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1.
Cancer Res ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635899

RESUMO

T cell exhaustion is a major contributor to immunosuppression in the tumor microenvironment (TME). Blockade of key regulators of T cell exhaustion, such as PD-1, can reinvigorate tumor-specific T cells and activate anti-tumor immunity in various types of cancer. Here, we identified that CD106 was specifically expressed in exhausted CD8+ T cells in the TME using single-cell RNA-sequencing. High CD106 expression in the TME in clinical samples corresponded to improved response to cancer immunotherapy. CD106 in tumor-specific T cells suppressed anti-tumor immunity both in vitro and in vivo, and loss of CD106 in CD8+ T cells suppressed tumor growth and improved response to PD-1 blockade. Mechanistically, CD106 inhibited T-cell receptor (TCR) signaling by interacting with the TCR/CD3 complex and reducing its surface expression. Together, these findings provide insights into the immunosuppressive role of CD106 expressed in tumor-specific exhausted CD8+ T cells, identifying it as a potential biomarker and therapeutic target for cancer immunotherapy.

2.
JCI Insight ; 9(3)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329122

RESUMO

Immune checkpoint inhibitors (ICIs) are indicated for a diverse range of cancer types, and characterizing the tumor immune microenvironment is critical for optimizing therapeutic strategies, including ICIs. T cell infiltration and activation status in the tumor microenvironment greatly affects the efficacy of ICIs. Here, we show that semaphorin 6D (Sema6D) forward signaling, which is reportedly involved in coordinating the orientation of cell development and migration as a guidance factor, impaired the infiltration and activation of tumor-specific CD8+ T cells in murine oral tumors. Sema6D expressed by nonhematopoietic cells was responsible for this phenotype. Plexin-A4, a receptor for Sema6D, inhibited T cell infiltration and partially suppressed CD8+ T cell activation and proliferation induced by Sema6D stimulation. Moreover, mouse oral tumors, which are resistant to PD-1-blocking treatment in wild-type mice, showed a response to the treatment in Sema6d-KO mice. Finally, analyses of public data sets of human head and neck squamous cell carcinoma, pan-cancer cohorts, and a retrospective cohort study showed that SEMA6D was mainly expressed by nonhematopoietic cells such as cancer cells, and SEMA6D expression was significantly negatively correlated with CD8A, PDCD1, IFNG, and GZMB expression. Thus, targeting Sema6D forward signaling is a promising option for increasing ICI efficacy.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Humanos , Camundongos , Proliferação de Células , Neoplasias de Cabeça e Pescoço/genética , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Microambiente Tumoral
3.
Cell Rep ; 43(2): 113797, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38363680

RESUMO

Immune checkpoint inhibitors exert clinical efficacy against various types of cancer through reinvigoration of exhausted CD8+ T cells that attack cancer cells directly in the tumor microenvironment (TME). Using single-cell sequencing and mouse models, we show that CXCL13, highly expressed in tumor-infiltrating exhausted CD8+ T cells, induces CD4+ follicular helper T (TFH) cell infiltration, contributing to anti-tumor immunity. Furthermore, a part of the TFH cells in the TME exhibits cytotoxicity and directly attacks major histocompatibility complex-II-expressing tumors. TFH-like cytotoxic CD4+ T cells have high LAG-3/BLIMP1 and low TCF1 expression without self-renewal ability, whereas non-cytotoxic TFH cells express low LAG-3/BLIMP1 and high TCF1 with self-renewal ability, closely resembling the relationship between terminally differentiated and stem-like progenitor exhaustion in CD8+ T cells, respectively. Our findings provide deep insights into TFH-like CD4+ T cell exhaustion with helper progenitor and cytotoxic differentiated functions, mediating anti-tumor immunity orchestrally with CD8+ T cells.


Assuntos
Exaustão das Células T , Microambiente Tumoral , Animais , Camundongos , Linfócitos T CD8-Positivos , Diferenciação Celular , Linfócitos T CD4-Positivos
4.
Sci Adv ; 9(24): eadf0661, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37315144

RESUMO

Severe acute respiratory syndrome coronavirus 2-neutralizing antibodies primarily target the spike receptor binding domain (RBD). However, B cell antigen receptors (BCRs) on RBD-binding memory B (Bmem) cells have variation in the neutralizing activities. Here, by combining single Bmem cell profiling with antibody functional assessment, we dissected the phenotype of Bmem cell harboring the potently neutralizing antibodies in coronavirus disease 2019 (COVID-19)-convalescent individuals. The neutralizing subset was marked by an elevated CD62L expression and characterized by distinct epitope preference and usage of convergent VH (variable region of immunoglobulin heavy chain) genes, accounting for the neutralizing activities. Concordantly, the correlation was observed between neutralizing antibody titers in blood and CD62L+ subset, despite the equivalent RBD binding of CD62L+ and CD62L- subset. Furthermore, the kinetics of CD62L+ subset differed between the patients who recovered from different COVID-19 severities. Our Bmem cell profiling reveals the unique phenotype of Bmem cell subset that harbors potently neutralizing BCRs, advancing our understanding of humoral protection.


Assuntos
Subpopulações de Linfócitos B , COVID-19 , Selectina L , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , SARS-CoV-2
5.
Sci Adv ; 9(20): eade0718, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37205755

RESUMO

Immune checkpoint inhibitors (ICIs) have caused revolutionary changes in cancer treatment, but low response rates remain a challenge. Semaphorin 4A (Sema4A) modulates the immune system through multiple mechanisms in mice, although the role of human Sema4A in the tumor microenvironment remains unclear. This study demonstrates that histologically Sema4A-positive non-small cell lung cancer (NSCLC) responded significantly better to anti-programmed cell death 1 (PD-1) antibody than Sema4A-negative NSCLC. Intriguingly, SEMA4A expression in human NSCLC was mainly derived from tumor cells and was associated with T cell activation. Sema4A promoted cytotoxicity and proliferation of tumor-specific CD8+ T cells without terminal exhaustion by enhancing mammalian target of rapamycin complex 1 and polyamine synthesis, which led to improved efficacy of PD-1 inhibitors in murine models. Improved T cell activation by recombinant Sema4A was also confirmed using isolated tumor-infiltrating T cells from patients with cancer. Thus, Sema4A might be a promising therapeutic target and biomarker for predicting and promoting ICI efficacy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Semaforinas , Animais , Humanos , Camundongos , Anticorpos Bloqueadores , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linfócitos T CD8-Positivos , Proliferação de Células , Neoplasias Pulmonares/tratamento farmacológico , Receptor de Morte Celular Programada 1 , Semaforinas/genética , Semaforinas/metabolismo , Microambiente Tumoral
6.
Cell Rep ; 38(5): 110331, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35108529

RESUMO

PD-1 blockade exerts clinical efficacy against various types of cancer by reinvigorating T cells that directly attack tumor cells (tumor-specific T cells) in the tumor microenvironment (TME), and tumor-infiltrating lymphocytes (TILs) also comprise nonspecific bystander T cells. Here, using single-cell sequencing, we show that TILs include skewed T cell clonotypes, which are characterized by exhaustion (Tex) or nonexhaustion signatures (Tnon-ex). Among skewed clonotypes, those in the Tex, but not those in the Tnon-ex, cluster respond to autologous tumor cell lines. After PD-1 blockade, non-preexisting tumor-specific clonotypes in the Tex cluster appear in the TME. Tumor-draining lymph nodes (TDLNs) without metastasis harbor a considerable number of such clonotypes, whereas these clonotypes are rarely detected in peripheral blood. We propose that tumor-infiltrating skewed T cell clonotypes with an exhausted phenotype directly attack tumor cells and that PD-1 blockade can promote infiltration of such Tex clonotypes, mainly from TDLNs.


Assuntos
Linfócitos T CD8-Positivos/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Microambiente Tumoral/imunologia , Animais , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Camundongos , Receptor de Morte Celular Programada 1/metabolismo , Microambiente Tumoral/efeitos dos fármacos
7.
Cancer Res Commun ; 2(7): 739-753, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36923281

RESUMO

Some patients experience mixed response to immunotherapy, whose biological mechanisms and clinical impact have been obscure. We obtained two tumor samples from lymph node (LN) metastatic lesions in a same patient. Whole exome sequencing for the both tumors and single-cell sequencing for the both tumor-infiltrating lymphocytes (TIL) demonstrated a significant difference in tumor clonality and TILs' characteristics, especially exhausted T-cell clonotypes, although a close relationship between the tumor cell and T-cell clones were observed as a response of an overlapped exhausted T-cell clone to an overlapped neoantigen. To mimic the clinical setting, we generated a mouse model of several clones from a same tumor cell line. Similarly, differential tumor clones harbored distinct TILs, and one responded to programmed cell death protein 1 (PD-1) blockade but the other did not in this model. We further conducted cohort study (n = 503) treated with PD-1 blockade monotherapies to investigate the outcome of mixed response. Patients with mixed responses to PD-1 blockade had a poor prognosis in our cohort. Particularly, there were significant differences in both tumor and T-cell clones between the primary and LN lesions in a patient who experienced tumor response to anti-PD-1 mAb followed by disease progression in only LN metastasis. Our results underscore that intertumoral heterogeneity alters characteristics of TILs even in the same patient, leading to mixed response to immunotherapy and significant difference in the outcome. Significance: Several patients experience mixed responses to immunotherapies, but the biological mechanisms and clinical significance remain unclear. Our results from clinical and mouse studies underscore that intertumoral heterogeneity alters characteristics of TILs even in the same patient, leading to mixed response to immunotherapy and significant difference in the outcome.


Assuntos
Neoplasias , Animais , Camundongos , Estudos de Coortes , Neoplasias/genética , Imunoterapia/métodos , Linfócitos T , Linfócitos do Interstício Tumoral
8.
Gastroenterology ; 162(3): 799-812, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34687740

RESUMO

BACKGROUND & AIMS: A detailed understanding of antitumor immunity is essential for optimal cancer immune therapy. Although defective mutations in the B2M and HLA-ABC genes, which encode molecules essential for antigen presentation, have been reported in several studies, the effects of these defects on tumor immunity have not been quantitatively evaluated. METHODS: Mutations in HLA-ABC genes were analyzed in 114 microsatellite instability-high colorectal cancers using a long-read sequencer. The data were further analyzed in combination with whole-exome sequencing, transcriptome sequencing, DNA methylation array, and immunohistochemistry data. RESULTS: We detected 101 truncating mutations in 57 tumors (50%) and loss of 61 alleles in 21 tumors (18%). Based on the integrated analysis that enabled the immunologic subclassification of microsatellite instability-high colorectal cancers, we identified a subtype of tumors in which lymphocyte infiltration was reduced, partly due to reduced expression of HLA-ABC genes in the absence of apparent genetic alterations. Survival time of patients with such tumors was shorter than in patients with other tumor types. Paradoxically, tumor mutation burden was highest in the subtype, suggesting that the immunogenic effect of accumulating mutations was counterbalanced by mutations that weakened immunoreactivity. Various genetic and epigenetic alterations, including frameshift mutations in RFX5 and promoter methylation of PSMB8 and HLA-A, converged on reduced expression of HLA-ABC genes. CONCLUSIONS: Our detailed immunogenomic analysis provides information that will facilitate the improvement and development of cancer immunotherapy.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Genes MHC Classe I/genética , Evasão Tumoral/genética , Evasão Tumoral/imunologia , Microglobulina beta-2/genética , Alelos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Metilação de DNA , Epigênese Genética , Expressão Gênica , Antígenos HLA-A/genética , Antígenos HLA-A/metabolismo , Humanos , Imunogenética , Linfócitos do Interstício Tumoral , Instabilidade de Microssatélites , Complexo de Endopeptidases do Proteassoma/genética , Fatores de Transcrição de Fator Regulador X/genética , Taxa de Sobrevida , Microglobulina beta-2/metabolismo
9.
J Exp Med ; 218(1)2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33045065

RESUMO

A still unanswered question is what drives the small fraction of activated germinal center (GC) B cells to become long-lived quiescent memory B cells. We found here that a small population of GC-derived CD38intBcl6hi/intEfnb1+ cells with lower mTORC1 activity favored the memory B cell fate. Constitutively high mTORC1 activity led to defects in formation of the CD38intBcl6hi/intEfnb1+ cells; conversely, decreasing mTORC1 activity resulted in relative enrichment of this memory-prone population over the recycling-prone one. Furthermore, the CD38intBcl6hi/intEfnb1+ cells had higher levels of Bcl2 and surface BCR that, in turn, contributed to their survival and development. We also found that downregulation of Bcl6 resulted in increased expression of both Bcl2 and BCR. Given the positive correlation between the strength of T cell help and mTORC1 activity, our data suggest a model in which weak help from T cells together with provision of an increased survival signal are key for GC B cells to adopt a memory B cell fate.


Assuntos
Linfócitos B/imunologia , Reprogramação Celular/imunologia , Centro Germinativo/imunologia , Memória Imunológica , Transdução de Sinais/imunologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/imunologia , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Reprogramação Celular/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/imunologia , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Transdução de Sinais/genética , Linfócitos T Auxiliares-Indutores/imunologia
10.
J Environ Manage ; 231: 749-756, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30408768

RESUMO

Crushed stone powder and aluminum ash are industrial wastes, and effective utilization of these wastes has been highly expected. Since the main components of the two wastes are Si, Al and O, those wastes can be used as starting materials for synthesis of zeolites of which some types have been commercialized as catalysts and ion-exchangers. In this study, zeolites A and X well-known as practical materials were successfully synthesized with high purity using the two industrial wastes by a mild process based on two hydrothermal treatments with intermediate acid treatment. In the first hydrothermal treatment at 150 °C, quartz in the crushed stone powder was dissolved and acid-soluble hydroxysodalite (Na8(AlSiO4)6(H2O)2(OH)2) with Si/Al = 1 and sodium aluminosilicate (Na6(AlSiO4)6) were formed. Those compounds were dissolved with HCl aq. solution. The zeolites were successfully synthesized from the second hydrothermal treatment of the yellow dried filtrates at 80 °C in NaOH aq. solution. In the process proposed, removal of Ca from the crushed stone powder was effective to formation of zeolites A and/or X. Selective synthesis of zeolites A and X was achieved by controlling the acid treatment conditions. Furthermore, the effect of the drying condition of the filtrate obtained after the acid treatment was also investigated on the differences in the product phase.


Assuntos
Zeolitas , Alumínio , Catálise , Cinza de Carvão , Resíduos Industriais
11.
J Allergy Clin Immunol ; 143(3): 1163-1175.e15, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30053529

RESUMO

BACKGROUND: Chronic rhinosinusitis with nasal polyposis (CRSwNP) is characterized by eosinophilic inflammation and polyposis at the nose and paranasal sinus and a high concentration of IgE in nasal polyps (NPs). The causative antigen and pathogenesis of CRSwNP remain unknown. OBJECTIVE: We aimed to identify reactive allergens of IgE antibodies produced locally in NPs of patients with CRSwNP. We also attempted to unravel the differentiation pathway of IgE-producing B cells in NPs. METHODS: IgE reactivity of patients with CRSwNP was investigated by characterizing single cell-derived mAbs. T-cell response against identified allergens was investigated in vitro. NP-infiltrating lymphocytes were characterized by using flow cytometry. Immunoglobulins expressed in NPs were analyzed by using high-throughput DNA sequencing for immunoglobulin. RESULTS: About 20% of isolated IgE antibodies derived from NP-residing plasmablasts specifically recognized surface determinants of nasal bacteria, such as Staphylococcus aureus, Streptococcus pyogenes, and Haemophilus influenzae. A TH2 response against S pyogenes was observed in patients with CRSwNP. Flow cytometric analysis revealed sizable germinal center B-like cell and plasmablast subsets expressing IgE on the cell surface in NPs. High-throughput DNA sequencing immunoglobulin analysis highlighted the clonal connectivity of IgE with IgG and IgA1. The Iε-Cα1 circle transcript was detected in NPs. CONCLUSIONS: In patients with CRSwNP, nasal bacteria-reactive B cells differentiate into IgE-producing B cells through IgG/IgA1-IgE class switching, suggesting that allergic conversion of the mucosal response against nasal bacteria underlies disease pathogenesis.


Assuntos
Linfócitos B/imunologia , Bactérias/imunologia , Imunidade nas Mucosas , Imunoglobulina E/imunologia , Pólipos Nasais/imunologia , Rinite/imunologia , Sinusite/imunologia , Adulto , Idoso , Anticorpos Monoclonais/farmacologia , Células Cultivadas , Doença Crônica , Eosinofilia/imunologia , Eosinofilia/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/imunologia , Mucosa Nasal/microbiologia , Pólipos Nasais/microbiologia , Rinite/microbiologia , Sinusite/microbiologia , Adulto Jovem
12.
Immunity ; 48(4): 702-715.e4, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29669250

RESUMO

Higher- or lower-affinity germinal center (GC) B cells are directed either to plasma cell or GC recycling, respectively; however, how commitment to the plasma cell fate takes place is unclear. We found that a population of light zone (LZ) GC cells, Bcl6loCD69hi expressing a transcription factor IRF4 and higher-affinity B cell receptors (BCRs) or Bcl6hiCD69hi with lower-affinity BCRs, favored the plasma cell or recycling GC cell fate, respectively. Mechanistically, CD40 acted as a dose-dependent regulator for Bcl6loCD69hi cell formation. Furthermore, we found that expression of intercellular adhesion molecule 1 (ICAM-1) and signaling lymphocytic activation molecule (SLAM) in Bcl6loCD69hi cells was higher than in Bcl6hiCD69hi cells, thereby affording more stable T follicular helper (Tfh)-GC B cell contacts. These data support a model whereby commitment to the plasma cell begins in the GC and suggest that stability of Tfh-GC B cell contacts is key for plasma cell-prone GC cell formation.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos B/citologia , Antígenos CD40/metabolismo , Centro Germinativo/imunologia , Lectinas Tipo C/metabolismo , Plasmócitos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-6/metabolismo , Linfócitos T Auxiliares-Indutores/citologia , Animais , Linfócitos B/imunologia , Diferenciação Celular/imunologia , Molécula 1 de Adesão Intercelular/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Família de Moléculas de Sinalização da Ativação Linfocitária/biossíntese , Linfócitos T Auxiliares-Indutores/imunologia
13.
Proc Natl Acad Sci U S A ; 114(50): E10782-E10791, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29187532

RESUMO

Signal peptide peptidase (SPP) is an intramembrane aspartic protease involved in the maturation of the core protein of hepatitis C virus (HCV). The processing of HCV core protein by SPP has been reported to be critical for the propagation and pathogenesis of HCV. Here we examined the inhibitory activity of inhibitors for γ-secretase, another intramembrane cleaving protease, against SPP, and our findings revealed that the dibenzoazepine-type structure in the γ-secretase inhibitors is critical for the inhibition of SPP. The spatial distribution showed that the γ-secretase inhibitor compound YO-01027 with the dibenzoazepine structure exhibits potent inhibiting activity against SPP in vitro and in vivo through the interaction of Val223 in SPP. Treatment with this SPP inhibitor suppressed the maturation of core proteins of all HCV genotypes without the emergence of drug-resistant viruses, in contrast to the treatment with direct-acting antivirals. YO-01027 also efficiently inhibited the propagation of protozoa such as Plasmodium falciparum and Toxoplasma gondii These data suggest that SPP is an ideal target for the development of therapeutics not only against chronic hepatitis C but also against protozoiasis.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Antiprotozoários/farmacologia , Antivirais/farmacologia , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Dibenzazepinas/farmacologia , Hepacivirus/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Animais , Antiprotozoários/química , Antivirais/química , Linhagem Celular , Dibenzazepinas/química , Células HEK293 , Hepacivirus/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Plasmodium falciparum/efeitos dos fármacos , Inibidores de Proteases/química , Relação Estrutura-Atividade , Toxoplasma/efeitos dos fármacos , Proteínas do Core Viral/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos
14.
Sci Rep ; 7(1): 16428, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-29180749

RESUMO

The evolutional process of disease-associated autoantibodies in systemic lupus erythematosus (SLE) remains to be established. Here we show intraclonal diversification and affinity maturation of anti-nuclear antibody (ANA)-producing B cells in SLE. We identified a panel of monoclonal ANAs recognizing nuclear antigens, such as double-stranded DNA (dsDNA) and ribonucleoproteins (RNPs) from acute SLE subjects. These ANAs had relatively few, but nonetheless critical mutations. High-throughput immunoglobulin sequencing of blood lymphocytes disclosed the existence of sizable ANA lineages shearing critical mutations intraclonally. We further focused on anti-DNA antibodies, which are capable to bind to both single-stranded (ss) and dsDNA at high affinity. Crystal structure and biochemical analysis confirmed a direct role of the mutations in the acquisition of DNA reactivity and also revealed that these anti-DNA antibodies recognized an unpaired region within DNA duplex. Our study unveils the unique properties of high-affinity anti-DNA antibodies that are generated through antigen-driven affinity maturation in acute phase of SLE.


Assuntos
Anticorpos Antinucleares/imunologia , Antígenos/imunologia , Evolução Clonal/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Doença Aguda , Sequência de Aminoácidos , Anticorpos Antinucleares/química , Antígenos/química , Autoanticorpos/sangue , DNA/imunologia , Células HEK293 , Humanos , Lúpus Eritematoso Sistêmico/sangue , Mutação/genética , Taxa de Mutação , Filogenia , Sindecana-1/metabolismo
15.
J Exp Med ; 213(4): 605-19, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27022145

RESUMO

Balance in signal transducer and activator of transcription (STAT) activation is a key factor in regulating the fate of naive CD4(+)T cells. Here, we demonstrate that AT-rich interactive domain-containing protein 5a (Arid5a) in T cells directs naive CD4(+)T cells to differentiate into inflammatory CD4(+)T cells, especially Th17 cells, through selective stabilization of Stat3(but not Stat1 and Stat5) mRNA in an IL-6-dependent manner. Loss of Arid5a in T cells led to reduction of STAT3 level under Th17-polarizing conditions, whereas STAT1 and STAT5 in Arid5a-deficient T cells were highly activated compared with those of WT T cells under the same conditions. These cells displayed the feature of antiinflammatory (Il10-expressing) CD4(+)T cells. Thus, we show a T cell-intrinsic role of Arid5a on fate decisions of naive CD4(+)T cells through selective stabilization of Stat3 mRNA.


Assuntos
Proteínas de Ligação a DNA/imunologia , Estabilidade de RNA/imunologia , RNA Mensageiro/imunologia , Fator de Transcrição STAT3/imunologia , Células Th17/imunologia , Fatores de Transcrição/imunologia , Animais , Proteínas de Ligação a DNA/genética , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Camundongos Knockout , Estabilidade de RNA/genética , RNA Mensageiro/genética , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Células Th17/citologia , Fatores de Transcrição/genética
16.
J Virol ; 90(7): 3530-42, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26792738

RESUMO

UNLABELLED: Hepatitis B virus (HBV) is a causative agent for chronic liver diseases such as hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). HBx protein encoded by the HBV genome plays crucial roles not only in pathogenesis but also in replication of HBV. Although HBx has been shown to bind to a number of host proteins, the molecular mechanisms by which HBx regulates HBV replication are largely unknown. In this study, we identified jumonji C-domain-containing 5 (JMJD5) as a novel binding partner of HBx interacting in the cytoplasm. DNA microarray analysis revealed that JMJD5-knockout (JMJD5KO) Huh7 cells exhibited a significant reduction in the expression of transcriptional factors involved in hepatocyte differentiation, such as HNF4A, CEBPA, and FOXA3. We found that hydroxylase activity of JMJD5 participates in the regulation of these transcriptional factors. Moreover, JMJD5KO Huh7 cells exhibited a severe reduction in HBV replication, and complementation of HBx expression failed to rescue replication of a mutant HBV deficient in HBx, suggesting that JMJD5 participates in HBV replication through an interaction with HBx. We also found that replacing Gly(135) with Glu in JMJD5 abrogates binding with HBx and replication of HBV. Moreover, the hydroxylase activity of JMJD5 was crucial for HBV replication. Collectively, these results suggest that direct interaction of JMJD5 with HBx facilitates HBV replication through the hydroxylase activity of JMJD5. IMPORTANCE: HBx protein encoded by hepatitis B virus (HBV) plays important roles in pathogenesis and replication of HBV. We identified jumonji C-domain-containing 5 (JMJD5) as a novel binding partner to HBx. JMJD5 was shown to regulate several transcriptional factors to maintain hepatocyte function. Although HBx had been shown to support HBV replication, deficiency of JMJD5 abolished contribution of HBx in HBV replication, suggesting that HBx-mediated HBV replication is largely dependent on JMJD5. We showed that hydroxylase activity of JMJD5 in the C terminus region is crucial for expression of HNF4A and replication of HBV. Furthermore, a mutant JMJD5 with Gly(135) replaced by Glu failed to interact with HBx and to rescue the replication of HBV in JMJD5-knockout cells. Taken together, our data suggest that interaction of JMJD5 with HBx facilitates HBV replication through the hydroxylase activity of JMJD5.


Assuntos
Vírus da Hepatite B/fisiologia , Hepatócitos/virologia , Histona Desmetilases/metabolismo , Interações Hospedeiro-Patógeno , Transativadores/metabolismo , Replicação Viral , Substituição de Aminoácidos , Linhagem Celular , Técnicas de Inativação de Genes , Histona Desmetilases/genética , Humanos , Mutagênese Sítio-Dirigida , Mapeamento de Interação de Proteínas , Proteínas Virais Reguladoras e Acessórias
17.
Nat Struct Mol Biol ; 21(7): 579-84, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24918548

RESUMO

Janus kinase-2 (JAK2) mediates signaling by various cytokines, including erythropoietin and growth hormone. JAK2 possesses tandem pseudokinase and tyrosine-kinase domains. Mutations in the pseudokinase domain are causally linked to myeloproliferative neoplasms (MPNs) in humans. The structure of the JAK2 tandem kinase domains is unknown, and therefore the molecular bases for pseudokinase-mediated autoinhibition and pathogenic activation remain obscure. Using molecular dynamics simulations of protein-protein docking, we produced a structural model for the autoinhibitory interaction between the JAK2 pseudokinase and kinase domains. A striking feature of our model, which is supported by mutagenesis experiments, is that nearly all of the disease mutations map to the domain interface. The simulations indicate that the kinase domain is stabilized in an inactive state by the pseudokinase domain, and they offer a molecular rationale for the hyperactivity of V617F, the predominant JAK2 MPN mutation.


Assuntos
Janus Quinase 2/fisiologia , Modelos Genéticos , Sítios de Ligação , Simulação por Computador , Humanos , Janus Quinase 2/química , Janus Quinase 2/genética , Modelos Moleculares , Estrutura Terciária de Proteína , Transdução de Sinais , Relação Estrutura-Atividade
18.
Spine (Phila Pa 1976) ; 32(9): 980-5, 2007 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-17450073

RESUMO

STUDY DESIGN: Prospective follow-up and retrospective review of 174 patients surgically treated for degenerative lumbar spinal stenosis. OBJECTIVE: To examine whether the type of leg pain syndrome associated with lumbar spinal stenosis is correlated with outcome. SUMMARY OF BACKGROUND DATA: Although classifying patients based on their leg pain syndrome is useful in planning surgical decompression, there is no validated method of classification and its prognostic significance remains unknown. METHODS: Based on the type of leg pain, the patients were classified into 2 groups: unilateral and bilateral. Improvement in functional status was evaluated using the Quebec Back Pain Disability Scale; the symptoms were rated on a visual analog scale and the change from baseline to 2-year evaluation was noted. Associations between score changes and baseline variables were examined using multivariate analysis. RESULTS: The type of leg pain was independently associated with improvements in function and leg symptom scores but was not associated with improvement in the back pain score. After surgery, patients with unilateral leg pain had significantly greater improvements in function and leg symptoms than patients with bilateral leg pain. CONCLUSION: In patients undergoing surgery for degenerative lumbar spinal stenosis, the preoperative type of leg pain predicts function and leg symptom outcomes.


Assuntos
Perna (Membro) , Vértebras Lombares , Dor/classificação , Estenose Espinal/classificação , Estenose Espinal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Dor nas Costas/classificação , Dor nas Costas/etiologia , Descompressão Cirúrgica/métodos , Feminino , Seguimentos , Humanos , Claudicação Intermitente/classificação , Claudicação Intermitente/etiologia , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Estudos Prospectivos , Radiculopatia/classificação , Radiculopatia/etiologia , Estudos Retrospectivos , Estenose Espinal/complicações , Síndrome , Resultado do Tratamento
19.
Spine (Phila Pa 1976) ; 31(13): 1484-90, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16741459

RESUMO

STUDY DESIGN: A prospective observational study of patients undergoing surgery for degenerative lumbar spinal stenosis. OBJECTIVE: To determine whether the long-term outcomes differ as a function of age and gender. SUMMARY OF BACKGROUND DATA: The long-term results of surgery for lumbar spinal stenosis are not well understood, and the patient characteristics that predispose patients to worse outcomes are unknown. METHODS: Seventy patients who underwent decompressive laminotomy with or without arthrodesis for degenerative lumbar spinal stenosis were prospectively studied at standard intervals after surgery with respect to symptom severity rated on a visual analog scale (VAS). RESULTS: The VAS scores for younger patients improved steadily for 3 or 6 months, after which the improvement was maintained until 60 months. The VAS scores for older patients showed a similar time course until 36 months, after which the VAS scores were worse compared with those for younger patients. The VAS scores for females were worse than those for males, in three symptoms queried, at one or more of the evaluation time points. CONCLUSION: In patients undergoing surgery for degenerative lumbar spinal stenosis, older age predicts a greater risk of late recurrence of symptoms, and women have higher VAS scores than men after surgery.


Assuntos
Descompressão Cirúrgica , Laminectomia , Vértebras Lombares/cirurgia , Dor/fisiopatologia , Fusão Vertebral , Estenose Espinal/fisiopatologia , Estenose Espinal/cirurgia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Prospectivos , Índice de Gravidade de Doença , Caracteres Sexuais , Fatores de Tempo , Resultado do Tratamento
20.
Am J Orthod Dentofacial Orthop ; 127(6): 730-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15953899

RESUMO

This article reports the successful treatment of a patient, aged 15 years 8 months, with a Class III malocclusion and oligodontia; a titanium screw was used for absolute anchorage during treatment. The patient had a concave profile because of mandibular excess and asymmetric spaces in both arches. Titanium screws were implanted in the retromolar area during intraoral vertical ramus osteotomy combined with LeFort I osteotomy. Absolute anchorage was provided with anchorage wires extending from the screws to the left canine and the right lateral incisor. After orthodontic space closure, the mandibular molars were moved mesially without lingual tipping of the mandibular incisors. A good interincisal relationship was achieved. Our results suggest that titanium screws and anchorage wires in the retromolar area are useful for the mesial movement of mandibular molars.


Assuntos
Anodontia/terapia , Parafusos Ósseos , Má Oclusão Classe III de Angle/terapia , Aparelhos Ortodônticos , Ortodontia Corretiva/instrumentação , Adolescente , Anodontia/complicações , Cefalometria/estatística & dados numéricos , Prótese Parcial Fixa , Feminino , Humanos , Má Oclusão Classe III de Angle/complicações , Má Oclusão Classe III de Angle/cirurgia , Mandíbula/cirurgia , Dente Molar , Desenho de Aparelho Ortodôntico , Fechamento de Espaço Ortodôntico/instrumentação , Osteotomia de Le Fort , Técnicas de Movimentação Dentária/instrumentação , Resultado do Tratamento
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