Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
PLoS One ; 19(5): e0299424, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38781172

RESUMO

Mutations in the non-structural protein regions of hepatitis C virus (HCV) are a cause of a non-sustained virological response (SVR) to treatment with direct-acting antivirals (DAAs) for chronic hepatitis; however, there are non-SVR cases without these mutations. In this study, we examined immune cell profiles in peripheral blood before and after ombitasvir/paritaprevir/ritonavir treatment and screened for genes that could be used to predict the therapeutic effects of DAAs. Fluorescence-activated cell sorting analysis indicated that the median frequencies of programmed cell death-1-positive (PD-1+) effector regulatory T cells (eTregs), PD-1+CD8+ T cells, and PD-1+Helper T cells were decreased significantly in SVR cases, but without significant changes in non-SVR cases. The frequency of PD-1+ naïve Tregs was significantly higher in the SVR group than in the non-SVR group before and after treatment. Similar results were found in patients treated with other DAAs (e.g., daclatasvir plus asunaprevir) and supported an immune response after HCV therapy. RNA-sequencing analysis indicated a significant increase in the expression of genes associated with the immune response in the SVR group, while genes related to intracellular and extracellular signal transduction were highly expressed in the non-SVR group. Therefore, we searched for genes associated with PD-1+ eTregs and CD8+ T cells that were significantly different between the SVR and non-SVR groups and found that T-box transcription factor 21 was associated with the non-SVR state. These results indicate that PD-1-related signaling pathways are associated with a non-SVR mechanism after DAAs treatment separate from mutation-related drug resistance.


Assuntos
Antivirais , Linfócitos T CD8-Positivos , Carbamatos , Hepacivirus , Hepatite C Crônica , Receptor de Morte Celular Programada 1 , Sulfonamidas , Linfócitos T Reguladores , Humanos , Antivirais/uso terapêutico , Masculino , Hepacivirus/efeitos dos fármacos , Hepacivirus/imunologia , Hepacivirus/genética , Feminino , Pessoa de Meia-Idade , Carbamatos/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Linfócitos T Reguladores/imunologia , Sulfonamidas/uso terapêutico , Sulfonamidas/farmacologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Hepatite C Crônica/sangue , Ciclopropanos/uso terapêutico , Valina/análogos & derivados , Prolina/análogos & derivados , Anilidas/uso terapêutico , Anilidas/farmacologia , Lactamas Macrocíclicas/uso terapêutico , Compostos Macrocíclicos/uso terapêutico , Compostos Macrocíclicos/farmacologia , Idoso , Ritonavir/uso terapêutico , Adulto , Quimioterapia Combinada , Linfócitos T Auxiliares-Indutores/imunologia , Imidazóis , Isoquinolinas , Pirrolidinas
2.
DEN Open ; 4(1): e334, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38264465

RESUMO

We describe a case of gastric cancer treated by photodynamic therapy (PDT) with talaporfin sodium using a novel simultaneous light-emitting method. An 82-year-old man was diagnosed with gastric cancer near the cardia with suspected deep submucosal invasion. Surgical resection was deemed high-risk owing to an underlying pulmonary disease. After ruling out endoscopic procedures due to intense fibrosis resulting from the scarring, PDT with talaporfin sodium was chosen. PDT was successfully conducted using an endoscope with simultaneous light emission. The patient experienced a complete response to the treatment and showed no signs of recurrence during follow-up. This case highlights the potential of PDT with talaporfin sodium as a viable alternative for challenging cases, particularly in patients unsuitable for surgery and endoscopic resection. Furthermore, the novel simultaneous light-emitting method may improve the efficiency of the procedure. This case demonstrates the potential of PDT in gastric cancer treatment, especially for high-risk patients.

3.
Eur J Pharm Sci ; 192: 106622, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37884100

RESUMO

This study aimed to develop a dissolution test that can predict the bioequivalence (BE) of enteric-coated pellet formulations. The original duloxetine hydrochloride capsule (reference formulation (RF); Cymbalta® 30 mg capsule) and four generic test formulations (two capsules (CP) and two orally disintegrating tablets (OD)) were used as model formulations. Clinical BE studies were conducted on 24-47 healthy male subjects under fasting conditions. Dissolution tests were performed using a compendial paddle method (PD) (paddle speed: 50 rpm) and a flow-through cell method (FTC) (flow rate: 4 mL/min). For a further test, cotton balls were added to the vessel to apply gentle mechanistic stress to the formulations, and paddle speed was reduced to 10 rpm (paddle with cotton ball method (PDCB)).All the dissolution tests were conducted with 0.01 M HCl (pH 2.0) for 0.5 h followed by 10 mM bicarbonate buffer solutions (pH 6.5) for 4 h. One each of the two CP and two OD showed BE with RF. PDCB was able to discriminate between BE and non-BE formulations, while this was not possible with PD and FTC. In PDCB, the cotton balls intermittently moved the pellets near the vessel bottom. PDCB is useful for predicting BE during formulation development.


Assuntos
Bicarbonatos , Masculino , Humanos , Equivalência Terapêutica , Comprimidos com Revestimento Entérico , Comprimidos , Cloridrato de Duloxetina , Solubilidade
4.
J Clin Invest ; 134(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37934601

RESUMO

Although most CD8+ T cells are equipped to kill infected or transformed cells, a subset may regulate immune responses and preserve self-tolerance. Here, we describe a CD8 lineage that is instructed to differentiate into CD8 T regulatory cells (Tregs) by a surprisingly restricted set of T cell receptors (TCRs) that recognize MHC-E (mouse Qa-1) and several dominant self-peptides. Recognition and elimination of pathogenic target cells that express these Qa-1-self-peptide complexes selectively inhibits pathogenic antibody responses without generalized immune suppression. Immunization with synthetic agonist peptides that mobilize CD8 Tregs in vivo efficiently inhibit antigraft antibody responses and markedly prolong heart and kidney organ graft survival. Definition of TCR-dependent differentiation and target recognition by this lineage of CD8 Tregs may open the way to new therapeutic approaches to inhibit pathogenic antibody responses.


Assuntos
Linfócitos T CD8-Positivos , Linfócitos T Reguladores , Camundongos , Animais , Receptores de Antígenos de Linfócitos T , Peptídeos , Tolerância Imunológica , Antígenos de Histocompatibilidade Classe I
5.
Hepatol Res ; 54(3): 315-319, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37817425

RESUMO

A 72-year-old man with metastatic hepatocellular carcinoma previously received first-line systemic therapy with atezolizumab plus bevacizumab. His disease was judged to be progressing 5 months after treatment initiation. Comprehensive genomic profiling revealed cytoplasmic mesenchymal-epithelial transition factor amplification. On the basis of an expert panel's recommendation, he received cabozantinib as second-line therapy. The tumors shrank markedly and continued to shrink 6 months after treatment. Comprehensive genomic profiling could provide useful information for selecting effective second-line treatments for patients with hepatocellular carcinoma after first-line immunotherapy.

6.
Intern Med ; 63(7): 929-935, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37495533

RESUMO

A 29-year-old man with severe ulcerative colitis and gastroduodenitis was initially treated with oral mesalamine and high-dose intravenous steroid therapy; however, his epigastralgia and vomiting did not improve. After initiating infliximab, the patient experienced prompt improvement in symptoms and inflammation. Although steroids were effective for the colon, they proved ineffective for gastroduodenal lesions, highlighting the necessity for molecular-targeted agents, such as infliximab, in these cases. The timing for administering such agents should be carefully considered.


Assuntos
Colite Ulcerativa , Duodenite , Gastrite , Masculino , Humanos , Adulto , Infliximab/efeitos adversos , Colite Ulcerativa/complicações , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Duodenite/tratamento farmacológico , Duodenite/diagnóstico , Duodenite/patologia , Gastrite/complicações , Progressão da Doença
7.
Inflamm Intest Dis ; 8(4): 133-142, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38115911

RESUMO

Introduction: Leucine-rich alpha-2-glycoprotein (LRG) is a potential biomarker for disease activity and reflects mucosal healing in patients with ulcerative colitis (UC). However, only a few studies have described a detailed sensitivity analysis of LRG in predicting mucosal healing in patients. This study aimed to evaluate the association between LRG and the endoscopic activity of UC and its predictability for mucosal healing and explore the utility and clinical application of LRG. Methods: The diagnostic accuracy of biomarkers, including LRG, in predicting the endoscopic activity of UC was evaluated. All consecutive patients who underwent total colonoscopy between April 2021 and September 2022 were included. The Mayo endoscopic subscore (MES) was used for assessing endoscopic activity. Furthermore, endoscopic remission was defined as an MES of ≤1. Clinical activity was evaluated based on stool frequency and bloody stool. Receiver operating characteristic curve analysis and binary logistic regression were performed to assess the diagnostic accuracy of the biomarkers. We evaluated LRG trends and treatment response in patients with MES ≥2 who underwent induction therapy. Results: This study comprised 214 patients. The proportions of endoscopically and clinically active patients were 33.6% and 49.1%, respectively. LRG had an area under the curve (AUC) of 0.856, with a higher diagnostic accuracy than other biomarkers, such as C-reactive protein, leukocyte, neutrophil, platelet, and albumin. The cutoff value for LRG was 15.6 µg/mL (sensitivity, 72.2%; specificity, 86.6%). Using the MES, patients with higher scores had higher LRG levels than those with lower scores. The cutoff value, AUC, sensitivity, and specificity varied with a higher AUC for left-sided colitis and pancolitis than for proctitis. Logistic regression analysis showed that LRG was an independent predictor of endoscopic remission using multivariate analysis, even with the factor of clinical activity. The change ratio of LRG pre- and post-treatment was statistically significant in the higher LRG group. Conclusion: LRG reflected endoscopic activity independently, regardless of clinical symptoms. An LRG below the cutoff value could indicate a significantly low probability of endoscopic activity in asymptomatic patients, and follow-up endoscopy (not for cancer screening) may be unnecessary. Furthermore, a higher LRG level might be more useful as an indicator of treatment efficacy.

8.
Intern Med ; 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37839881

RESUMO

We herein report a rare case of idiopathic portal hypertension (IPH)-like disease that developed after allogeneic hematopoietic stem cell transplantation (allo-HSCT). A 53-year-old woman who underwent allo-HSCT for acute myeloid leukemia showed portal hypertension with radiological and histopathological findings consistent with IPH, distinct from veno-occlusive disease (VOD) and graft-versus-host disease (GVHD) of the liver. This case highlights the importance of considering IPH-like disease as a potential cause of portal hypertension after allo-HSCT. Awareness of this complication can aid in the early diagnosis and appropriate management of patients post allo-HSCT.

