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1.
J Hepatol ; 81(1): 42-61, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38423478

RESUMO

BACKGROUND & AIMS: Hepatitis B surface antigen (HBsAg) loss or functional cure (FC) is considered the optimal therapeutic outcome for patients with chronic hepatitis B (CHB). However, the immune-pathological biomarkers and underlying mechanisms of FC remain unclear. In this study we comprehensively interrogate disease-associated cell states identified within intrahepatic tissue and matched PBMCs (peripheral blood mononuclear cells) from patients with CHB or after FC, at the resolution of single cells, to provide novel insights into putative mechanisms underlying FC. METHODS: We combined single-cell transcriptomics (single-cell RNA sequencing) with multiparametric flow cytometry-based immune phenotyping, and multiplexed immunofluorescence to elucidate the immunopathological cell states associated with CHB vs. FC. RESULTS: We found that the intrahepatic environment in CHB and FC displays specific cell identities and molecular signatures that are distinct from those found in matched PBMCs. FC is associated with the emergence of an altered adaptive immune response marked by CD4 cytotoxic T lymphocytes, and an activated innate response represented by liver-resident natural killer cells, specific Kupffer cell subtypes and marginated neutrophils. Surprisingly, we found MHC class II-expressing hepatocytes in patients achieving FC, as well as low but persistent levels of covalently closed circular DNA and pregenomic RNA, which may play an important role in FC. CONCLUSIONS: Our study provides conceptually novel insights into the immuno-pathological control of HBV cure, and opens exciting new avenues for clinical management, biomarker discovery and therapeutic development. We believe that the discoveries from this study, as it relates to the activation of an innate and altered immune response that may facilitate sustained, low-grade inflammation, may have broader implications in the resolution of chronic viral hepatitis. IMPACT AND IMPLICATIONS: This study dissects the immuno-pathological cell states associated with functionally cured chronic hepatitis B (defined by the loss of HBV surface antigen or HBsAg). We identified the sustained presence of very low viral load, accessory antigen-presenting hepatocytes, adaptive-memory-like natural killer cells, and the emergence of helper CD4 T cells with cytotoxic or effector-like signatures associated with functional cure, suggesting previously unsuspected alterations in the adaptive immune response, as well as a key role for the innate immune response in achieving or maintaining functional cure. Overall, the insights generated from this study may provide new avenues for the development of alternative therapies as well as patient surveillance for better clinical management of chronic hepatitis B.


Assuntos
Imunidade Adaptativa , Hepatite B Crônica , Imunidade Inata , Análise de Célula Única , Humanos , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Imunidade Inata/imunologia , Imunidade Adaptativa/imunologia , Análise de Célula Única/métodos , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/genética , Masculino , Feminino , Linfócitos T Citotóxicos/imunologia , Adulto , Fígado/imunologia , Fígado/patologia , Antígenos de Superfície da Hepatite B/imunologia , Pessoa de Meia-Idade , Células Matadoras Naturais/imunologia
2.
Sci Rep ; 11(1): 7455, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33811250

RESUMO

Our objective was to examine differences in cytokine/chemokine response in chronic hepatitis B(CHB) patients to understand the immune mechanism of HBsAg loss (functional cure) during antiviral therapy. We used an unbiased machine learning strategy to unravel the immune pathways in CHB nucleo(t)side analogue-treated patients who achieved HBsAg loss with peg-interferon-α(peg-IFN-α) add-on or switch treatment in a randomised clinical trial. Cytokines/chemokines from plasma were compared between those with/without HBsAg loss, at baseline, before and after HBsAg loss. Peg-IFN-α treatment resulted in higher levels of IL-27, IL-12p70, IL-18, IL-13, IL-4, IL-22 and GM-CSF prior to HBsAg loss. Probabilistic network analysis of cytokines, chemokines and soluble factors suggested a dynamic dendritic cell driven NK and T cell immune response associated with HBsAg loss. Bayesian network analysis showed a dominant myeloid-driven type 1 inflammatory response with a MIG and I-TAC central module contributing to HBsAg loss in the add-on arm. In the switch arm, HBsAg loss was associated with a T cell activation module exemplified by high levels of CD40L suggesting T cell activation. Our findings show that more than one immune pathway to HBsAg loss was found with peg-IFN-α therapy; by myeloid-driven Type 1 response in one instance, and T cell activation in the other.


Assuntos
Quimiocinas/sangue , Citocinas/sangue , Antígenos de Superfície da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Teorema de Bayes , Hepatite B Crônica/sangue , Humanos , Interferon-alfa/uso terapêutico , Fatores de Tempo
3.
Mol Ther ; 29(2): 734-743, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33038324

RESUMO

Advanced, late-stage Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma (NPC) is incurable, and its treatment remains a clinical and therapeutic challenge. Results from a phase II clinical trial in advanced NPC patients employing a combined chemotherapy and EBV-specific T cell (EBVST) immunotherapy regimen showed a response rate of 71.4%. Longitudinal analysis of patient samples showed that an increase in EBV DNA plasma concentrations and the peripheral monocyte-to-lymphocyte ratio negatively correlated with overall survival. These parameters were combined into a multivariate analysis to stratify patients according to risk of death. Immunophenotyping at serial time points showed that low-risk individuals displayed significantly decreased amounts of monocytic myeloid-derived suppressor cells postchemotherapy, which subsequently influenced successful cytotoxic T-lymphocyte (CTL) immunotherapy. Examination of the low-risk group, 2 weeks post-EBVST infusion, showed that individuals with a greater overall survival possessed an increased frequency of CD8 central and effector memory T cells, together with higher levels of plasma interferon (IFN)-γ, and cytotoxic lymphocyte-associated transcripts. These results highlight the importance of the rational selection of chemotherapeutic agents and consideration of their impact on both systemic immune responses and downstream cellular immunotherapy outcomes.


Assuntos
Imunoterapia Adotiva , Células Supressoras Mieloides/imunologia , Carcinoma Nasofaríngeo/imunologia , Carcinoma Nasofaríngeo/terapia , Linfócitos T/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Humanos , Imunoterapia Adotiva/métodos , Células Supressoras Mieloides/metabolismo , Carcinoma Nasofaríngeo/patologia , Linfócitos T/metabolismo , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Falha de Tratamento , Resultado do Tratamento
4.
Am J Respir Crit Care Med ; 199(7): 842-853, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30265843

RESUMO

RATIONALE: Allergic sensitization is associated with poor clinical outcomes in asthma, chronic obstructive pulmonary disease, and cystic fibrosis; however, its presence, frequency, and clinical significance in non-cystic fibrosis bronchiectasis remain unclear. OBJECTIVES: To determine the frequency and geographic variability that exists in a sensitization pattern to common and specific allergens, including house dust mite and fungi, and to correlate such patterns to airway immune-inflammatory status and clinical outcomes in bronchiectasis. METHODS: Patients with bronchiectasis were recruited in Asia (Singapore and Malaysia) and the United Kingdom (Scotland) (n = 238), forming the Cohort of Asian and Matched European Bronchiectasis, which matched recruited patients on age, sex, and bronchiectasis severity. Specific IgE response against a range of common allergens was determined, combined with airway immune-inflammatory status and correlated to clinical outcomes. Clinically relevant patient clusters, based on sensitization pattern and airway immune profiles ("immunoallertypes"), were determined. MEASUREMENTS AND MAIN RESULTS: A high frequency of sensitization to multiple allergens was detected in bronchiectasis, exceeding that in a comparator cohort with allergic rhinitis (n = 149). Sensitization was associated with poor clinical outcomes, including decreased pulmonary function and more severe disease. "Sensitized bronchiectasis" was classified into two immunoallertypes: one fungal driven and proinflammatory, the other house dust mite driven and chemokine dominant, with the former demonstrating poorer clinical outcome. CONCLUSIONS: Allergic sensitization occurs at high frequency in patients with bronchiectasis recruited from different global centers. Improving endophenotyping of sensitized bronchiectasis, a clinically significant state, and a "treatable trait" permits therapeutic intervention in appropriate patients, and may allow improved stratification in future bronchiectasis research and clinical trials.


Assuntos
Alérgenos/efeitos adversos , Alérgenos/imunologia , Aspergillus , Asma/etiologia , Asma/imunologia , Bronquiectasia/complicações , Bronquiectasia/imunologia , Pyroglyphidae , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Coortes , Feminino , Humanos , Hipersensibilidade/imunologia , Imunização , Masculino , Pessoa de Meia-Idade
5.
J Biol Chem ; 293(49): 18864-18878, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30291141

RESUMO

The inflammasome is a critical molecular complex that activates interleukin-1 driven inflammation in response to pathogen- and danger-associated signals. Germline mutations in the inflammasome sensor NLRP1 cause Mendelian systemic autoimmunity and skin cancer susceptibility, but its endogenous regulation remains less understood. Here we use a proteomics screen to uncover dipeptidyl dipeptidase DPP9 as a novel interacting partner with human NLRP1 and a related inflammasome regulator, CARD8. DPP9 functions as an endogenous inhibitor of NLRP1 inflammasome in diverse primary cell types from human and mice. DPP8/9 inhibition via small molecule drugs and CRISPR/Cas9-mediated genetic deletion specifically activate the human NLRP1 inflammasome, leading to ASC speck formation, pyroptotic cell death, and secretion of cleaved interleukin-1ß. Mechanistically, DPP9 interacts with a unique autoproteolytic domain (Function to Find Domain (FIIND)) found in NLRP1 and CARD8. This scaffolding function of DPP9 and its catalytic activity act synergistically to maintain NLRP1 in its inactive state and repress downstream inflammasome activation. We further identified a single patient-derived germline missense mutation in the NLRP1 FIIND domain that abrogates DPP9 binding, leading to inflammasome hyperactivation seen in the Mendelian autoinflammatory disease Autoinflammation with Arthritis and Dyskeratosis. These results unite recent findings on the regulation of murine Nlrp1b by Dpp8/9 and uncover a new regulatory mechanism for the NLRP1 inflammasome in primary human cells. Our results further suggest that DPP9 could be a multifunctional inflammasome regulator involved in human autoinflammatory diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Inflamassomos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Ácidos Borônicos/farmacologia , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Dipeptídeos/farmacologia , Dipeptidil Peptidases e Tripeptidil Peptidases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Mutação em Linhagem Germinativa , Células HEK293 , Humanos , Inflamação/genética , Mutação de Sentido Incorreto , Proteínas NLR , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Domínios Proteicos
6.
Data Brief ; 19: 1570-1573, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30246075

RESUMO

In this report the data was obtained from a prospective case-control study with a sample size of sixteen patients with exudative age related macular degeneration (AMD) due to choroidal neovascularization (CNV) and eighteen patients with polypoidal choroidal vasculopathy (PCV) and fifty controls (cataract patients without any other ocular diseases). Luminex bead based multiplex assay with a panel of 41 analytes was used to study the cytokine levels in plasma and aqueous humor.

7.
J Vis Exp ; (128)2017 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-29053687

RESUMO

Tear film is a complex mixture of lipids, proteins and minerals which covers the external surface of the eye, thereby providing lubrication, nutrition and protection to the underlying cells. Analysis of tears is an emerging area for the identification of biomarkers for the prediction, diagnosis, and prognosis of various ocular diseases. Tears are easily accessible and their collection is non-invasive. Therefore, advancing technologies are gaining prominence for identification of multiple analytes in tears to study changes in protein or metabolite composition and its association with pathological conditions. Tear cytokines are ideal biomarkers for studying the health of the ocular surface and also help in understanding the mechanisms of different ocular surface disorders like dry eye disease and vernal conjunctivitis. Bead based multiplex assays have the capability of detecting multiple analytes in a small amount of sample with a higher sensitivity. Here we describe a standardized protocol of tear sample collection, extraction and analysis of cytokine profiling using a bead based multiplex assay.


Assuntos
Bioensaio/métodos , Citocinas/metabolismo , Síndromes do Olho Seco/diagnóstico , Lágrimas/química , Humanos , Masculino , Padrões de Referência
8.
Data Brief ; 11: 152-154, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28224132

RESUMO

The data presented in this article shows the longitudinal analysis of tear fluid cytokine profiles, blood CD4 and CD8 counts and HIV viral load in 34 dry eye patients with HIV infection during the HAART therapy. Clinical samples were collected from HIV patients with dry eye disease at the time of presentation to the clinic (visit 1), three months (visit 2) and 6 months (visit 3) after the presentation. At each time point tear samples were evaluated for 41 cytokines using Luminex bead based multiplex assay and blood samples were tested for HIV viral load and CD4 and CD8 counts.

9.
Data Brief ; 10: 14-16, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27942559

RESUMO

The tear film cytokine profiling data in this article was obtained from a prospective case-control study with a sample size of 34 dry eye disease (DED) patients with HIV infection and 32 DED patients without HIV infection, see "A distinct cytokines profile in tear film of dry eye disease (DED) patients with HIV infection" (R. Agrawal, P.K. Balne, A. Veerappan, V.B. Au, B. Lee, E. Loo, A. Ghosh, L. Tong, S.C. Teoh, J. Connolly, P. Tan, 2016) [1]. Tear samples were collected from all the subjects using Schirmer׳s strips and cytokine profiling was done using the Luminex bead based multiplex assay with a panel of 41 analytes. The cytokine level differences in each group of subjects were analyzed using logistic regression models.

10.
Cytokine ; 88: 77-84, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27585367

RESUMO

PURPOSE: To investigate the tear cytokine profile in HIV patients with dry eye disease (DED) and study the association between the severity of ocular inflammatory complications and tear cytokines levels. We postulate that HIV-mediated inflammation may be the underlying pathogenic mechanism for HIV-associated DED. METHODS: The current prospective case-control study compared tear film cytokine profiles in DED patients with HIV infection (n=34) and age/gender-matched DED patients without HIV infection [controls (n=32)]. Participants were recruited from tertiary referral eye care centre and communicable disease clinics, Singapore. Ocular surface health was documented using tear film, Schirmer's test, corneal staining, and conjunctival injection measurements. Tear samples were collected using Schirmer's strips and analysed for the levels of 41 cytokines using Luminex bead assay. Logistic regression models were performed to determine correlation and significance. RESULTS: Among the 41 cytokines analysed, statistically significant differences were observed in the mean values of epithelial growth factor (EGF), growth related oncogene (GRO) and interferon gamma-induced protein 10 (IP-10). EGF and IP-10 levels were higher and GRO levels were lower in the tears of DED patients with HIV infection compared to DED patients without HIV infection. No significant association was found between varying levels of ocular surface parameters and cytokine concentrations in HIV patients with DED (p>0.05). CONCLUSIONS: EGF and IP-10 were significantly elevated and GRO levels were lower in the tear profile of HIV patients with DED compared to immunocompetent patients with DED. This study suggests a novel cytokine driven paradigm for ocular inflammatory complications of HIV infection. Additional studies in large organised cohorts can validate the results.


Assuntos
Citocinas/metabolismo , Síndromes do Olho Seco/metabolismo , Infecções por HIV/metabolismo , HIV-1 , Lágrimas/metabolismo , Adulto , Síndromes do Olho Seco/etiologia , Feminino , Infecções por HIV/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Data Brief ; 8: 1232-42, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27547803

RESUMO

The data shows the aqueous humor cytokine profiling results acquired in a small cohort of 17 HIV patients clinically diagnosed with Cytomegalovirus retinitis using the FlexMAP 3D (Luminex®) platform using the Milliplex Human Cytokine® kit. Aqueous humor samples were collected from these patients at different time points (pre-treatment and at 4-weekly intervals through the 12-week course of intravitreal ganciclovir treatment) and 41 cytokine levels were analyzed at each time point. CMV DNA viral load was assessed in 8 patients at different time points throughout the course of ganciclovir treatment. The data described herein is related to the research article entitled "Aqueous humor immune factors and cytomegalovirus (CMV) levels in CMV retinitis through treatment - The CRIGSS study" (Iyer et al., 2016) [1]. Cytokine levels against the different time points which indicate the response to the given treatment and against the CMV viral load were analyzed.

12.
Cytokine ; 84: 56-62, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27239802

RESUMO

PURPOSE: This study aims to perform comprehensive longitudinal immune factor analysis of aqueous humor in relation to the aqueous CMV viral load and systemic CD4 counts during treatment of patients with co-infection of HIV and CMVR. METHODS: Aqueous humor samples were collected from 17 HIV-positive patients with CMVR scheduled to undergo weekly intravitreal ganciclovir therapy as part of the prospective CMV Retinitis Intravitreal Ganciclovir Singapore Study (CRIGSS) over the course of 1year. Full data across all the 4 time points was obtained and analyzed for CMV DNA viral load, 41 cytokine and chemokine factors using real-time PCR with the FlexMAP 3D (Luminex®) platform and assessed using the Milliplex Human Cytokine® kit. RESULTS: The following immune factors (Spearman correlation coefficient r value in parenthesis, p<0.05) showed strong correlation with CMV DNA load in the aqueous - MCP-1 (0.80, IFN-g (0.83), IP-10 (0.82), IL-8 (0.81), fractalkine (0.73), RANTES (0.68) - while the following showed moderate correlation - PDGF-AA (0.58), Flt-3L (0.59) and G-CSF (0.53). Only PDGF-AA revealed a statistically significant negative correlation with serum CD4 levels (r=-0.74). CONCLUSION: Immune factors that correlate with intraocular CMV DNA load are identified. They are indicative of a Th1 and monocyte-macrophage mediated response, and exhibit a decreasing trend longitudinally through the course of treatment. These factors may be an important new consideration in individualizing the treatment of patients with CMVR.


Assuntos
Humor Aquoso/imunologia , Humor Aquoso/virologia , Retinite por Citomegalovirus/imunologia , Retinite por Citomegalovirus/virologia , Fatores Imunológicos/imunologia , Adulto , Antivirais/uso terapêutico , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Coinfecção/tratamento farmacológico , Coinfecção/imunologia , Coinfecção/virologia , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/imunologia , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Retinite por Citomegalovirus/tratamento farmacológico , Feminino , Ganciclovir/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/imunologia , HIV/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Interleucina-8/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Singapura
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