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1.
Life Sci ; 231: 116688, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31348950

RESUMO

The extended infection with Helicobacter pylori (H. pylori), one of the most frequent infectious agents in humans, may cause gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. During H. pylori infection, different kinds of inflammatory cells such as dendritic cells, macrophages, neutrophils, mast cells, eosinophils, T cells and B cells are accumulated into the stomach. The interactions between chemokines and their respective receptors recruit particular types of the leukocytes that ultimately determine the nature of immune response and therefore, have a main influence on the consequence of infection. The suitable production of chemokines especially in the early stages of H. pylori infection shapes appropriate immune responses that contribute to the H. pylori elimination. The unbalanced expression of the chemokines can contribute in the induction of inappropriate responses that result in the tissue damage or malignancy. Thus, chemokines and their receptors may be promising potential targets for designing the therapeutic strategies against various types H. pylori-related gastrointestinal disorders. In this review, a comprehensive explanation regarding the roles played by chemokines in H. pylori-mediated peptic ulcer, gastritis and gastric malignancies was provided while presenting the potential utilization of these chemoattractants as therapeutic elements.


Assuntos
Quimiocinas/metabolismo , Quimiocinas/farmacologia , Infecções por Helicobacter/terapia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Quimiocinas CXC/imunologia , Quimiocinas CXC/metabolismo , Mucosa Gástrica/metabolismo , Gastrite , Infecções por Helicobacter/complicações , Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Helicobacter pylori/metabolismo , Helicobacter pylori/patogenicidade , Humanos , Receptores CXCR/imunologia , Receptores CXCR/metabolismo , Receptores de Quimiocinas/imunologia , Receptores de Quimiocinas/metabolismo , Estômago/patologia , Neoplasias Gástricas/patologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
2.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(5): 425-433, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31223112

RESUMO

Objective To investigate the expression and clinical significance of whey acidic protein (WAP) 4-disulfide core domain 2/human epididymis protein 4 (WFDC2/HE4) in lung adenocarcinoma. Methods The expression of WFDC2 in normal lung tissues and lung adenocarcinoma tissues, the correlation between WFDC2 and the prognosis survival in patients with lung adenocarcinoma were analyzed using the BioGPS database, GEPIA database, Oncomine database and Kaplan-Meier Plotter databases. The expression of WFDC2 in cancer tissue T cells and B cells was analyzed using the Cancer Cell Line Encyclopedia (CCLE). The WFDC2-related genes and functional annotations of their gene ontology (GO), the pathway enrichment of Kyoto Gene and Genomic Encyclopedia (KEGG) were analyzed using the STRING database. The co-expression relationship, correlation and significance of WFDC2-related genes in lung adenocarcinoma were analyzed using the cBioPortal database. The expression of WFDC2 in immune infiltrates and its implication to survival prognosis in the patients with lung adenocarcinoma were analyzed using the Tumor Immune Estimation Resource (TIMER) database. Results BioGPS database analysis showed that the expression of WFDC2 was low in normal lung tissues, but none in T cells and B cells of normal human tissues. GEPIA database analysis showed that the expression of WFDC2 was higher in lung adenocarcinoma compared with normal lung tissues. Four hundred and fourteen samples of differential expression of WFDC2 were obtained from Oncomine database. Nineteen of them had increased WFDC2 expression with four in lung adenocarcinoma; fifteen of them had decreased WFDC2 expression with one in lung adenocarcinoma. Meta-analysis of 4 studies meeting the setting conditions showed that the expression level of WFDC2 was high in lung adenocarcinoma tissues. Kaplan-Meier Plotter database results showed that the overall survival (OS) time of patients with lung adenocarcinoma in the high WFDC2 expression group was significantly longer than that in the low WFDC2 expression group. CCLE analysis showed that the expression of WFDC2 in cancer tissue T cells and B cells was significantly higher than that in normal tissues. String database analysis showed that there were 30 genes associated with WFDC2, which were involved in 4 signaling pathways. The classification results from GO annotation indicated the enrichment in 4 cell components, 8 molecular functions, and 27 biological processes. The cBioPortal database showed that the correlation and difference between secretory leukocyte protease inhibitor (SLPI) and WFDC2 in lung adenocarcinoma were markedly significant (Pearson=0.26; Spearman=0.46; P=6.20E-28). TIMER database analysis showed that B cells with high expression of WFDC2 in the immune microenvironment significantly prolonged the survival prognosis of patients with lung adenocarcinoma for 1 year, 3 years, 5 years and 10 years. Conclusion WFDC2 is highly expressed in lung adenocarcinoma tissues with the anti-tumor immunosuppressive effect, which can significantly prolong OS of lung adenocarcinoma patients and be used as a candidate marker for investigating clinical prognosis of lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão/genética , Linfócitos B/metabolismo , Neoplasias Pulmonares/genética , Proteínas/genética , Taxa de Sobrevida , Humanos , Prognóstico , Linfócitos T , Microambiente Tumoral
3.
Nat Commun ; 10(1): 2771, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235807