10.
Eur J Pharm Sci ; 180: 106326, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347443

RESUMO

The purpose of this study was to develop a bicarbonate buffer flow-through cell (FTC) dissolution test. Mesalazine colon targeting tablets of a generic development product (test formulation, TF; Mesalazine 400 mg tablet) and the original product (reference formulation, RF; Asacol® 400 mg tablet) were used as model formulations. A clinical bioequivalence (BE) study was conducted on 48 healthy male subjects under fasting conditions. The oral absorption time profiles were calculated by point-area deconvolution. The compendial paddle and FTC apparatus were used for dissolution tests. Bicarbonate or phosphate-citrate buffer solutions (McIlvaine buffer) were used as the dissolution media. A floating lid was used to maintain the pH value of the bicarbonate buffer solution in the vessel (paddle) or the reservoir (FTC). In the development of bicarbonate FTC method, the pH changes of bicarbonate buffer solution (pH 5.5-7.5; 5-50 mM bicarbonate) were evaluated. For the evaluation of colon targeting tablets, the dissolution profiles of TF and RF were measured at a pH of 7.5. The TF and RF formulations were exposed to 0.01 HCl (pH 2.0) for 2 h before pH 7.5. In the clinical BE study, drug dissolution started 4-8 h after oral administration and continued slowly more than 10 h. Both the area under the curve (AUC) and maximum plasma concentration (Cmax) of TF were approximately twice as high as those of RF. In the development of the bicarbonate FTC method, the pH change of the bicarbonate buffer solution was suppressed by the floating lid within ∆pH < 0.1 over 10 h. In the dissolution test of McIlvaine buffer solutions, TF and RF showed faster disintegration and higher dissolution than those observed in the clinical BE study. When using the paddle apparatus the dissolution profiles of TF and RF in both buffer solutions were not consistent with those of the clinical result. In bicarbonate FTC, the disintegration time, dissolution rate, and dissolution inequivalence between TF and RF were consistent with the results of the clinical BE study. In conclusion, the bicarbonate FTC method was constructed for the first time in this study. This method is simple and practically useful for predicting in vivo performance of colon targeting tablets during drug development.


Assuntos
Bicarbonatos , Colo , Masculino , Humanos , Concentração de Íons de Hidrogênio , Comprimidos , Liberação Controlada de Fármacos , Solubilidade
11.
Cell Mol Gastroenterol Hepatol ; 14(4): 925-944, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35787976

RESUMO

BACKGROUND & AIMS: The lipid oxidation is a key factor for damaging hepatocytes and causing cell death. However, the mechanisms underlying hepatocyte death and the role of the most popular lipid peroxidation product 4-hydroxy-2-nonenal (HNE) in nonalcoholic steatohepatitis (NASH) remains unclear. METHODS: We demonstrated using hepatoma cell lines, a NASH mouse model, HNE-treated monkeys, and biopsy specimens from patients with NASH that HNE induced hepatocyte death by disintegrating the lysosomal limiting membrane. RESULTS: The degree of HNE deposition in human NASH hepatocytes was more severe in cases with high lobular inflammation, ballooning, and fibrosis scores, and was associated with enlargement of the staining of lysosomes in hepatocytes. In in vitro experiments, HNE activated µ-calpain via G-protein coupled receptor (GPR) 120. The resultant rupture/permeabilization of the lysosomal limiting membrane induced the leakage of cathepsins from lysosomes and hepatocyte death. The blockade of G-protein coupled receptor 120 (GPR120) or µ-calpain expression suppressed lysosomal membrane damage and hepatocyte death by HNE. Alda-1, which activates aldehyde dehydrogenase 2 to degrade HNE, prevented HNE-induced hepatocyte death. Intravenous administration of HNE to monkeys for 6 months resulted in hepatocyte death by a mechanism similar to that of cultured cells. In addition, intraperitoneal administration of Alda-1 to choline-deficient, amino-acid defined treated mice for 8 weeks inhibited HNE deposition, decreased liver inflammation, and disrupted lysosomal membranes in hepatocytes, resulting in improvement of liver fibrosis. CONCLUSIONS: These results provide novel insights into the mechanism of hepatocyte death in NASH and will contribute to the development of new therapeutic strategies for NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Aldeído Desidrogenase/metabolismo , Animais , Catepsinas/metabolismo , Colina/metabolismo , Hepatócitos/metabolismo , Humanos , Inflamação/patologia , Lipídeos , Lisossomos/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/patologia
12.
Nat Commun ; 13(1): 3123, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35660746

RESUMO

The behaviors and fates of immune cells in cancer patients, such as dysfunction and stem-like states leading to memory formation in T cells, are in intense focus of investigation. Here we show, by post hoc analysis of peripheral blood lymphocytes of hepatocellular carcinoma patients previously undergoing vaccination with tumour-associated antigen-derived peptides in our clinical trials (registration numbers UMIN000003511, UMIN000004540, UMIN000005677, UMIN000003514 and UMIN000005678), that induced peptide-specific T cell responses may persist beyond 10 years following vaccination. Tracking TCR clonotypes at the single cell level reveals in two patients that peptide-specific long-lasting CD8+ T cells acquire an effector memory phenotype that associates with cell cycle-related genes (CCNA2 and CDK1), and are characterized by high expression of IL7R, SELL, and NOSIP along with a later stage promotion of the AP-1 transcription factor network (5 years or more past vaccination). We conclude that effective anti-tumor immunity is governed by potentially proliferative memory T cells, specific to cancer antigens.


