lipid and ceramide metabolism, and embryonic organ development. Further, a comparative analysis of some differentially regulated genes (ABCG1, SH2B3, SIX4, and TNFSF13B) revealed that ZIKV induced their expression relatively more than dengue virus did in RPE. Importantly, the pharmacological inhibition of ABCG1, a membrane transporter of cholesterol, resulted in reduced ZIKV infectivity. Interestingly, the ZIKV infection signature revealed the downregulation of ALDH5A1 and CHML, genes implicated in neurological (cognitive impairment, expressive language deficit, and mild ataxia) and ophthalmic (choroideremia) disorders, respectively. Collectively, our study revealed that ZIKV induces differential gene expression in RPE cells, and the identified genes/pathways (e.g., ABCG1) could potentially contribute to ZIKV-associated ocular pathologies.


Assuntos
Epitélio Pigmentado da Retina/metabolismo , Transcriptoma/genética , Infecção por Zika virus/genética , Zika virus/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Fator Ativador de Células B/genética , Dengue/genética , Dengue/patologia , Dengue/virologia , Vírus da Dengue/patogenicidade , Vírus da Encefalite Japonesa (Subgrupo)/patogenicidade , Infecções por Flavivirus/genética , Infecções por Flavivirus/patologia , Infecções por Flavivirus/virologia , Regulação da Expressão Gênica/genética , Proteínas de Homeodomínio/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Cultura Primária de Células , Proteínas/genética , Epitélio Pigmentado da Retina/patologia , Epitélio Pigmentado da Retina/virologia , Transativadores/genética , Replicação Viral/genética , Febre do Nilo Ocidental/genética , Febre do Nilo Ocidental/patologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/patogenicidade , Zika virus/patogenicidade , Infecção por Zika virus/patologia , Infecção por Zika virus/virologia
19.
Clin Immunol ; 197: 19-26, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30056130

RESUMO

B-cell activating factor (BAFF) has been proposed to play a crucial role in the pathogenesis of chronic rhinosinusitis with nasal polyp (CRSwNP). The aim of this study was to evaluate the role of toll-like receptor (TLR) 9-mediated BAFF activation on the pathogenesis of CRSwNP. NP and uncinate tissue (UT) were obtained from patients with CRSwNP or CRS without NP, and control subjects. The expression of TLR9, high mobility group box-1 protein (HMGB1), type I interferon (IFN), BAFF, and anti-double stranded DNA (dsDNA) antibody were examined in the tissues and the cultured dispersed NP cells (DNPCs). The expression of TLR9, HMGB1, type I IFN, BAFF, and anti-dsDNA antibody were elevated in NP tissue compared to the UTs. Exposure to TLR9 agonist increased the type I IFN expression in vitro, which further increased BAFF production. In conclusion, we provided a novel therapeutic potential of TLR9 agonist in CRSwNP.


Assuntos
Fator Ativador de Células B/genética , Proteína HMGB1/genética , Pólipos Nasais/metabolismo , Rinite/metabolismo , Sinusite/metabolismo , Receptor Toll-Like 9/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Fator Ativador de Células B/efeitos dos fármacos , Fator Ativador de Células B/metabolismo , Doença Crônica , Feminino , Seio Frontal/metabolismo , Proteína HMGB1/metabolismo , Humanos , Técnicas In Vitro , Interferon-alfa/efeitos dos fármacos , Interferon-alfa/genética , Interferon-alfa/metabolismo , Interferon beta/efeitos dos fármacos , Interferon beta/genética , Interferon beta/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Receptor Toll-Like 9/agonistas
20.
J Autoimmun ; 92: 87-92, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29859654

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a chronic systemic autoimmune disease with an increased atherosclerotic risk compared to healthy population, partially explained by traditional cardiovascular (CV) risk factors. Recent data suggest B-cell activating factor (BAFF) as an important contributor in the pathogenesis of both SLE and atherosclerosis. The aim of the current study is to explore whether serum BAFF levels along with variants of the BAFF gene increase lupus related atherosclerotic risk. PATIENTS-METHODS: 250 SLE patients underwent assessment of plaque formation and/or intimal media thickness (IMT) measurements in carotid and femoral arteries by ultrasound. Disease related features and CV traditional risk factors were also assessed. Serum BAFF levels were determined by commercially available ELISA and five single nucleotide polymorphisms (SNPs) of the BAFF gene (rs1224141, rs12583006, rs9514828, rs1041569 and the rs9514827) were evaluated by PCR-based assays in all patients and 200 healthy controls (HC) of similar age and sex distribution. SLE patients were further divided in high and low BAFF groups on the basis of the upper quartile level of the distribution (1358 pg/ml). Genotype and haplotype frequencies in SLE patients and HC were determined by SNPStats and SHEsis software. RESULTS: High-BAFF SLE group displayed increased rates of both plaque formation and arterial wall thickening (defined as IMT>0.90 mm) compared to patients with low BAFF levels (58.1% vs 43.6%, p:0.048 and 38.6% vs 23.2%, p-value: 0.024, respectively). The association remained significant after disease related features were taken into account (ORs [95%CI]: 2.2 [1.0-5.1] and 2.5 [1.1-5.5] for plaque formation and arterial wall thickening, respectively). Moreover, the presence of the AA genotype of the rs12583006 BAFF gene variant increased susceptibility for both lupus and lupus related plaque formation (ORs [95%CI]: 2.8 [1.1-7.1], and 4.4 [1.3-15.4] in the codominant model, respectively). Finally, the haplotype TTTAT was found to be protective for plaque formation among SLE patients (OR 0.3 [0.1-0.9]. No associations between BAFF gene variants with arterial wall thickening were detected. CONCLUSIONS: High BAFF serum levels in the upper 4th quartile as well as BAFF genetic variants seem to increase susceptibility for both lupus and lupus related subclinical atherosclerosis implying B-cell hyperactivity as a potential contributor in the pronounced lupus related atherosclerotic risk.


Assuntos
Aterosclerose/genética , Fator Ativador de Células B/genética , Linfócitos B/imunologia , Genótipo , Lúpus Eritematoso Sistêmico/genética , Adulto , Idoso , Aterosclerose/epidemiologia , Fator Ativador de Células B/sangue , Espessura Intima-Media Carotídea , Feminino , Frequência do Gene , Predisposição Genética para Doença , Grécia/epidemiologia , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Risco
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