RESUMO

Diverse antibody repertoires are generated through remote genomic interactions involving immunoglobulin variable (VH), diversity (DH) and joining (JH) gene segments. How such interactions are orchestrated remains unknown. Here we develop a strategy to track VH-DHJH motion in B-lymphocytes. We find that VH and DHJH segments are trapped in configurations that allow only local motion, such that spatially proximal segments remain in proximity, while spatially remote segments remain remote. Within a subset of cells, however, abrupt changes in VH-DHJH motion are observed, plausibly caused by temporal alterations in chromatin configurations. Comparison of experimental and simulated data suggests that constrained motion is imposed by a network of cross-linked chromatin chains characteristic of a gel phase, yet poised near the sol phase, a solution of independent chromatin chains. These results suggest that chromosome organization near the sol-gel phase transition dictates the timing of genomic interactions to orchestrate gene expression and somatic recombination.


Assuntos
Cromatina/metabolismo , Cromossomos/metabolismo , Regulação da Expressão Gênica/fisiologia , Genes de Imunoglobulinas/genética , Recombinação V(D)J/fisiologia , Animais , Linfócitos B/metabolismo , Linhagem Celular , Cromossomos/genética , Proteínas de Ligação a DNA/deficiência , Genômica , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/metabolismo , Camundongos , Transição de Fase
4.
Nat Immunol ; 20(7): 852-864, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31213723

RESUMO

Dendritic cells (DC) are currently classified as conventional DCs (cDCs) and plasmacytoid DCs (pDCs). Through a combination of single-cell transcriptomic analysis, mass cytometry, in vivo fate mapping and in vitro clonal assays, here we show that, at the single-cell level, the priming of mouse hematopoietic progenitor cells toward the pDC lineage occurs at the common lymphoid progenitor stage, indicative of early divergence of the pDC and cDC lineages. We found the transcriptional signature of a pDC precursor stage, defined here, in the IL-7Rα+ common lymphoid progenitor population and identified Ly6D, IL-7Rα, CD81 and CD2 as key markers of pDC differentiation, which distinguish pDC precursors from cDC precursors. In conclusion, pDCs developed in the bone marrow from a Ly6DhiCD2hi lymphoid progenitor cell and differentiated independently of the myeloid cDC lineage.


Assuntos
Antígenos Ly/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Células Progenitoras Linfoides/citologia , Células Progenitoras Linfoides/metabolismo , Células Progenitoras Mieloides/citologia , Células Progenitoras Mieloides/metabolismo , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Citometria de Fluxo , Proteínas Ligadas por GPI/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Camundongos , Transcriptoma
5.
Nat Commun ; 10(1): 2201, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101814

RESUMO

Systemic lupus erythematosus (SLE) is the prototypic systemic autoimmune disease. It is thought that many common variant gene loci of weak effect act additively to predispose to common autoimmune diseases, while the contribution of rare variants remains unclear. Here we describe that rare coding variants in lupus-risk genes are present in most SLE patients and healthy controls. We demonstrate the functional consequences of rare and low frequency missense variants in the interacting proteins BLK and BANK1, which are present alone, or in combination, in a substantial proportion of lupus patients. The rare variants found in patients, but not those found exclusively in controls, impair suppression of IRF5 and type-I IFN in human B cell lines and increase pathogenic lymphocytes in lupus-prone mice. Thus, rare gene variants are common in SLE and likely contribute to genetic risk.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Proteínas de Membrana/genética , Quinases da Família src/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adolescente , Adulto , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Estudos de Casos e Controles , Linhagem Celular , Núcleo Celular/imunologia , Núcleo Celular/metabolismo , Criança , Modelos Animais de Doenças , Feminino , Frequência do Gene , Células HEK293 , Voluntários Saudáveis , Humanos , Fatores Reguladores de Interferon/imunologia , Fatores Reguladores de Interferon/metabolismo , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação de Sentido Incorreto , Sequenciamento Completo do Exoma , Quinases da Família src/metabolismo
6.
An Acad Bras Cienc ; 91(2): e20180941, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31141015

RESUMO

The aim of this study was to investigate the inhibitory effect of regulation of miR-122-MAP3K2 signal pathway on the hepatitis B cells. We detected the content of MAP3K2 from patients with HBV blood serum samples and analyzed the correlation between content of MAP3K2 and copies of HBV-DNA. Wound healing and Transwell assays were used to detect the function of cells from control group (wild type) and observer group (overexpresses miR-122). Secretion levels of HBsAg and MAP3K2 in the supernatant and level of MAP3K2 in cells were detected by ELISA and western blot, respectively. The results showed that there was a positive correlation between the copies of HBV-DNA and MAP3K2 in serum. In the assays involving detection of the number of HBV-DNA copies, the supernatant levels of HBsAg and MAP3K2, and the level of MAP3K2 in the cells, the rate of increase of these indicators significantly slowed as culture time. In conclusion, overexpression of miR-122 could inhibit the migration of hepatoblastoma cells; however, following transfection with miR-122, DNA synthesis and the secretion of HBsAg were inhibited. Overexpression of miR-122 can also downregulate MAP3K2. Consequently, we concluded that regulating the miR-122-MAP3K2 signaling pathway exerts an inhibitory effect in hepatitis B cells.


Assuntos
Linfócitos B/metabolismo , Vírus da Hepatite B/genética , Hepatite B/metabolismo , MAP Quinase Quinase Quinases/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais/genética , Western Blotting , DNA Viral/genética , Ensaio de Imunoadsorção Enzimática , Hepatite B/patologia , Humanos , MAP Quinase Quinase Quinases/genética , MicroRNAs/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
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
8.
Nat Commun ; 10(1): 2153, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31089128

RESUMO

The gut commensal Bacteroides fragilis or its capsular polysaccharide A (PSA) can prevent various peripheral and CNS sterile inflammatory disorders. Fatal herpes simplex encephalitis (HSE) results from immune pathology caused by uncontrolled invasion of the brainstem by inflammatory monocytes and neutrophils. Here we assess the immunomodulatory potential of PSA in HSE by infecting PSA or PBS treated 129S6 mice with HSV1, followed by delayed Acyclovir (ACV) treatment as often occurs in the clinical setting. Only PSA-treated mice survived, with dramatically reduced brainstem inflammation and altered cytokine and chemokine profiles. Importantly, PSA binding by B cells is essential for induction of regulatory CD4+ and CD8+ T cells secreting IL-10 to control innate inflammatory responses, consistent with the lack of PSA mediated protection in Rag-/-, B cell- and IL-10-deficient mice. Our data reveal the translational potential of PSA as an immunomodulatory symbiosis factor to orchestrate robust protective anti-inflammatory responses during viral infections.


Assuntos
Bacteroides fragilis/imunologia , Encefalite por Herpes Simples/imunologia , Microbioma Gastrointestinal/imunologia , Herpesvirus Humano 1/imunologia , Polissacarídeos Bacterianos/imunologia , Aciclovir/uso terapêutico , Animais , Antivirais/uso terapêutico , Linfócitos B/imunologia , Linfócitos B/metabolismo , Bacteroides fragilis/metabolismo , Cercopithecus aethiops , Modelos Animais de Doenças , Encefalite por Herpes Simples/tratamento farmacológico , Encefalite por Herpes Simples/virologia , Feminino , Herpesvirus Humano 1/patogenicidade , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-10/metabolismo , Masculino , Camundongos , Camundongos Knockout , Polissacarídeos Bacterianos/metabolismo , Simbiose/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Células Vero
9.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(2): 162-168, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30975282

RESUMO

Objective To detect the levels of cell-bound complement activation product (C4d) and immunoglobulins (IgG and IgM) on T and B lymphocytes in patients with systemic lupus erythematosus (SLE), and to evaluate the relationships between C4d and immunoglobulins (Ig) on lymphocytes, and finally to evaluate their diagnostic value for SLE. Methods A cross-sectional study including 142 SLE patients, 144 patients with other non-SLE autoimmune diseases and 100 healthy individuals was conducted. C4d and immunoglobulins on peripheral T and B lymphocytes (T-C4d, B-C4d, T-Ig and B-Ig) were measured by flow cytometry. In vitro immunobinding experiment was performed to characterize serum Ig from SLE patients to generate T-C4d, B-C4d, T-Ig and B-Ig. ANA, anti-dsDNA, anti-Smith antibody and other biomarkers were measured. Area under the receiver operating characteristic curve (AUC), nonparametric tests, partial correlation analysis, sensitivity and specificity were used for statistical analysis. Results Levels of T-C4d, B-C4d, T-Ig and B-Ig were found to be highest in SLE patients. Levels of T-C4d, B-C4d, T-Ig and B-Ig in non-SLE patients were also significantly higher than those in healthy individuals. T-C4d was positively correlated with T-Ig (r=0.587), as well as B-C4d vs B-Ig (r=0.734). Purified Ig from SLE plasma generated higher levels of T-C4d, B-C4d, T-Ig and B-Ig than Ig-removed SLE plasma. AUC of T-C4d, B-C4d, T-Ig and B-Ig were 0.733, 0.834, 0.707 and 0.825, respectively. Compared with anti-dsDNA antibody (38.7%), the sensitivity for SLE diagnosis increased significantly when the combination of T-C4d, B-C4d, T-Ig and B-Ig (85.2%) was made. Conclusion The autoantibody is a key factor for cell-bound C4d formation, and T-C4d, B-C4d, T-Ig and B-Ig may be reliable indicators for the diagnosis of SLE.


Assuntos
Complexo Antígeno-Anticorpo , Complemento C4b , Imunoglobulinas , Lúpus Eritematoso Sistêmico , Complexo Antígeno-Anticorpo/metabolismo , Linfócitos B/metabolismo , Complemento C4b/metabolismo , Estudos Transversais , Testes Diagnósticos de Rotina/normas , Humanos , Imunoglobulinas/metabolismo , Lúpus Eritematoso Sistêmico/diagnóstico , Sensibilidade e Especificidade , Linfócitos T/metabolismo
10.
Int J Mol Sci ; 20(8)2019 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-31013925

RESUMO

The etiology of Kawasaki disease (KD), the leading cause of acquired heart disease in children, is currently unknown. Epidemiology supports a relationship of KD to an infectious disease. Several pathological mechanisms are being considered, including a superantigen response, direct invasion by an infectious etiology or an autoimmune phenomenon. Treating affected patients with intravenous immunoglobulin is effective at reducing the rates of coronary aneurysms. However, the role of B cells and antibodies in KD pathogenesis remains unclear. Murine models are not clear on the role for B cells and antibodies in pathogenesis. Studies on rare aneurysm specimens reveal plasma cell infiltrates. Antibodies generated from these aneurysmal plasma cell infiltrates showed cross-reaction to intracellular inclusions in the bronchial epithelium of a number of pathologic specimens from children with KD. These antibodies have not defined an etiology. Notably, a number of autoantibody responses have been reported in children with KD. Recent studies show acute B cell responses are similar in children with KD compared to children with infections, lending further support of an infectious disease cause of KD. Here, we will review and discuss the inconsistencies in the literature in relation to B cell responses, specific antibodies, and a potential role for humoral immunity in KD pathogenesis or diagnosis.


Assuntos
Anticorpos/imunologia , Linfócitos B/imunologia , Síndrome de Linfonodos Mucocutâneos/etiologia , Animais , Formação de Anticorpos/imunologia , Autoanticorpos/imunologia , Autoimunidade , Linfócitos B/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Humanos , Imunidade Humoral , Ativação Linfocitária/imunologia , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Síndrome de Linfonodos Mucocutâneos/metabolismo
11.
Life Sci ; 227: 153-165, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31004657

RESUMO

AIMS: Alantolactone (ALT) is active component of natural product Inula helenium with a lot of pharmacological effects, including anti-tumor effect. The present work aimed to explore the antitumor effect of ALT in B cell acute lymphoblastic leukemia (B-ALL). MAIN METHODS: B-ALL cells were treated with various concentrations of ALT, and then trypan blue assay, Annexin V/PI staining assay, PI staining assay, western blot analysis were employed to measure the effect of ALT on viability, apoptosis and cell cycle in B-ALL cells. In addition, a synthetic bioinformatics method was used to predict the underlying mechanism of antitumor effect of ALT. Then Reactive Oxygen Species (ROS) probe Dihydroethidium (DHE) and 2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA) were used to detect accumulation of cellular ROS. Meanwhile, DNA damage was identified by 8-oxoG, p-ATM1987, γ-H2AX and comet assay. In addition, activity of glutathione reductase (GR), thioredoxin reductase (TrxR) and catalase were measured and overexpressed in SEM and RS4;11 cells to study the inhibition on these enzymes. Finally, B-ALL NOD-SCID mouse model was used to test its performance in vivo. KEY FINDINGS: ALT showed good antitumor effect in B-ALL in vivo and in vitro through inducing ROS overload, which led to DNA damage. In addition, we found ROS overload caused by ALT was due to its direct inhibition on reductase. SIGNIFICANCE: We found that ALT, a natural product, showing a promising tactic in the therapy of B-ALL by targeting ROS pathway.


Assuntos
Lactonas/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Sesquiterpenos de Eudesmano/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Lactonas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mitocôndrias/efeitos dos fármacos , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos de Eudesmano/metabolismo
12.
J Cancer Res Clin Oncol ; 145(6): 1437-1448, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30941572

RESUMO

PURPOSE: Despite considerable evidence that supports the NF-kB role in the immune system and lymphomagenesis, it is unclear whether specific NF-kB dimers control a particular set of genes that account for their biological functions. Our previous work showed that Hodgkin Lymphoma (HL) is unique, among germinal center (GC)-derived lymphomas, with respect to its dependency on Rel-B to survive. In contrast, diffuse large B-Cell lymphoma (DLBCL) including both Activated B-Cell-Like and Germinal Center B-Cell-Like, requires cREL and Rel-A to survive and it is not affected by Rel-B depletion. These findings highlighted the activity of specific NF-kB subunits in different GC-derived lymphomas. METHODS: Sequenced chromatin immunoprecipitated DNA fragments (ChIP-Seq) analysis revealed an extensive NF-kB DNA-binding network in DLBCL and HL. The ChIP-Seq data was merged with microarray analysis following the Rel-A, Rel-B or cRel knockdown to determine effectively regulated genes. RESULTS: Downstream target analysis showed enrichment for cell cycle control, among other signatures. Rel-B and cRel controlled different genes within the same signature in HL and DLBCL, respectively. BCL2 was exclusively controlled by Rel-B in HL. Both mRNA and protein levels decreased following Rel-B depletion meanwhile there was no change upon cRel knock-down. BCL2 exogenous expression partially rescued the death induced by decreased Rel-B in HL cells. CONCLUSION: The Rel-B hierarchical network defined HL and the cRel hierarchical network characterized DLBCL. Each Rel member performs specific functions in distinct GC-derived lymphomas. This result should be considered for the development of targeted therapies that are aimed to selectively inhibit individual NF-kB dimers.


Assuntos
DNA de Neoplasias/metabolismo , Doença de Hodgkin/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , NF-kappa B/metabolismo , Apoptose/genética , Linfócitos B/metabolismo , Linfócitos B/patologia , Linhagem Celular Tumoral , DNA de Neoplasias/genética , Perfilação da Expressão Gênica , Células HEK293 , Doença de Hodgkin/genética , Humanos , Linfoma Difuso de Grandes Células B/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-rel/genética , Proteínas Proto-Oncogênicas c-rel/metabolismo , Transdução de Sinais , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelB/genética , Fator de Transcrição RelB/metabolismo , Transcrição Genética
13.
Nat Commun ; 10(1): 1823, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015452

RESUMO

Granulomas are the pathological hallmark of tuberculosis (TB) and the niche where bacilli can grow and disseminate or the immunological microenvironment in which host cells interact to prevent bacterial dissemination. Here we show 34 immune transcripts align to the morphology of lung sections from Mycobacterium tuberculosis-infected mice at cellular resolution. Colocalizing transcript networks at <10 µm in C57BL/6 mouse granulomas increase complexity with time after infection. B-cell clusters develop late after infection. Transcripts from activated macrophages are enriched at subcellular distances from M. tuberculosis. Encapsulated C3HeB/FeJ granulomas show necrotic centers with transcripts associated with immunosuppression (Foxp3, Il10), whereas those in the granuloma rims associate with activated T cells and macrophages. We see highly diverse networks with common interactors in similar lesions. Different immune landscapes of M. tuberculosis granulomas depending on the time after infection, the histopathological features of the lesion, and the proximity to bacteria are here defined.


Assuntos
Linfócitos B/imunologia , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculoma/imunologia , Tuberculose Pulmonar/imunologia , Animais , Linfócitos B/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-10/metabolismo , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/metabolismo , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/isolamento & purificação , RNA Mensageiro/isolamento & purificação , Fatores de Tempo , Tuberculoma/microbiologia , Tuberculoma/patologia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia
14.
Nat Immunol ; 20(6): 736-746, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31011187

RESUMO

B cell antigen receptor (BCR) and CD40 signaling are rewired in germinal center (GC) B cells (GCBCs) to optimize selection for high-affinity B cells. In GCBC, BCR signals are constrained, but the mechanisms are not well understood. Here we describe a GC-specific, AKT-kinase-driven negative feedback loop that attenuates BCR signaling. Mass spectrometry revealed that AKT target activity was altered in GCBCs compared with naive B cells. Retargeting was linked to differential AKT T308 and S473 phosphorylation, in turn controlled by GC-specific upregulation of phosphoinositide-dependent protein kinase PDK1 and the phosphatase PTEN. In GCBCs, AKT preferentially targeted CSK, SHP-1 and HPK1, which are negative regulators of BCR signaling. We found that phosphorylation enhances enzymatic activity of these proteins, creating a negative feedback loop that dampens upstream BCR signaling. AKT inhibition relieved this negative feedback and enhanced activation of BCR-proximal kinase LYN, as well as downstream BCR signaling molecules in GCBCs.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Centro Germinativo/imunologia , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Animais , Biomarcadores , Biologia Computacional/métodos , Ativação Enzimática , Técnicas de Inativação de Genes , Humanos , Camundongos Knockout , Fosforilação , Especificidade por Substrato
15.
Nat Commun ; 10(1): 1874, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015400

RESUMO

Cancer evolution is fueled by epigenetic as well as genetic diversity. In chronic lymphocytic leukemia (CLL), intra-tumoral DNA methylation (DNAme) heterogeneity empowers evolution. Here, to comprehensively study the epigenetic dimension of cancer evolution, we integrate DNAme analysis with histone modification mapping and single cell analyses of RNA expression and DNAme in 22 primary CLL and 13 healthy donor B lymphocyte samples. Our data reveal corrupted coherence across different layers of the CLL epigenome. This manifests in decreased mutual information across epigenetic modifications and gene expression attributed to cell-to-cell heterogeneity. Disrupted epigenetic-transcriptional coordination in CLL is also reflected in the dysregulation of the transcriptional output as a function of the combinatorial chromatin states, including incomplete Polycomb-mediated gene silencing. Notably, we observe unexpected co-mapping of typically mutually exclusive activating and repressing histone modifications, suggestive of intra-tumoral epigenetic diversity. Thus, CLL epigenetic diversification leads to decreased coordination across layers of epigenetic information, likely reflecting an admixture of cells with diverging cellular identities.


Assuntos
Linfócitos B/metabolismo , Cromatina/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/genética , Metilação de DNA , Evolução Molecular , Inativação Gênica , Genes de Cadeia Pesada de Imunoglobulina/genética , Voluntários Saudáveis , Código das Histonas/genética , Histonas/genética , Histonas/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/sangue , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Regiões Promotoras Genéticas/genética , Análise de Sequência de RNA , Análise de Célula Única/métodos , Sequenciamento Completo do Exoma
16.
Mol Cell ; 74(4): 701-712.e9, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-30948266

RESUMO

Alternative 3' untranslated regions (3' UTRs) are widespread, but their functional roles are largely unknown. We investigated the function of the long BIRC3 3' UTR, which is upregulated in leukemia. The 3' UTR does not regulate BIRC3 protein localization or abundance but is required for CXCR4-mediated B cell migration. We established an experimental pipeline to study the mechanism of regulation and used mass spectrometry to identify BIRC3 protein interactors. In addition to 3'-UTR-independent interactors involved in known BIRC3 functions, we detected interactors that bind only to BIRC3 protein encoded from the mRNA with the long 3' UTR. They regulate several functions, including CXCR4 trafficking. We further identified RNA-binding proteins differentially bound to the alternative 3' UTRs and found that cooperative binding of Staufen and HuR mediates 3'-UTR-dependent complex formation. We show that the long 3' UTR is required for the formation of specific protein complexes that enable additional functions of BIRC3 protein beyond its 3'-UTR-independent functions.


Assuntos
Proteína 3 com Repetições IAP de Baculovírus/genética , Leucemia/genética , Complexos Multiproteicos/genética , Receptores CXCR4/genética , Regiões 3' não Traduzidas/genética , Linfócitos B/metabolismo , Linfócitos B/patologia , Proteína 3 com Repetições IAP de Baculovírus/química , Movimento Celular/genética , Proteínas do Citoesqueleto/genética , Proteína Semelhante a ELAV 1/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia/patologia , Complexos Multiproteicos/química , Transporte Proteico , RNA Mensageiro/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética
17.
PLoS Genet ; 15(4): e1008101, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30946744

RESUMO

Class switch recombination (CSR) requires activation-induced cytidine deaminase (AID) to trigger DNA double strand breaks (DSBs) at the immunoglobulin heavy chain (IGH) in B cells. Joining of AID-dependent DSBs within IGH facilitate CSR and effective humoral immunity, but ligation to DSBs in non-IGH chromosomes leads to chromosomal translocations. Thus, the mechanism by which AID-dependent DSBs are repaired requires careful examination. The random activity of AID in IGH leads to a spectrum of DSB structures. In this report, we investigated how DSB structure impacts end-joining leading to CSR and chromosomal translocations in human B cells, for which models of CSR are inefficient and not readily available. Using CRISPR/Cas9 to model AID-dependent DSBs in IGH and non-IGH genes, we found that DSBs with 5' and 3' overhangs led to increased processing during end-joining compared to blunt DSBs. We observed that 5' overhangs were removed and 3' overhangs were filled in at recombination junctions, suggesting that different subsets of enzymes are required for repair based on DSB polarity. Surprisingly, while Cas9-mediated switching preferentially utilized NHEJ regardless of DSB structure, A-EJ strongly preferred repairing blunt DSBs leading to translocations in the absence of NHEJ. We found that DSB polarity influenced frequency of Cas9-mediated switching and translocations more than overhang length. Lastly, recombination junctions from staggered DSBs exhibited templated insertions, suggesting iterative resection and filling in during repair. Our results demonstrate that DSB structure biases repair towards NHEJ or A-EJ to complete recombination leading to CSR and translocations, thus helping to elucidate the mechanism of genome rearrangements in human B cells.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Quebras de DNA de Cadeia Dupla , Switching de Imunoglobulina , Translocação Genética , Sequência de Bases , Sistemas CRISPR-Cas , Linhagem Celular , Citidina Desaminase/metabolismo , Reparo do DNA por Junção de Extremidades/genética , Reparo do DNA por Junção de Extremidades/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Modelos Genéticos , Proteínas Proto-Oncogênicas c-bcl-6/genética , Recombinação Genética
18.
Mediators Inflamm ; 2019: 2473164, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30944545

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with the polyclonal activation of B lymphocytes and the production of autoantibodies that cause immune complex-related inflammation. Immunological factors derived from platelets modulate B cell function in SLE disease. However, platelets do not only modify the immune system by soluble factors. The binding of platelets to lymphocytes can modulate immune response. Thus, we speculate that the binding of platelets to lymphocytes in SLE patients may play a role in abnormal B lymphocyte response and the pathogenesis of SLE. We observed that levels of lymphocytes with bound platelets were higher in SLE patients than in healthy donors (HD). In SLE patients, the percentage of B lymphocytes with bound platelets positively correlated with plasmatic levels of IgG, IgA, IL-10, and soluble CD40L and negatively correlated with IgM levels, though not in HD. Preswitched memory B lymphocytes were the subpopulation with more bound platelets. Lymphocytes with bound platelets from both HD and SLE patients had major levels of CD86 and BAFFR and a greater production of IL-10 than lymphocytes without bound platelets. However, only B lymphocytes with bound platelets from SLE patients had increased levels of IgG and IgA on their surface. SLE patients with a suggestive renal manifestation had the highest levels of B and T lymphocytes with bound platelets. These results suggest that the binding of platelets to lymphocytes plays a role in SLE disease and that controlling this binding may be a promising therapeutic approach.


Assuntos
Linfócitos B/metabolismo , Linfócitos B/patologia , Plaquetas/metabolismo , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/patologia , Linfócitos/metabolismo , Linfócitos/patologia , Adulto , Ligante de CD40/sangue , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade
19.
Biomed Pharmacother ; 114: 108804, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30909146

RESUMO

B lymphocytes have been shown to contribute to autoimmune diseases via producing antibodies and proinflammatory cytokines. Depletion of B cells by blocking CD20 can inhibit these diseases. Here we examined whether an antibody against CD20, rituximab (RTX) (Rituxan@), used clinically in oncology could have similar anti-inflammatory effects in cardiac remodeling and heart failure (HF) in mice. Cardiac remodeling was established by pressure overload induced by transverse aortic constriction (TAC). Wild-type (WT) male C57BL/6 J mice were subjected to pressure overload by using transverse aortic constriction and then received RTX for 4 weeks. Administration of RTX markedly improves in vivo heart function, and suppressed heart chamber dilation, myocyte hypertrophy, fibrosis and oxidative stress in mice after TAC operation. RTX treatment also reversed established hypertrophic remodeling induced by TAC. Moreover, TAC-induced activation of multiple signaling pathways including calcineurin A, ERK1/2, STAT3, TGFß/Smad2/3 and IKKα/ß/NF-kB were remarkably attenuated in RTX-treated hearts compared with controls. These inhibitory effects of RTX were associated with inhibition of proinflammatory cytokine expression and Th2 cytokine-mediated IgG production from B cells. In conclusion, this study identifies that administration of RTX can inhibit pressure overload-induced cardiac remodeling and dysfunction in mice, and suggest that RTX may be a promising drug for treating hypertrophic disease.


Assuntos
Linfócitos B/efeitos dos fármacos , Coração/efeitos dos fármacos , Rituximab/farmacologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Antígenos CD20/metabolismo , Linfócitos B/metabolismo , Modelos Animais de Doenças , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Hipertrofia/tratamento farmacológico , Hipertrofia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
20.
Nature ; 567(7747): 244-248, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30842656

RESUMO

Germinal centres are important sites for antibody diversification and affinity maturation, and are also a common origin of B cell malignancies. Despite being made up of motile cells, germinal centres are tightly confined within B cell follicles. The cues that promote this confinement are incompletely understood. P2RY8 is a Gα13-coupled receptor that mediates the inhibition of migration and regulates the growth of B cells in lymphoid tissues1,2. P2RY8 is frequently mutated in germinal-centre B cell-like diffuse large B cell lymphoma (GCB-DLBCL) and Burkitt lymphoma1,3-6, and the ligand for this receptor has not yet been identified. Here we perform a search for P2RY8 ligands and find P2RY8 bioactivity in bile and in culture supernatants of several mouse and human cell lines. Using a seven-step biochemical fractionation procedure and a drop-out mass spectrometry approach, we show that a previously undescribed biomolecule, S-geranylgeranyl-L-glutathione (GGG), is a potent P2RY8 ligand that is detectable in lymphoid tissues at the nanomolar level. GGG inhibited the chemokine-mediated migration of human germinal-centre B cells and T follicular helper cells, and antagonized the induction of phosphorylated AKT in germinal-centre B cells. We also found that the enzyme gamma-glutamyltransferase-5 (GGT5), which was highly expressed by follicular dendritic cells, metabolized GGG to a form that did not activate the receptor. Overexpression of GGT5 disrupted the ability of P2RY8 to promote B cell confinement to germinal centres, which indicates that GGT5 establishes a GGG gradient in lymphoid tissues. This work defines GGG as an intercellular signalling molecule that is involved in organizing and controlling germinal-centre responses. As the P2RY8 locus is modified in several other types of cancer in addition to GCB-DLBCL and Burkitt lymphoma, we speculate that GGG might have organizing and growth-regulatory roles in multiple human tissues.


Assuntos
Linfócitos B/metabolismo , Receptores Purinérgicos P2Y/metabolismo , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Quimiocinas/imunologia , Feminino , Centro Germinativo/citologia , Centro Germinativo/imunologia , Humanos , Ligantes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tonsila Palatina/citologia , Tonsila Palatina/imunologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Purinérgicos P2Y/genética , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/imunologia , gama-Glutamiltransferase/metabolismo
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