Assuntos
Vacinas Anticâncer , Neoplasias , Linfócitos T CD8-Positivos , Humanos , Neoplasias/metabolismo , Peptídeos/metabolismo , Vacinas de Subunidades Antigênicas/uso terapêutico
13.
Proc Natl Acad Sci U S A ; 119(18): e2200757119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35482921

RESUMO

Regulatory T cells (Treg) can impede antitumor immunity and currently represent a major obstacle to effective cancer immunotherapy. Targeting tumor-infiltrating regulatory Treg while sparing systemic Treg represents an optimal approach to this problem. Here, we provide evidence that the interleukin 23 receptor (IL23R) expressed by tumor-infiltrating Treg promotes suppressive activity. Disruption of the IL23R results in increased responsiveness of destabilized Treg to the IL12 cytokine, the production of γ-interferon, and the recruitment of CD8 T cells that inhibit tumor growth. Since the Treg destabilization pathway that is initiated by IL23R blockade is distinct and independent from the destabilization pathway coupled to glucocorticoid-induced TNFR-related protein (GITR) activation, we examined the impact of the coordinate induction of the two destabilization pathways on antitumor immune responses. Combined GITR and IL23R antibody treatment of mice inoculated with MC38 tumors resulted in robust and synergistic antitumor responses. These findings indicate that the delineation of independent Treg destabilization pathways may allow improved approaches to the development of combination immunotherapy for cancers.


Assuntos
Neoplasias , Linfócitos T Reguladores , Anticorpos Bloqueadores , Humanos , Fatores Imunológicos/metabolismo , Imunoterapia , Interleucina-23/metabolismo , Neoplasias/metabolismo
14.
Mol Oncol ; 15(8): 2203-2218, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33834612

RESUMO

The malignant nature of hepatocellular carcinoma (HCC) is closely related to the presence of cancer stem cells (CSCs). Bone morphologic protein 9 (BMP9), a member of the transforming growth factor-beta (TGF-ß) superfamily, was recently reported to be involved in liver diseases including cancer. We aimed to elucidate the role of BMP9 signaling in HCC-CSC properties and to assess the therapeutic effect of BMP receptor inhibitors in HCC. We have identified that high BMP9 expression in tumor tissues or serum from patients with HCC leads to poorer outcome. BMP9 promoted CSC properties in epithelial cell adhesion molecule (EpCAM)-positive HCC subtype via enhancing inhibitor of DNA-binding protein 1 (ID1) expression in vitro. Additionally, ID1 knockdown significantly repressed BMP9-promoted HCC-CSC properties by suppressing Wnt/ß-catenin signaling. Interestingly, cells treated with BMP receptor inhibitors K02288 and LDN-212854 blocked HCC-CSC activation by inhibiting BMP9-ID1 signaling, in contrast to cells treated with the TGF-ß receptor inhibitor galunisertib. Treatment with LDN-212854 suppressed HCC tumor growth by repressing ID1 and EpCAM in vivo. Our study demonstrates the pivotal role of BMP9-ID1 signaling in promoting HCC-CSC properties and the therapeutic potential of BMP receptor inhibitors in treating EpCAM-positive HCC. Therefore, targeting BMP9-ID1 signaling could offer novel therapeutic options for patients with malignant HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Fator 2 de Diferenciação de Crescimento/metabolismo , Proteína 1 Inibidora de Diferenciação/metabolismo , Neoplasias Hepáticas/patologia , Células-Tronco Neoplásicas/patologia , Transdução de Sinais , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Estudos de Coortes , Técnicas de Silenciamento de Genes , Humanos , Proteína 1 Inibidora de Diferenciação/genética , Neoplasias Hepáticas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Via de Sinalização Wnt
15.
Cytotherapy ; 23(2): 137-145, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32907781

RESUMO

BACKGROUND AIMS: Immunotherapy is effective for many types of cancer, but its benefits in advanced pancreatic cancer, which has a poor prognosis, are not well established. In this study, the authors examined the effects of adoptive T-cell immunotherapy (ATI) on immune cell profiles and prognosis in patients with unresectable advanced pancreatic cancer. METHODS: Seventy-seven patients with unresectable advanced pancreatic cancer were treated with six cycles of αß T cells alone or in combination with chemotherapy or chemoradiation. Immune cell profiles in peripheral blood samples obtained before and after treatment were comprehensively evaluated by flow cytometry. Furthermore, associations between changes in immune cell frequencies and prognosis were determined. RESULTS: ATI prolonged survival to 18.7 months compared with previous estimates of 6.2-11.1 months for patients treated with chemotherapy alone. ATI decreased CD3+CD4+CD8- T cell frequency in peripheral blood and increased CD3+CD4-CD8+ T cell frequency. An increase in CD3+ T cells and CD3+TCRγδ- T cells in peripheral blood after treatment was associated with a good prognosis. CONCLUSIONS: ATI altered the immune profile in peripheral blood, including CD3+CD4-CD8+ T cells, and improved prognosis in pancreatic cancer.


Assuntos
Imunoterapia Adotiva , Neoplasias Pancreáticas , Linfócitos T CD8-Positivos , Citometria de Fluxo , Humanos , Imunoterapia , Neoplasias Pancreáticas/terapia
16.
Transl Oncol ; 13(7): 100777, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32413834

RESUMO

Dendritic cell (DC)-based immunotherapies are believed to help eradicate residual tumor cells, including hepatocellular carcinoma (HCC). Here, we assessed the safety and clinical response to OK432-stimulated monocyte-derived DCs (MoDCs) in treating HCC after radiofrequency ablation (RFA). MoDCs were derived from 30 HCC patients in the presence of interleukin-4 and granulocyte-macrophage colony stimulating factor for 5 days and then cultured for 2 more days in the medium (basic protocol) or stimulated with OK432. On day 7, DCs were harvested and percutaneously injected into HCC tumors after RFA. We observed no grade 3 or 4 National Cancer Institute Common Toxicity Criteria adverse events. Kaplan-Meier analysis indicated that patients treated with RFA + OK432-stimulated DCs transfer had longer recurrence-free survival than those treated with RFA + basic-protocol DCs (median: 24.8 vs 13.0 months; P = .003). RFA with DC infusion can enhance various tumor-associated antigen (TAA)-specific T-cell responses. Additionally, the 5-year RFS rate for patients with significantly increased TAA-specific T-cell responses was much higher than for other patients (50.0% vs. 7.7%; P = .030). Our study provides useful information for development of HCC immunotherapies (trial registration: UMIN000001701).

18.
Cell Rep ; 29(7): 1848-1861.e6, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31722202

RESUMO

Follicular regulatory T (TFR) cells are a specialized suppressive subset that controls the germinal center (GC) response and maintains humoral self-tolerance. The mechanisms that maintain TFR lineage identity and suppressive activity remain largely unknown. Here, we show that expression of Blimp1 by FoxP3+ TFR cells is essential for TFR lineage stability, entry into the GC, and expression of regulatory activity. Deletion of Blimp1 in TFR cells reduced FoxP3 and CTLA-4 expression and increased pro-inflammatory cytokines and spontaneous production of autoantibodies, including elevated IgE. Maintenance of TFR stability reflected Blimp1-dependent repression of the IL-23R-STAT3 axis and activation of the CD25-STAT5 pathway, while silenced IL-23R-STAT3 or increased STAT5 activation rescued the Blimp1-deficient TFR phenotype. Blimp1-dependent control of CXCR5/CCR7 expression also regulated TFR homing into the GC. These findings uncover a Blimp1-dependent TFR checkpoint that enforces suppressive activity and acts as a gatekeeper of GC entry.


Assuntos
Regulação da Expressão Gênica/imunologia , Centro Germinativo/imunologia , Fator 1 de Ligação ao Domínio I Regulador Positivo/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular , Centro Germinativo/citologia , Humanos , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/imunologia , Camundongos , Camundongos Transgênicos , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Receptores CCR7/genética , Receptores CCR7/imunologia , Receptores CXCR5/genética , Receptores CXCR5/imunologia , Receptores de Interleucina/genética , Receptores de Interleucina/imunologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/imunologia , Transdução de Sinais/genética , Linfócitos T Reguladores/citologia
19.
Hepatology ; 70(1): 25-39, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30938456

RESUMO

Dendritic cells (DCs) are antigen-presenting cells with a central role in host immune response. This study analyzed gene expression and DC function in hepatitis B virus (HBV) patients, functions impaired because of HBV, and identified the genes related to these functions. Peripheral blood mononuclear cells from 64 HBV patients and 19 healthy controls were analyzed. Peripheral blood DCs were stained with antibodies against human leukocyte antigen-DR/Lin-1/CD123/CD11c and separated into plasmacytoid DCs (pDCs) and myeloid DCs by fluorescence-activated cell sorting. Using an interferon-gamma enzyme-linked immunospot assay, we analyzed antigen-specific response in HBV-infected patients. Regarding DC function, we analyzed antigen-presenting capacity, cell migration capacity, phagocytic capacity, and cytokine production capacity. DC gene expression was analyzed by microarray to identify genes related to DC function. No difference was found in the number of DCs in peripheral blood between healthy participants and HBV patients. In cell-surface marker analysis, CD80, CD83, CD86, CD40, and C-C motif chemokine receptor 7 expression levels in pDCs were related to the HBV-specific T-cell response. DCs from HBV patients exhibited decreases in antigen-presenting capacity, migration capacity, and cytokine production capacity. In gene expression analysis, immune-related genes with greatly reduced expression levels in chronic hepatitis B patients were identified. Of these genes, interleukin (IL)-6 signal transducer (IL6ST) expression level positively correlated with DC surface marker expression level. Adjustment of IL6ST expression level in DCs and treatment with oncostatin M resulted in recovery of DC function. Conclusion: IL6ST expression was identified as one cause of decline in DC function in HBV patients. Adjustment of IL6 family cytokine signaling may be useful for recovering reduced DC function in HBV infection.


Assuntos
Células Dendríticas/metabolismo , Hepatite B/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T Citotóxicos/fisiologia
20.
Adv Immunol ; 140: 1-20, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30366517

RESUMO

Regulatory T cells are central mediators of immune regulation and play an essential role in the maintenance of immune homeostasis in the steady state and under pathophysiological conditions. Disruption of CD8 Treg-dependent recognition of Qa-1-restricted self-antigens can result in dysregulated immune responses, tissue damage, autoimmune disease and cancer. Recent progress in studies on regulatory T cells of the CD8 lineage has provided new biological insight into this specialized regulatory T cell subpopulation. Identification of the Helios transcription factor as an essential control element for the differentiation and function of CD8 regulatory T cells has led to a better understanding of the unique genetic program of these cells. Recent analyses of T-cell receptor usage and antigen recognition by Qa-1-restricted CD8 Treg have provided additional insight into the unusual biological function of this regulatory CD8 lineage. Here we summarize recent advances in our understanding of CD8 regulatory T cells with emphasis on lineage commitment, differentiation and stability.


Assuntos
Doenças Autoimunes/imunologia , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Animais , Autoantígenos , Antígenos CD8/metabolismo , Diferenciação Celular , Movimento Celular , Regulação da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/metabolismo , Homeostase , Humanos , Fator de Transcrição Ikaros/genética , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA