Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Nanoscale ; 16(17): 8563-8572, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38600859

RESUMEN

Handedness inversion of supramolecular chirality and circularly polarized luminescence (CPL) in assembled systems containing more than two components with higher complexity is of prominent importance to simulate biological multicomponent species and design advanced chiral materials, but it remains a considerable challenge. Herein, we have successfully developed ternary co-assembly systems based on aromatic amino acids, vinylnaphthalene derivatives and 1,2,4,5-tetracyanobenzene with effective chirality transfer. Notably, the handedness of supramolecular chirality and CPL can be readily inverted by changing the residues of amino acids, the substituents of achiral vinylnaphthalene derivatives, or by adjusting the stoichiometric ratio. The hydrogen bonds, charge transfer interactions, and steric hindrance are proved to be the crucial factors for the chirality inversion. This flexible control over chirality not only offers insights into developing multicomponent chiral materials with desirable handedness from simple molecular building blocks, but also is of practical value for use in chiroptics, chiral sensing, and photoelectric devices.

2.
Elife ; 122023 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-36688525

RESUMEN

Autoimmune inflammation is characterized by tissue infiltration and expansion of antigen-specific T cells. Although this inflammation is often limited to specific target tissues, it remains yet to be explored whether distinct affected sites are infiltrated with the same, persistent T cell clones. Here, we performed CyTOF analysis and T cell receptor (TCR) sequencing to study immune cell composition and (hyper-)expansion of circulating and joint-derived Tregs and non-Tregs in juvenile idiopathic arthritis (JIA). We studied different joints affected at the same time, as well as over the course of relapsing-remitting disease. We found that the composition and functional characteristics of immune infiltrates are strikingly similar between joints within one patient, and observed a strong overlap between dominant T cell clones, especially Treg, of which some could also be detected in circulation and persisted over the course of relapsing-remitting disease. Moreover, these T cell clones were characterized by a high degree of sequence similarity, indicating the presence of TCR clusters responding to the same antigens. These data suggest that in localized autoimmune disease, there is autoantigen-driven expansion of both Teffector and Treg clones that are highly persistent and are (re)circulating. These dominant clones might represent interesting therapeutic targets.


Asunto(s)
Artritis Juvenil , Humanos , Linfocitos T Reguladores , Inflamación , Receptores de Antígenos de Linfocitos T , Células Clonales
4.
Nat Commun ; 12(1): 227, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33431814

RESUMEN

The clinical relevance of immune landscape intratumoural heterogeneity (immune-ITH) and its role in tumour evolution remain largely unexplored. Here, we uncover significant spatial and phenotypic immune-ITH from multiple tumour sectors and decipher its relationship with tumour evolution and disease progression in hepatocellular carcinomas (HCC). Immune-ITH is associated with tumour transcriptomic-ITH, mutational burden and distinct immune microenvironments. Tumours with low immune-ITH experience higher immunoselective pressure and escape via loss of heterozygosity in human leukocyte antigens and immunoediting. Instead, the tumours with high immune-ITH evolve to a more immunosuppressive/exhausted microenvironment. This gradient of immune pressure along with immune-ITH represents a hallmark of tumour evolution, which is closely linked to the transcriptome-immune networks contributing to disease progression and immune inactivation. Remarkably, high immune-ITH and its transcriptomic signature are predictive for worse clinical outcome in HCC patients. This in-depth investigation of ITH provides evidence on tumour-immune co-evolution along HCC progression.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Progresión de la Enfermedad , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , ADN/genética , Edición Génica , Redes Reguladoras de Genes , Humanos , Leucocitos Mononucleares/metabolismo , Filogenia , Pronóstico , ARN/genética , Análisis de Supervivencia , Transcriptoma/genética , Resultado del Tratamiento , Microambiente Tumoral/inmunología
7.
Front Immunol ; 11: 615091, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33584702

RESUMEN

Intravesical Bacillus Calmette-Guerin (BCG) is an effective immunotherapy for non-muscle invasive bladder cancer (NMIBC). However, recurrence and progression remain frequent warranting deeper insights into its mechanism. We herein comprehensively profiled blood and tissues obtained from NMIBC patients before, during and after BCG treatment using cytometry by time-of-flight (CyTOF) and RNA sequencing to identify the key immune subsets crucial for anti-tumor activity. We observed the temporal changes of peripheral immune subsets including NKT cells, central memory CD4+ T cells, CD8+ T cells and regulatory T cells (Treg) during the course of BCG. Gene expression analysis revealed enriched immune pathways involving in T cell activation and chemotaxis, as well as a more diversified T cell receptor repertoire in post-BCG tissues. Moreover, tissue multiplexed-immunofluorescence (mIF) showed baseline densities of non-Treg and CD8+PD-1+ T cells were predictive of response and better recurrence-free survival after BCG. Remarkably, post-BCG tissues from responders were found to be infiltrated with more active CD8+PD-1- T cells and non-Treg CD4+FOXP3- T cells; but increased exhausted CD8+PD-1+ T cells were found in non-responders. Taken together, we identified predictive biomarkers for response and uncovered the post-treatment expansion of exhausted PD-1+CD8+ T cells as key to BCG resistance, which could potentially be restored by combining with anti-PD-1 immunotherapy.


Asunto(s)
Vacuna BCG/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico , Inmunoterapia Activa , Subgrupos Linfocitarios/inmunología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Carcinoma de Células Transicionales/inmunología , Carcinoma de Células Transicionales/terapia , Quimiotaxis , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Citometría de Imagen/instrumentación , Citometría de Imagen/métodos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia , Activación de Linfocitos , Recuento de Linfocitos , Subgrupos Linfocitarios/efectos de los fármacos , Receptor de Muerte Celular Programada 1/análisis , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptores de Antígenos de Linfocitos T/análisis , Análisis de la Célula Individual , Subgrupos de Linfocitos T/química , Subgrupos de Linfocitos T/inmunología , Factores de Tiempo , Transcriptoma , Escape del Tumor , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/terapia
8.
Ann Rheum Dis ; 78(12): 1712-1721, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31540934

RESUMEN

OBJECTIVES: Biologics treatment with antitumour necrosis factor alpha (TNFα) is efficacious in patients with juvenile idiopathic arthritis (JIA). Despite displaying clinical inactivity during treatment, many patients will flare on cessation of therapy. The inability to definitively discriminate patients who will relapse or continue to remain in remission after therapy withdrawal is currently a major unmet medical need. CD4 T cells have been implicated in active disease, yet how they contribute to disease persistence despite treatment is unknown. METHODS: We interrogated the circulatory reservoir of CD4+ immune subsets at the single-cell resolution with mass cytometry (cytometry by time of flight) of patients with JIA (n=20) who displayed continuous clinical inactivity for at least 6 months with anti-TNFα and were subsequently withdrawn from therapy for 8 months, and scored as relapse or remission. These patients were examined prior to therapy withdrawal for putative subsets that could discriminate relapse from remission. We verified on a separate JIA cohort (n=16) the dysregulation of these circulatory subsets 8 months into therapy withdrawal. The immunological transcriptomic signature of CD4 memory in relapse/remission patients was examined with NanoString. RESULTS: An inflammatory memory subset of CD3+CD4+CD45RA-TNFα+ T cells deficient in immune checkpoints (PD1-CD152-) was present in relapse patients prior to therapy withdrawal. Transcriptomic profiling reveals divergence between relapse and remission patients in disease-centric pathways involving (1) T-cell receptor activation, (2) apoptosis, (3) TNFα, (4) nuclear factor-kappa B and (5) mitogen-activated protein kinase signalling. CONCLUSIONS: A unique discriminatory immunomic and transcriptomic signature is associated with relapse patients and may explain how relapse occurs.


Asunto(s)
Artritis Juvenil/inmunología , Productos Biológicos/uso terapéutico , Linfocitos T CD4-Positivos/inmunología , Inmunidad Celular , Inducción de Remisión/métodos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Privación de Tratamiento , Adolescente , Artritis Juvenil/tratamiento farmacológico , Artritis Juvenil/patología , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Recurrencia
9.
Gut ; 68(2): 335-346, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29440463

RESUMEN

OBJECTIVES: Yttrium-90 (Y90)-radioembolisation (RE) significantly regresses locally advanced hepatocellular carcinoma and delays disease progression. The current study is designed to deeply interrogate the immunological impact of Y90-RE, which elicits a sustained therapeutic response. DESIGN: Time-of-flight mass cytometry and next-generation sequencing (NGS) were used to analyse the immune landscapes of tumour-infiltrating leucocytes (TILs), tumour tissues and peripheral blood mononuclear cells (PBMCs) at different time points before and after Y90-RE. RESULTS: TILs isolated after Y90-RE exhibited signs of local immune activation: higher expression of granzyme B (GB) and infiltration of CD8+ T cells, CD56+ NK cells and CD8+ CD56+ NKT cells. NGS confirmed the upregulation of genes involved in innate and adaptive immune activation in Y90-RE-treated tumours. Chemotactic pathways involving CCL5 and CXCL16 correlated with the recruitment of activated GB+CD8+ T cells to the Y90-RE-treated tumours. When comparing PBMCs before and after Y90-RE, we observed an increase in tumour necrosis factor-α on both the CD8+ and CD4+ T cells as well as an increase in percentage of antigen-presenting cells after Y90-RE, implying a systemic immune activation. Interestingly, a high percentage of PD-1+/Tim-3+CD8+ T cells coexpressing the homing receptors CCR5 and CXCR6 denoted Y90-RE responders. A prediction model was also built to identify sustained responders to Y90-RE based on the immune profiles from pretreatment PBMCs. CONCLUSION: High-dimensional analysis of tumour and systemic immune landscapes identified local and systemic immune activation that corresponded to the sustained response to Y90-RE. Potential biomarkers associated with a positive clinical response were identified and a prediction model was built to identify sustained responders prior to treatment.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/radioterapia , Leucocitos Mononucleares/inmunología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/radioterapia , Radioisótopos de Itrio , Células Presentadoras de Antígenos/inmunología , Biomarcadores de Tumor/inmunología , Quimiocina CCL5/inmunología , Quimiocina CXCL16/inmunología , Progresión de la Enfermedad , Femenino , Citometría de Flujo/métodos , Granzimas/inmunología , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Singapur , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/inmunología
10.
Gut ; 68(5): 916-927, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29970455

RESUMEN

BACKGROUND AND AIMS: Chronic inflammation induced by chronic hepatitis B virus (HBV) infection increases the risk of hepatocellular carcinoma (HCC). However, little is known about the immune landscape of HBV-related HCC and its influence on the design of effective cancer immunotherapeutics. METHODS: We interrogated the immune microenvironments of HBV-related HCC and non-viral-related HCC using immunohistochemistry and cytometry by time-of-flight (CyTOF). On identifying unique immune subsets enriched in HBV-related HCC, we further interrogated their phenotypes and functions using next-generation sequencing (NGS) and in vitro T-cell proliferation assays. RESULTS: In-depth interrogation of the immune landscapes showed that regulatory T cells (TREG) and CD8+ resident memory T cells (TRM) were enriched in HBV-related HCC, whereas Tim-3+CD8+ T cells and CD244+ natural killer cells were enriched in non-viral-related HCC. NGS of isolated TREG and TRM from HBV-related HCC and non-viral-related HCC identified distinct functional signatures associated with T-cell receptor signalling, T-cell costimulation, antigen presentation and programmed cell death protein 1 (PD-1) signalling. TREG and TRM from HBV-related HCC expressed more PD-1 and were functionally more suppressive and exhausted than those from non-virus-related HCC. Furthermore, immunosuppression by PD-1+ TREG could be reversed with anti-PD-1 blockade. Using multiplexed tissue immunofluorescence, we further demonstrated that TREG and TRM contributed to overall patient survival: TREG were associated with a poor prognosis and TRM were associated with a good prognosis in HCC. CONCLUSION: We have shown that the HBV-related HCC microenvironment is more immunosuppressive and exhausted than the non-viral-related HCC microenvironment. Such in-depth understanding has important implications in disease management and appropriate application of immunotherapeutics.


Asunto(s)
Linfocitos T CD8-positivos/fisiología , Carcinoma Hepatocelular/virología , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/inmunología , Neoplasias Hepáticas/virología , Carcinoma Hepatocelular/patología , Hepatitis B Crónica/patología , Humanos , Neoplasias Hepáticas/patología , Técnicas de Cultivo de Tejidos , Microambiente Tumoral
11.
Proc Natl Acad Sci U S A ; 114(29): E5900-E5909, 2017 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-28674001

RESUMEN

The recent development of immunotherapy as a cancer treatment has proved effective over recent years, but the precise dynamics between the tumor microenvironment (TME), nontumor microenvironment (NTME), and the systemic immune system remain elusive. Here, we interrogated these compartments in hepatocellular carcinoma (HCC) using high-dimensional proteomic and transcriptomic analyses. By time-of-flight mass cytometry, we found that the TME was enriched in regulatory T cells (Tregs), tissue resident memory CD8+ T cells (TRMs), resident natural killer cells (NKRs), and tumor-associated macrophages (TAMs). This finding was also validated with immunofluorescence staining on Foxp3+CD4+ and PD-1+CD8+ T cells. Interestingly, Tregs and TRMs isolated from the TME expressed multiple markers for T-cell exhaustion, including PD-1, Lag-3, and Tim-3 compared with Tregs and TRMs isolated from the NTME. We found PD-1+ TRMs were the predominant T-cell subset responsive to anti-PD-1 treatment and significantly reduced in number with increasing HCC tumor progression. Furthermore, T-bet was identified as a key transcription factor, negatively correlated with PD-1 expression on memory CD8+ T cells, and the PD-1:T-bet ratio increased upon exposure to tumor antigens. Finally, transcriptomic analysis of tumor and adjacent nontumor tissues identified a chemotactic gradient for recruitment of TAMs and NKRs via CXCR3/CXCL10 and CCR6/CCL20 pathways, respectively. Taken together, these data confirm the existence of an immunosuppressive gradient across the TME, NTME, and peripheral blood in primary HCC that manipulates the activation status of tumor-infiltrating leukocytes and renders them immunocompromised against tumor cells. By understanding the immunologic composition of this gradient, more effective immunotherapeutics for HCC may be designed.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/metabolismo , Microambiente Tumoral/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Carcinoma Hepatocelular/genética , Factores de Transcripción Forkhead/metabolismo , Perfilación de la Expresión Génica , Humanos , Tolerancia Inmunológica/inmunología , Antígenos Comunes de Leucocito/inmunología , Antígenos Comunes de Leucocito/metabolismo , Leucocitos/inmunología , Leucocitos/patología , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/patología , Neoplasias Hepáticas/genética , Receptor de Muerte Celular Programada 1/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Proteómica , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología
12.
13.
Cytometry A ; 87(4): 369-74, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25645694

RESUMEN

CyTOF enables the study of the immune system with a complexity, depth, and multidimensionality never achieved before. However, the full potential of using CyTOF can be limited by scarce cell samples. Barcoding strategies developed based on direct labeling of cells using maleimido-monoamide-DOTA (m-DOTA) provide a very useful tool. However, using m-DOTA has some inherent problems, mainly associated with signal intensity. This may be a source of uncertainty when samples are multiplexed. As an alternative or complementary approach to m-DOTA, conjugating an antibody, specific for a membrane protein present on most immune cells, with different isotopes could address the issues of stability and signal intensity needed for effective barcoding. We chose for this purpose CD45, and designed experiments to address different types of cultures and the ability to detect extra- and intra-cellular targets. We show here that our approach provides an useful alternative to m-DOTA in terms of sensitivity, specificity, flexibility, and user-friendliness. Our manuscript provides details to effectively barcode immune cells, overcoming limitations in current technology and enabling the use of CyTOF with scarce samples (for instance precious clinical samples).


Asunto(s)
Citometría de Flujo/métodos , Antígenos Comunes de Leucocito/análisis , Espectrometría de Masas/métodos , Adulto , Anticuerpos/inmunología , Humanos , Antígenos Comunes de Leucocito/inmunología , Leucocitos Mononucleares/citología , Coloración y Etiquetado
14.
Nat Commun ; 4: 2359, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23965983

RESUMEN

The p53 tumour suppressor has an important role in cancer cells. Here we show that p53 regulates expression of major histocompatibility complex I on the cell surface. We show that the tumour cell line HCT116, which lacks p53 exhibits significantly lower major histocompatibility complex I expression than its wild-type counterpart. Using a combination of chromatin immunoprecipitation sequencing and gene expression analysis, we demonstrate that p53 upregulates expression of endoplasmic reticulum aminopeptidase 1 by binding to its cognate response element in the ERAP1 gene. Silencing of p53 decreases endoplasmic reticulum aminopeptidase 1 protein levels and therefore major histocompatibility complex I expression. We further show that this mechanism operates in A549 cells infected with H1N1 influenza virus, in which H1N1 activates p53, leading to endoplasmic reticulum aminopeptidase 1 upregulation and a corresponding increase in major histocompatibility complex I expression. Our study suggests a previously unrecognized link between p53 function and the immunosurveillance of cancer and infection.


Asunto(s)
Aminopeptidasas/inmunología , Retículo Endoplásmico/metabolismo , Antígenos de Histocompatibilidad Clase I/inmunología , Proteína p53 Supresora de Tumor/metabolismo , Aminopeptidasas/biosíntesis , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Retículo Endoplásmico/inmunología , Células HCT116 , Antígenos de Histocompatibilidad Clase I/biosíntesis , Humanos , Imidazoles/metabolismo , Vigilancia Inmunológica/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Antígenos de Histocompatibilidad Menor , Piperazinas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño , Proteína p53 Supresora de Tumor/genética , Regulación hacia Arriba
15.
J Proteome Res ; 10(10): 4535-46, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-21842849

RESUMEN

Gastric fluid is a source of gastric cancer biomarkers. However, very little is known about the normal gastric fluid proteome and its biological variations. In this study, we performed a comprehensive analysis of the human gastric fluid proteome using samples obtained from individuals with benign gastric conditions. Gastric fluid proteins were prefractionated using ultracentrifuge filters (3 kDa cutoff) and analyzed by two-dimensional gel electrophoresis (2-DE) and multidimensional LC-MS/MS. Our 2-DE analysis of 170 gastric fluid samples revealed distinct protein profiles for acidic and neutral samples, highlighting pH effects on protein composition. By 2D LC-MS/MS analysis of pooled samples, we identified 284 and 347 proteins in acidic and neutral samples respectively (FDR ≤1%), of which 265 proteins (72.4%) overlapped. However, unlike neutral samples, most proteins in acidic samples were identified from peptides in the filtrate (i.e., <3 kDa). Consistent with this finding, immunoblot analysis of six potential gastric cancer biomarkers rarely detected full-length proteins in acidic samples. These findings have important implications for biomarker studies because a majority of gastric cancer patients have neutral gastric fluid compared to noncancer controls. Consequently, sample stratification, choice of proteomic approaches, and validation strategy can profoundly affect the interpretation of biomarker findings. These observations should help to refine gastric fluid biomarker studies.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Jugo Gástrico/metabolismo , Perfilación de la Expresión Génica , Proteoma/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cromatografía Líquida de Alta Presión/métodos , Electroforesis en Gel Bidimensional , Endoscopía/métodos , Femenino , Regulación de la Expresión Génica , Humanos , Concentración de Iones de Hidrógeno , Immunoblotting/métodos , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
16.
J Food Sci ; 74(6): H162-7, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19723200

RESUMEN

Hyperthermal stress and resulting free radical generation is known to impair endurance capacity and immune cell redistribution during prolonged exercise. Caffeic acid phenethyl ester (CAPE), a phenolic compound purified from propolis, has many biological and pharmacological activities including antioxidation. To examine whether CAPE has protective effect against hyperthermal stress in athletes, we isolated peripheral blood mononuclear cells (MNC) from competitive cyclists and assessed their response to hyperthermia with or without CAPE pretreatment. We found that pretreatment of cyclists' MNC with CAPE (0, 1, 2, 4 microg/mL) reversed or reduced hyperthermia-induced survival inhibition, necrosis, superoxide production, glutathione depletion, and intracellular superoxide burst in a dose-dependent manner. These results suggest that CAPE may enhance the hyperthermal tolerance in immune mononuclear cells of competitive cyclists.


Asunto(s)
Antioxidantes/farmacología , Ácidos Cafeicos/farmacología , Calor/efectos adversos , Leucocitos Mononucleares/efectos de los fármacos , Alcohol Feniletílico/análogos & derivados , Aptitud Física/fisiología , Estrés Fisiológico/efectos de los fármacos , Ciclismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Prueba de Esfuerzo , Glutatión/análisis , Humanos , Técnicas In Vitro , Leucocitos Mononucleares/patología , Masculino , Necrosis/prevención & control , Alcohol Feniletílico/farmacología , Própolis/química , Superóxidos/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...