Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 331
Filtrar
1.
Nat Immunol ; 20(9): 1244-1255, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31431722

RESUMO

Mucosal-associated invariant T cells (MAIT cells) recognize the microbial metabolite 5-(2-oxopropylideneamino)-6-D-ribitylaminouracil (5-OP-RU) presented by the MHC class Ib molecule, MR1. MAIT cells acquire effector functions during thymic development, but the mechanisms involved are unclear. Here we used single-cell RNA-sequencing to characterize the developmental path of 5-OP-RU-specific thymocytes. In addition to the known MAIT1 and MAIT17 effector subsets selected on bone-marrow-derived hematopoietic cells, we identified 5-OP-RU-specific thymocytes that were selected on thymic epithelial cells and differentiated into CD44- naive T cells. MAIT cell positive selection required signaling through the adapter, SAP, that controlled the expression of the transcription factor, ZBTB16. Pseudotemporal ordering of single cells revealed transcriptional trajectories of 5-OP-RU-specific thymocytes selected on either thymic epithelial cells or hematopoietic cells. The resulting model illustrates T cell lineage decisions.


Assuntos
Linhagem da Célula/imunologia , Células T Invariáveis Associadas à Mucosa/citologia , Células T Invariáveis Associadas à Mucosa/imunologia , Timócitos/citologia , Timócitos/imunologia , Animais , Sequência de Bases , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Receptores de Hialuronatos/metabolismo , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica/biossíntese , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Análise de Sequência de RNA , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo , Timo/citologia , Timo/imunologia
2.
Cancer Immunol Immunother ; 68(8): 1245-1261, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31222486

RESUMO

The efficacy of cancer immunotherapy, including treatment with immune-checkpoint inhibitors, often is limited by ineffective presentation of antigenic peptides that elicit T-cell-mediated anti-tumor cytotoxic responses. Manipulation of antigen presentation pathways is an emerging approach for enhancing the immunogenicity of tumors in immunotherapy settings. ER aminopeptidase 1 (ERAP1) is an intracellular enzyme that trims peptides as part of the system that generates peptides for binding to MHC class I molecules (MHC-I). We hypothesized that pharmacological inhibition of ERAP1 in cells could regulate the cellular immunopeptidome. To test this hypothesis, we treated A375 melanoma cells with a recently developed potent ERAP1 inhibitor and analyzed the presented MHC-I peptide repertoire by isolating MHC-I, eluting bound peptides, and identifying them using capillary chromatography and tandem mass spectrometry (LC-MS/MS). Although the inhibitor did not reduce cell-surface MHC-I expression, it induced qualitative and quantitative changes in the presented peptidomes. Specifically, inhibitor treatment altered presentation of about half of the total 3204 identified peptides, including about one third of the peptides predicted to bind tightly to MHC-I. Inhibitor treatment altered the length distribution of eluted peptides without change in the basic binding motifs. Surprisingly, inhibitor treatment enhanced the average predicted MHC-I binding affinity, by reducing presentation of sub-optimal long peptides and increasing presentation of many high-affinity 9-12mers, suggesting that baseline ERAP1 activity in this cell line is destructive for many potential epitopes. Our results suggest that chemical inhibition of ERAP1 may be a viable approach for manipulating the immunopeptidome of cancer.


Assuntos
Aminopeptidases/metabolismo , Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Vacinas Anticâncer/imunologia , Epitopos de Linfócito T/metabolismo , Imunoterapia/métodos , Melanoma/tratamento farmacológico , Antígenos de Histocompatibilidade Menor/metabolismo , Peptídeos/metabolismo , Inibidores de Proteases/farmacologia , Linfócitos T Citotóxicos/imunologia , Aminopeptidases/antagonistas & inibidores , Apresentação do Antígeno , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunogenicidade da Vacina , Ativação Linfocitária , Terapia de Alvo Molecular , Peptídeos/genética , Peptídeos/imunologia , Ligação Proteica
3.
Nat Commun ; 10(1): 2243, 2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113973

RESUMO

Mucosal-associated invariant T (MAIT) cells express an invariant TRAV1/TRAJ33 TCR-α chain and are restricted to the MHC-I-like molecule, MR1. Whether MAIT cell development depends on this invariant TCR-α chain is unclear. Here we generate Traj33-deficient mice and show that they are highly depleted of MAIT cells; however, a residual population remains and can respond to exogenous antigen in vitro or pulmonary Legionella challenge in vivo. These residual cells include some that express Trav1+ TCRs with conservative Traj-gene substitutions, and others that express Trav1- TCRs with a broad range of Traj genes. We further report that human TRAV1-2- MR1-restricted T cells contain both MAIT-like and non-MAIT-like cells, as judged by their TCR repertoire, antigen reactivity and phenotypic features. These include a MAIT-like population that expresses a public, canonical TRAV36+ TRBV28+ TCR. Our findings highlight the TCR diversity and the resulting potential impact on antigen recognition by MR1-restricted T cells.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Legionelose/imunologia , Antígenos de Histocompatibilidade Menor/metabolismo , Células T Invariáveis Associadas à Mucosa/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Animais , Apresentação do Antígeno/imunologia , Modelos Animais de Doenças , Células HEK293 , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Legionella/imunologia , Legionelose/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Antígenos de Histocompatibilidade Menor/imunologia , Células T Invariáveis Associadas à Mucosa/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia
4.
Nat Genet ; 51(6): 990-998, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31133746

RESUMO

The histone acetyl reader bromodomain-containing protein 4 (BRD4) is an important regulator of chromatin structure and transcription, yet factors modulating its activity have remained elusive. Here we describe two complementary screens for genetic and physical interactors of BRD4, which converge on the folate pathway enzyme MTHFD1 (methylenetetrahydrofolate dehydrogenase, cyclohydrolase and formyltetrahydrofolate synthetase 1). We show that a fraction of MTHFD1 resides in the nucleus, where it is recruited to distinct genomic loci by direct interaction with BRD4. Inhibition of either BRD4 or MTHFD1 results in similar changes in nuclear metabolite composition and gene expression; pharmacological inhibitors of the two pathways synergize to impair cancer cell viability in vitro and in vivo. Our finding that MTHFD1 and other metabolic enzymes are chromatin associated suggests a direct role for nuclear metabolism in the control of gene expression.


Assuntos
Ácido Fólico/metabolismo , Regulação da Expressão Gênica , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cromatina/genética , Técnicas de Inativação de Genes , Humanos , Mutação com Perda de Função , Ligação Proteica , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Transporte Proteico , Transdução de Sinais , Transcrição Genética
5.
Vet Res Commun ; 43(2): 115-122, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30989431

RESUMO

Dendritic cells (DC) are important antigen-presenting cells and are among the least characterized immune cells in the chicken. In order to obtain chicken DC, current protocols require isolation of bone marrow myeloid progenitor cells and induction of DC differentiation with supplemental cytokines or negative selection of splenic cell preparations. Chicken peritoneal exudate cells (PEC) have traditionally been a source of various immune cells for ex vivo studies, primarily to investigate heterophils and macrophages. In this study, we observe the presence of CD205+ PEC populations, a marker of DC, as an additional resource to isolate and study chicken primary DCs. A panel of monoclonal antibodies was developed against the chicken CD205 DC marker and used to isolate CD205+ DC from the PEC population using magnetic bead cell sorting. This study reports the development of new anti-CD205 monoclonal antibodies as a reagent for chicken DC research, as well as PEC as a potential source of CD205+ DC for ex vivo studies in the chicken.


Assuntos
Antígenos CD/metabolismo , Separação Celular/veterinária , Galinhas/imunologia , Células Dendríticas/citologia , Lectinas Tipo C/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Células Dendríticas/imunologia , Sefarose/imunologia
6.
Future Oncol ; 15(15): 1771-1780, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30997850

RESUMO

Aim: MTHFD1 was the enzyme providing one-carbon derivatives of tetrahydrofolate. We sought to investigate the impact of MTHFD1 on hepatocellular carcinoma (HCC). Methods: Bioinformatic analysis, western blot and immunohistochemistry were conducted to detect MTHFD1 expression in HCC. The relationships between MTHFD1 and prognosis of 172 HCCs were analyzed by Kaplan-Meier method and Cox proportional hazards model. Results: High MTHFD1 expression in HCC represented poor prognosis (overall survival p = 0.025; time to recurrence p = 0.044). Combining MTHFD1 with serum AFP, survival analysis demonstrated the prognosis of the MTHFD1 low expression and AFP ≤20 ng/ml group was better than that of the MTHFD1 high expression or AFP >20 ng/ml group and the MTHFD1 high expression and AFP >20 ng/ml group (overall survival p < 0.0001; time to recurrence p < 0.0001). Conclusion: High MTHFD1 expression in HCC indicated poorer prognosis. Combining MTHFD1 with serum AFP improved the accuracy of prognostic prediction.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/mortalidade , Expressão Gênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/mortalidade , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Antígenos de Histocompatibilidade Menor/genética , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor/metabolismo , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Prognóstico , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco , Carga Tumoral , alfa-Fetoproteínas/metabolismo
8.
EBioMedicine ; 41: 91-104, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30826357

RESUMO

BACKGROUND: The increased prevalence of cardiovascular disease (CVD) indicates a demand for novel therapeutic approaches. Proteome analysis of vascular tissues from animal models and humans with CVD could lead to the identification of novel druggable targets. METHODS: LC-MS/MS analysis of thoracic aortas from three mouse models of non-diabetic and diabetic (streptozotocin (STZ)-induced) atherosclerosis followed by bioinformatics/pathway analysis was performed. Selected findings were confirmed by proteomics analysis of human vessels from patients with CVD as well as in vitro studies (migration, proliferation, angiogenesis assays) using endothelial (HUVEC) cells. FINDINGS: Comparative tissue proteomics of low density lipoprotein receptor deficient (Ldlr-/-) and diabetic Ldlr-/- (Ldlr-/-STZ) with wild type (WT) animals led to the identification of 284 differentially expressed proteins in both models. Among them, 177 proteins were also differentially expressed in diabetic apolipoprotein E deficient (ApoE-/-STZ) mice, suggesting expression changes associated with atherosclerosis independent of the model used. These proteins recapitulated the hallmarks of atherosclerosis. Comparison of these findings with differentially expressed proteins in human vessels with CVD enabled shortlisting of six commonly dysregulated proteins. Among them, lysine-specific demethylase 5D (KDM5D) exhibited pronounced overexpression accompanied by a reduction in the protein levels of its substrate, the trimethylated lysine 4 of histone H3 (H3K4me3), in patients with CVD. Functional interference studies applying a KDM5 inhibitor on HUVEC reduced cell proliferation, migration and tube-forming ability in vitro. INTERPRETATION: This high-throughput proteomics strategy identified KDM5 histone demethylases being potentially involved in CVD, possibly by affecting H3K4 methylation. FUND: [SysVasc, HEALTH-2013 603288], [ERA-CVD PROACT: ANR-17-ECVD-0006, 01KL1805], [FRM, DEQ20170336759].


Assuntos
Aterosclerose/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Histona Desmetilases/genética , Antígenos de Histocompatibilidade Menor/genética , Animais , Aterosclerose/genética , Cardiomiopatias Diabéticas/genética , Histona Desmetilases/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Antígenos de Histocompatibilidade Menor/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteômica
9.
Genes Cells ; 24(5): 338-353, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30821042

RESUMO

Reassembly of the nuclear pore complex (NPC) at the end of mitosis is an important event for eukaryotic nuclear function. In this study, we examined the dynamic behaviors of the endoplasmic reticulum (ER) by "Live CLEM" imaging. In metaphase, numerous fenestrations on the ER membrane were observed around chromosomes. In telophase, these fenestrations became filled at the region attached to chromosomes, whereas they remained open at the region unattached to chromosomes, suggesting that NPC assembly takes place at fenestrations on the membrane. To determine the roles of nucleoporins in postmitotic NPC formation, we used artificial beads conjugated with anti-GFP antibody, which captures GFP-fused proteins on the beads when incorporated into cells. Live CLEM imaging of telophase cells containing Nup133-coated beads or Nup153-coated beads showed that Nup133 and Nup153, as the sole effector molecules, assembled the NPC-like structure on the membrane fenestrations. Indirect immunofluorescence staining of the Nup133-coated beads showed that Nup133 effectively assembled Nup107 and ELYS, whereas minimal assembly of Nup98 and Nup62 was observed; the Nup153-coated bead effectively assembled Nup98, Nup62 and Pom121, but assembled neither Nup107 nor ELYS. Our results suggest that Nup133 and Nup153 play different roles in assembling the NPC on membrane fenestrations.


Assuntos
Antígenos de Histocompatibilidade Menor/metabolismo , Mitose , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Poro Nuclear/metabolismo , Células HeLa , Humanos , Poro Nuclear/ultraestrutura , Ligação Proteica
10.
Hum Immunol ; 80(5): 302-309, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30817945

RESUMO

Autoimmune and autoinflammatory diseases affect millions worldwide. These classes of disease involve abnormal immune activation of both the innate and adaptive immune systems. While both classes of disease represent a spectrum of aberrant immune activation, excessive activation of the innate immune system has been considered causal for the inflammation and tissue damage found in autoinflammatory diseases, while excessive activation of the adaptive immune system has been thought to primarily contribute to end-organ symptoms noted in autoimmune diseases. Interestingly, the endoplasmic reticulum aminopeptidase 1 (ERAP1) protein, well known for its aminopeptidase function as a "molecular ruler", trimming peptides prior to their loading onto MHC-I molecules for antigen presentation in the ER, has also been shown to be genetically associated with both autoinflammatory and autoimmune diseases. Indeed, this multifaceted protein has been found to have many functions that affect both the innate and adaptive immune responses. In this review, we summarize these findings, with an attempt to identify the possible ERAP1 dependent mechanisms responsible for the pathogenesis of multiple, ERAP1 associated diseases.


Assuntos
Aminopeptidases/genética , Aminopeptidases/metabolismo , Doenças Autoimunes/etiologia , Doenças Autoimunes/metabolismo , Autoimunidade , Inflamação/etiologia , Inflamação/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Imunidade Adaptativa , Aminopeptidases/química , Animais , Apresentação do Antígeno/imunologia , Suscetibilidade a Doenças , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Imunidade Inata , Antígenos de Histocompatibilidade Menor/química
11.
Hum Immunol ; 80(5): 318-324, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30825518

RESUMO

The endoplasmic reticulum (ER) aminopeptidases ERAP1 and ERAP2 are two multifunctional enzymes playing an important role in the biological processes requiring trimming of substrates, including the generation of major histocompatibility complex (MHC) class I binding peptides. In the absence of ERAP enzymes, the cells exhibit a different pool of peptides on their surface which can promote both NK and CD8+ T cell-mediated immune responses. The expression of ERAP1 and ERAP2 is frequently altered in tumors, as compared to their normal counterparts, but how this affects tumor growth and anti-tumor immune responses has been little investigated. This review will provide an overview of current knowledge on transcriptional and post-transcriptional regulations of ERAP enzymes, and will discuss the contribution of recent studies to our understanding of ERAP1 and ERAP2 role in cancer immunity.


Assuntos
Aminopeptidases/genética , Aminopeptidases/metabolismo , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Animais , Apresentação do Antígeno/imunologia , Retículo Endoplasmático/metabolismo , Variação Genética , Genômica/métodos , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunoterapia , Neoplasias/imunologia , Neoplasias/terapia , Ligação Proteica , Transcrição Genética
12.
Hum Immunol ; 80(5): 296-301, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849449

RESUMO

ERAP1 is an aminopeptidase involved in trimming long peptides to the lengths required for presentation by MHC class I. ERAP1 substrate preference is for peptides with hydrophobic or aliphatic N-terminal amino acids, with lower efficacy with charged and small hydrophilic amino acids and almost complete inefficiency with proline. Since ERAP1 efficiently trims peptides to eight amino acids or even shorter, and many MHC-I allotypes can only bind peptides that are eight or nine amino acids or longer, ERAP1 both produces and destroys potential ligands of these alleles. The observation that ERAP1 modulates the levels of presentation for only a subset of the immunopeptidome conflicts with the common assumption that most MHC-I peptides are derived from longer peptides that are produced by the proteasome, transported into the endoplasmic reticulum (ER) by the Transporter Associated Peptide Presentation (TAP) and then trimmed by ERAP1. A more likely mechanism is that cellular protein degradation produces surplus amounts of peptides that fit perfectly and are rapidly loaded onto the MHC, with only a minority of peptides requiring trimming within the ER before loading. Alternatively, ERAP1 may not be present in all ER compartments or vesicles where peptide processing and loading take place and thus affects just a subset of the immunopeptidome.


Assuntos
Aminopeptidases/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Peptídeos/imunologia , Peptídeos/metabolismo , Alelos , Aminopeptidases/genética , Animais , Apresentação do Antígeno , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Autoimunidade , Ativação Enzimática , Haplótipos , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Ligantes , Antígenos de Histocompatibilidade Menor/genética , Ligação Proteica , Proteólise , Relação Estrutura-Atividade
13.
Hum Immunol ; 80(5): 339-343, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30794838

RESUMO

The objective of this case-control study was to evaluate the role of four single-nucleotide polymorphisms in the ERAP1 (rs2287987, rs30187, rs27044) and ERAP2 (rs2248374) genes and their haplotypes in predicting the risk for ankylosing spondylitis (AS) on a well-defined Polish population. Our study confirmed the strong association between the HLA-B*27 allele and the disease. For all tested ERAP1 SNPs we found significant differences in the minor allele and genotype distribution between patients and controls. The strongest association with AS was observed for rs30187. The minor T allele and homozygous TT genotype of this SNP significantly increased disease risk (OR = 1.56, 95%CI = 1.22-1.99, p = 0.0004 and OR = 2.52, 95%CI = 1.50-4.25, p = 0.001, respectively). In the case of rs2287987, minor C allele exerted a protective effect (OR = 0.64, 95%CI = 0.46-0.88, p = 0.008). In contrast to ERAP1, we observed no effect of rs2248374 in ERAP2 on the disease. We also carried out ERAP1-ERAP2 haplotype analysis to demonstrate a possible association of both genes with AS. Results showed that the haplotype H4, containing ERAP1 SNPs associated with high enzymatic activity, together with the presence of ERAP2 expression, significantly increased the risk of AS (OR = 1.97, 95% CI = 1.21-3.21, pcorr = 0.048). By contrast, the haplotype H5 coding for low activity of ERAP1 and the lack of ERAP2 expression was strongly protective (OR = 0.41, 95% CI = 0.23-0.72, pcorr = 0.008).


Assuntos
Aminopeptidases/genética , Predisposição Genética para Doença , Haplótipos , Antígenos de Histocompatibilidade Menor/genética , Espondilite Anquilosante/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aminopeptidases/metabolismo , Biomarcadores , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Antígeno HLA-B27/genética , Antígeno HLA-B27/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor/metabolismo , Razão de Chances , Polônia , Polimorfismo de Nucleotídeo Único , Espondilite Anquilosante/diagnóstico , Espondilite Anquilosante/epidemiologia , Adulto Jovem
14.
Hum Immunol ; 80(5): 325-334, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30797823

RESUMO

The endoplasmic reticulum aminopeptidases (ERAPs), ERAP1 and ERAP2, makes a role in shaping the HLA class I peptidome by trimming peptides to the optimal size in MHC-class I-mediated antigen presentation and educating the immune system to differentiate between self-derived and foreign antigens. Association studies have shown that genetic variations in ERAP1 and ERAP2 genes increase susceptibility to autoimmune diseases, infectious diseases, and cancers. Both ERAP1 and ERAP2 genes exhibit diverse polymorphisms in different populations, which may influence their susceptibly to the aforementioned diseases. In this article, we review the distribution of ERAP1 and ERAP2 gene polymorphisms in various populations; discuss the risk or protective influence of these gene polymorphisms in autoimmune diseases, infectious diseases, and cancers; and highlight how ERAP genetic variations can influence disease associations.


Assuntos
Aminopeptidases/genética , Predisposição Genética para Doença , Antígenos de Histocompatibilidade Menor/genética , Polimorfismo de Nucleotídeo Único , Aminopeptidases/química , Aminopeptidases/metabolismo , Apresentação do Antígeno/imunologia , Doenças Autoimunes/etiologia , Doenças Autoimunes/metabolismo , Grupos de Populações Continentais/genética , Evolução Molecular , Genética Populacional , Genótipo , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/metabolismo , Relação Estrutura-Atividade
15.
Nat Commun ; 10(1): 603, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30723194

RESUMO

Zinc ions (Zn2+) are imported into the early secretory pathway by Golgi-resident transporters, but their handling and functions are not fully understood. Here, we show that Zn2+ binds with high affinity to the pH-sensitive chaperone ERp44, modulating its localization and ability to retrieve clients like Ero1α and ERAP1 to the endoplasmic reticulum (ER). Silencing the Zn2+ transporters that uptake Zn2+ into the Golgi led to ERp44 dysfunction and increased secretion of Ero1α and ERAP1. High-resolution crystal structures of Zn2+-bound ERp44 reveal that Zn2+ binds to a conserved histidine-cluster. The consequent large displacements of the regulatory C-terminal tail expose the substrate-binding surface and RDEL motif, ensuring client capture and retrieval. ERp44 also forms Zn2+-bridged homodimers, which dissociate upon client binding. Histidine mutations in the Zn2+-binding sites compromise ERp44 activity and localization. Our findings reveal a role of Zn2+ as a key regulator of protein quality control at the ER-Golgi interface.


Assuntos
Proteínas de Membrana/metabolismo , Chaperonas Moleculares/metabolismo , Via Secretória , Zinco/metabolismo , Aminopeptidases/metabolismo , Sítios de Ligação/genética , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Cristalografia por Raios X , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Células HeLa , Células Hep G2 , Humanos , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Oxirredutases/metabolismo , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Controle de Qualidade , Interferência de RNA , Zinco/química
16.
Pathog Dis ; 77(1)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30753412

RESUMO

Macrophages are the primary host target cells of Mycobacterium tuberculosis (M. tb). As a subunit of immunoregulatory cytokines IL-27 and IL-35, Epstein-Barr virus-induced gene 3 (EBI3) has typically been explored as the secreted form and assessed in terms of its effects triggered by extracellular EBI3. However, little is known about intracellular EBI3 function. In the current study, we report that EBI3 production by macrophages is elevated in TB patients. We further demonstrate that increased EBI3 accumulates in virulent M. tb-treated murine macrophages. Eukaryotic translation elongation factor 1-alpha 1 (eEF1A1) binds to intracellular EBI3 to reduce Lys48 (K48)-linked ubiquitination of EBI3, leading to EBI3 accumulation. Moreover, the intracellular EBI3 inhibits caspase-3-mediated apoptosis in M. tb-treated macrophages. Herein, we propose a novel mechanism for accumulating intracellular EBI3 and its regulation of macrophage apoptosis in response to virulent M. tb.


Assuntos
Apoptose/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Mycobacterium tuberculosis/imunologia , Receptores de Citocinas/metabolismo , Tuberculose/imunologia , Tuberculose/metabolismo , Animais , Estudos de Casos e Controles , Caspase 3/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno/imunologia , Humanos , Contagem de Leucócitos , Camundongos , Camundongos Knockout , Fator 1 de Elongação de Peptídeos/metabolismo , Ligação Proteica , RNA Interferente Pequeno/genética , Tuberculose/microbiologia
17.
Intern Med ; 58(9): 1199-1207, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30626832

RESUMO

Patients with Behçet's disease (BD) suffer from episodic ocular and mucocutaneous attacks, resulting in a reduced quality of life. The phenotype of Japanese BD has been changing over the past 20 years, and the rate of human leukocyte antigen (HLA)-B*51-positive complete type is decreasing while that of intestinal type is increasing. This phenotypical evolution may be related to changes in as-yet-unknown environmental factors, as the immigration influx in Japan is low. Mechanisms discovered by genome-wide association studies include ERAP1-mediated HLA class I antigen bounding pathway, autoinflammation, Th17 cells, natural killer cells, and polarized macrophages, a similar genetic architecture to Crohn's disease, ankylosing spondylitis, and psoriasis. As for treatments, management guidelines have been implemented, and the development of tumor necrosis factor (TNF) inhibitors is markedly improving the outcome of BD, but evidence supporting treatment for special-type BD is limited. The classification of BD into distinct clusters based on clinical manifestations and genetic factors is crucial to the development of optimized medicine.


Assuntos
Síndrome de Behçet/genética , Aminopeptidases/metabolismo , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/tratamento farmacológico , Síndrome de Behçet/epidemiologia , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Imunossupressores/uso terapêutico , Japão/epidemiologia , Células Matadoras Naturais/imunologia , Antígenos de Histocompatibilidade Menor/metabolismo , Fenótipo , Qualidade de Vida , Fatores de Risco , Fator de Necrose Tumoral alfa/antagonistas & inibidores
18.
Virology ; 529: 65-72, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30665099

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) infects monocyte-derived DCs, and previous reports have shown that PRRSV does not infect conventional DCs (cDCs) in vitro, but the effects on cDCs from lymphoid tissues are unknown. This study analyzed the response and susceptibility of tonsil DEC205+cDCs from infected pigs. We confirmed the phenotype and lineage of bona fide tonsil cDCs with the mRNA expression of FLT3+ and the phenotype MHCII+CADM1highDEC205+ (DEC205+cDCs). These cells were not infected by PRRSV, whereas CD163+ tonsil cells were infected. The numbers of tonsil cDCs and CD163+ cells were not affected by PRRSV, in contrast to the reduction in alveolar macrophage numbers. DEC205+cDCs exhibited an increase in the expression of IL-12 at 5 days postinfection, suggesting a proinflammatory response by these cells to the virus. In summary, this study confirms that, in vitro and in vivo, cDCs are not susceptible to PRRSV but can respond against it.


Assuntos
Células Dendríticas/virologia , Tonsila Palatina/citologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Molécula 1 de Adesão Celular/genética , Molécula 1 de Adesão Celular/metabolismo , Regulação da Expressão Gênica/imunologia , Interleucina-12/genética , Interleucina-12/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Complexo Principal de Histocompatibilidade , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Síndrome Respiratória e Reprodutiva Suína/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Suínos , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
19.
Phytomedicine ; 57: 117-128, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30668314

RESUMO

BACKGROUND: Topotecan (TPT) is a Topo I inhibitor and shows obvious anti-cancer effects on gastric cancer. Cancer cells reprogram their metabolic pathways to increase nutrients uptake, which has already been a hallmark of cancer. But the effect of TPT on metabolism in gastric cancer remains unknown. PURPOSE: To investigate the effect of TPT on metabolism in gastric cancer. METHODS: ATP production was measured by ATP Assay kit. Glucose and glutamine uptake were measured by Glucose (HK) Assay Kit and Glutamine/Glutamate Determination Kit respectively. To detect glutathione (GSH) concentration and reactive oxygen species (ROS) generation, GSH and GSSG Assay Kit and ROS Assay Kit were adopted. Apoptosis rates, mitochondrial membrane potential (MMP) were determined by flow cytometry and protein levels were analyzed by immumohistochemical staining and western blotting. RESULTS: TPT increased ATP production. TPT promoted glucose uptake possibly via up-regulation of hexokinase 2 (HK2) or glucose transporter 1 (GLUT1) expression, while decreased glutamine uptake by down-regulation of ASCT2 expression. ASCT2 inhibitor GPNA and ASCT2 knockdown significantly suppressed the growth of gastric cancer cells. Inhibition of ASCT2 reduced glutamine uptake which led to decreased production of GSH and increased ROS level. ASCT2 knockdown induced apoptosis via the mitochondrial pathway and weakened anti-cancer effect of TPT. CONCLUSION: TPT inhibits glutamine uptake via down-regulation of ASCT2 which causes oxidative stress and induces apoptosis through the mitochondrial pathway. Moreover, TPT inhibits proliferation partially via ASCT2. These observations reveal a previously undescribed mechanism of ASCT2 regulated gastric cancer proliferation and demonstrate ASCT2 is a potential anti-cancer target of TPT.


Assuntos
Sistema ASC de Transporte de Aminoácidos/metabolismo , Antineoplásicos/farmacologia , Antígenos de Histocompatibilidade Menor/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Topotecan/farmacologia , Sistema ASC de Transporte de Aminoácidos/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica , Glutamina/metabolismo , Glutationa/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Antígenos de Histocompatibilidade Menor/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular/métodos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
20.
Immunology ; 157(1): 13-20, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30681737

RESUMO

Interleukin-35 (IL-35) is a recently identified heterodimeric cytokine in the IL-12 family. It consists of an IL-12 subunit α chain (P35) and IL-27 subunit Epstein-Barr virus-induced gene 3 (EBI3) ß chain. Unlike the other IL-12 family members, it signals through four unconventional receptors: IL-12Rß2-IL-27Rα, IL-12Rß2-IL-12Rß2, IL-12Rß2-GP130, and GP130-GP130. Interleukin-35 signaling is mainly carried out through the signal transducer and activator of transcription family of proteins. It is secreted not only by regulatory T (Treg) cells, but also by CD8+ Treg cells, activated dendritic cells and regulatory B cells. It exhibits immunosuppressive functions distinct from those of other members of the IL-12 family; these are mediated primarily by the inhibition of T helper type 17 cell differentiation and promotion of Treg cell proliferation. Interleukin-35 plays a critical role in several immune-associated diseases, such as autoimmune diseases and viral and bacterial infections, as well as in tumors. In this review, we summarize the structure and function of IL-35, describe its role in immune-related disorders, and discuss the mechanisms by which it regulates the development and progression of diseases, including inflammatory bowel disease, collagen-induced arthritis, allergic airway disease, hepatitis, and tumors. The recent research on IL-35, combined with improved techniques of studying receptors and signal transduction pathways, allows for consideration of IL-35 as a novel immunotherapy target.


Assuntos
Doenças do Sistema Imunitário/metabolismo , Imunoterapia/métodos , Subunidade p35 da Interleucina-12/metabolismo , Interleucinas/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Autoimunidade , Humanos , Subunidade p35 da Interleucina-12/genética , Interleucinas/genética , Ativação Linfocitária , Antígenos de Histocompatibilidade Menor/genética , Transdução de Sinais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA