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1.
Nature ; 614(7947): 334-342, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36697826

RESUMO

The liver is bathed in bacterial products, including lipopolysaccharide transported from the intestinal portal vasculature, but maintains a state of tolerance that is exploited by persistent pathogens and tumours1-4. The cellular basis mediating this tolerance, yet allowing a switch to immunity or immunopathology, needs to be better understood for successful immunotherapy of liver diseases. Here we show that a variable proportion of CD8+ T cells compartmentalized in the human liver co-stain for CD14 and other prototypic myeloid membrane proteins and are enriched in close proximity to CD14high myeloid cells in hepatic zone 2. CD14+CD8+ T cells preferentially accumulate within the donor pool in liver allografts, among hepatic virus-specific and tumour-infiltrating responses, and in cirrhotic ascites. CD14+CD8+ T cells exhibit increased turnover, activation and constitutive immunomodulatory features with high homeostatic IL-10 and IL-2 production ex vivo, and enhanced antiviral/anti-tumour effector function after TCR engagement. This CD14+CD8+ T cell profile can be recapitulated by the acquisition of membrane proteins-including the lipopolysaccharide receptor complex-from mononuclear phagocytes, resulting in augmented tumour killing by TCR-redirected T cells in vitro. CD14+CD8+ T cells express integrins and chemokine receptors that favour interactions with the local stroma, which can promote their induction through CXCL12. Lipopolysaccharide can also increase the frequency of CD14+CD8+ T cells in vitro and in vivo, and skew their function towards the production of chemotactic and regenerative cytokines. Thus, bacterial products in the gut-liver axis and tissue stromal factors can tune liver immunity by driving myeloid instruction of CD8+ T cells with immunomodulatory ability.


Assuntos
Linfócitos T CD8-Positivos , Tolerância Imunológica , Receptores de Lipopolissacarídeos , Lipopolissacarídeos , Fígado , Células Mieloides , Humanos , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Células Mieloides/imunologia , Células Mieloides/metabolismo , Neoplasias/imunologia , Neoplasias/patologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/imunologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/patologia , Fígado/virologia , Interleucina-2/biossíntese , Interleucina-2/imunologia , Quimiotaxia de Leucócito , Bactérias/imunologia , Intestinos/imunologia , Intestinos/microbiologia
2.
Hepatology ; 79(5): 1129-1140, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870278

RESUMO

BACKGROUND AND AIMS: Studies have suggested that patients with chronic hepatitis B, either co- or superinfected, have more aggressive liver disease progression than those with the HDV. This systematic literature review and meta-analysis examined whether HDV RNA status is associated with increased risk of advanced liver disease events in patients who are HBsAg and HDV antibody positive. APPROACH AND RESULTS: A total of 12 publications were included. Relative rates of progression to advanced liver disease event for HDV RNA+/detectable versus HDV RNA-/undetectable were extracted for analysis. Reported OR and HRs with 95% CI were pooled using the Hartung-Knapp-Sidik-Jonkman method for random-effects models. The presence of HDV RNA+ was associated with an increased risk of any advanced liver disease event [random effect (95% CI): risk ratio: 1.48 (0.93, 2.33); HR: 2.62 (1.55, 4.44)]. When compared to the patients with HDV RNA- status, HDV RNA+ was associated with a significantly higher risk of progressing to compensated cirrhosis [risk ratio: 1.74 (1.24, 2.45)] decompensated cirrhosis [HR: 3.82 (1.60, 9.10)], HCC [HR: 2.97 (1.87, 4.70)], liver transplantation [HR: 7.07 (1.61, 30.99)], and liver-related mortality [HR: 3.78 (2.18, 6.56)]. CONCLUSIONS: The patients with HDV RNA+ status have a significantly greater risk of liver disease progression than the patients who are HDV RNA-. These findings highlight the need for improved HDV screening and linkage to treatment to reduce the risk of liver-related morbidity and mortality.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Vírus Delta da Hepatite/genética , Antígenos de Superfície da Hepatite B , Cirrose Hepática/complicações , Morbidade , RNA Viral , Progressão da Doença , Vírus da Hepatite B/genética
3.
Hepatology ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687604

RESUMO

BACKGROUND AND AIMS: HBV and HIV coinfection is a common occurrence globally, with significant morbidity and mortality. Both viruses lead to immune dysregulation including changes in natural killer (NK) cells, a key component of antiviral defense and a promising target for HBV cure strategies. Here we used high-throughput single-cell analysis to explore the immune cell landscape in people with HBV mono-infection and HIV/HBV coinfection, on antiviral therapy, with emphasis on identifying the distinctive characteristics of NK cell subsets that can be therapeutically harnessed. APPROACH AND RESULTS: Our data show striking differences in the transcriptional programs of NK cells. HIV/HBV coinfection was characterized by an over-representation of adaptive, KLRC2 -expressing NK cells, including a higher abundance of a chemokine-enriched ( CCL3/CCL4 ) adaptive cluster. The NK cell remodeling in HIV/HBV coinfection was reflected in enriched activation pathways, including CD3ζ phosphorylation and ZAP-70 translocation that can mediate stronger antibody-dependent cellular cytotoxicity responses and a bias toward chemokine/cytokine signaling. By contrast, HBV mono-infection imposed a stronger cytotoxic profile on NK cells and a more prominent signature of "exhaustion" with higher circulating levels of HBsAg. Phenotypic alterations in the NK cell pool in coinfection were consistent with increased "adaptiveness" and better capacity for antibody-dependent cellular cytotoxicity compared to HBV mono-infection. Overall, an adaptive NK cell signature correlated inversely with circulating levels of HBsAg and HBV-RNA in our cohort. CONCLUSIONS: This study provides new insights into the differential signature and functional profile of NK cells in HBV and HIV/HBV coinfection, highlighting pathways that can be manipulated to tailor NK cell-focused approaches to advance HBV cure strategies in different patient groups.

4.
Nature ; 574(7777): 200-205, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31582858

RESUMO

The responses of CD8+ T cells to hepatotropic viruses such as hepatitis B range from dysfunction to differentiation into effector cells, but the mechanisms that underlie these distinct outcomes remain poorly understood. Here we show that priming by Kupffer cells, which are not natural targets of hepatitis B, leads to differentiation of CD8+ T cells into effector cells that form dense, extravascular clusters of immotile cells scattered throughout the liver. By contrast, priming by hepatocytes, which are natural targets of hepatitis B, leads to local activation and proliferation of CD8+ T cells but not to differentiation into effector cells; these cells form loose, intravascular clusters of motile cells that coalesce around portal tracts. Transcriptomic and chromatin accessibility analyses reveal unique features of these dysfunctional CD8+ T cells, with limited overlap with those of exhausted or tolerant T cells; accordingly, CD8+ T cells primed by hepatocytes cannot be rescued by treatment with anti-PD-L1, but instead respond to IL-2. These findings suggest immunotherapeutic strategies against chronic hepatitis B infection.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Apresentação Cruzada/imunologia , Vírus da Hepatite B/imunologia , Hepatócitos/imunologia , Hepatócitos/virologia , Animais , Antígeno B7-H1/antagonistas & inibidores , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Cromatina/metabolismo , Feminino , Hepatite B/tratamento farmacológico , Hepatite B/imunologia , Hepatite B/virologia , Humanos , Tolerância Imunológica , Interleucina-2/imunologia , Interleucina-2/uso terapêutico , Células de Kupffer/imunologia , Ativação Linfocitária , Masculino , Camundongos , Transcriptoma/genética
5.
J Viral Hepat ; 31(1): 3-11, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37881873

RESUMO

Pregnant mothers with chronic hepatitis B infection (CHB) need peri-partum antiviral prophylaxis (PAP) to reduce the risk of mother-to-child-transmission. Currently, PAP is recommended in those with high viral load (VL) that is, HBV DNA >200,000 IU/mL. Quantitative hepatitis B surface antigen (qHBsAg) >10,000 IU/mL, a cut-off derived primarily from hepatitis B e-antigen (HBeAg) positive antenatal cohorts in Chinese populations, is advocated as a surrogate marker of VL for guiding PAP. We investigated the utility of qHBsAg to predict high-VL in a multi-ethnic urban cohort with CHB. A consecutive cohort of women with CHB was identified from Barts Health NHS Trust databases in the United Kingdom. We included women with paired HBV DNA and qHBsAg during pregnancy. Women already on antiviral at conception were excluded. A total of 769 pregnancies in 678 CHB pregnant mothers (median age 31 years-old, 8.6% HBeAg+) were included. At median gestational age of 15.3 weeks, HBV DNA was 336 (IQR 44-2998) IU/mL, with 65 (8.5%) being high-VL. Serum qHBsAg was most useful in Black/Black-British/Caribbean/African (AUROC 0.946) with 100% sensitivity and 80.6% specificity to predict high-VL; but it performed less well for other ethnicities: Asian (AUROC 0.877), White (AUROC 0.797) and mixed ethnicities (AUROC 0.742). In conclusion, for settings where healthcare resources are not limited, HBV DNA remains the optimal marker to identify highly viraemic pregnancies for guiding PAP. For resource-limited settings where the prevailing cost is treatment, serum qHBsAg can be used in Black/Black British/Caribbean/African sub-cohorts, but not for other ethnicities.


Assuntos
Hepatite B Crônica , Hepatite B , Feminino , Humanos , Gravidez , Adulto , Lactente , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , DNA Viral , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/prevenção & controle , Hepatite B/tratamento farmacológico , Antivirais/uso terapêutico
6.
J Viral Hepat ; 30 Suppl 1: 11-20, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36458851

RESUMO

Hepatitis D virus (HDV) causes one of the most severe forms of hepatitis in people with chronic hepatitis B (CHB) infection. Timely and accurate assessment of hepatitis delta virus (HDV) and disease stratification is mandatory for thorough pre-therapeutic evaluation for prioritizing treatment and outcome prediction. Viral biomarkers associated with HDV and hepatitis B virus (HBV) are crucial to aid in diagnosis, and monitoring of serum viral nucleic acids for both viruses is recommended. Liver biopsy remains the gold standard for staging of liver fibrosis and grading of histological activity and should remain central for diagnostic purposes, but is also of importance for research to enhance our understanding of HDV. The emergence of novel non-invasive tests for the assessment of liver fibrosis in HDV patients coupled with the well-recognized potential complications of liver biopsy has resulted in reduced utility of liver biopsy in clinical practice. Preliminary data suggest that these emerging non-invasive modalities appear to be reliable, and their use is supported, similar to other viral hepatitis. Nevertheless, further validation is required before their widespread adoption into clinical practice.


Assuntos
Hepatite B , Hepatite D , Humanos , Vírus Delta da Hepatite , Vírus da Hepatite B , Cirrose Hepática/diagnóstico , Hepatite D/diagnóstico
7.
Gut ; 71(7): 1399-1411, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34548339

RESUMO

OBJECTIVE: Tissue-resident memory T cells (TRM) are vital immune sentinels that provide protective immunity. While hepatic CD8+ TRM have been well described, little is known about the location, phenotype and function of CD4+ TRM. DESIGN: We used multiparametric flow cytometry, histological assessment and novel human tissue coculture systems to interrogate the ex vivo phenotype, function and generation of the intrahepatic CD4+ T-cell compartment. We also used leukocytes isolated from human leukocyte antigen (HLA)-disparate liver allografts to assess long-term retention. RESULTS: Hepatic CD4+ T cells were delineated into three distinct populations based on CD69 expression: CD69-, CD69INT and CD69HI. CD69HICD4+ cells were identified as tissue-resident CD4+ T cells on the basis of their exclusion from the circulation, phenotypical profile (CXCR6+CD49a+S1PR1-PD-1+) and long-term persistence within the pool of donor-derived leukcoocytes in HLA-disparate liver allografts. CD69HICD4+ T cells produced robust type 1 polyfunctional cytokine responses on stimulation. Conversely, CD69INTCD4+ T cells represented a more heterogenous population containing cells with a more activated phenotype, a distinct chemokine receptor profile (CX3CR1+CXCR3+CXCR1+) and a bias towards interleukin-4 production. While CD69INTCD4+ T cells could be found in the circulation and lymph nodes, these cells also formed part of the long-term resident pool, persisting in HLA-mismatched allografts. Notably, frequencies of CD69INTCD4+ T cells correlated with necroinflammatory scores in chronic hepatitis B infection. Finally, we demonstrated that interaction with hepatic epithelia was sufficient to generate CD69INTCD4+ T cells, while additional signals from the liver microenvironment were required to generate liver-resident CD69HICD4+ T cells. CONCLUSIONS: High and intermediate CD69 expressions mark human hepatic CD4+ TRM and a novel functionally distinct recirculating population, respectively, both shaped by the liver microenvironment to achieve diverse immunosurveillance.


Assuntos
Linfócitos T CD4-Positivos , Fígado , Linfócitos T CD8-Positivos , Citocinas/imunologia , Humanos , Memória Imunológica , Fígado/imunologia , Monitorização Imunológica
8.
Gut ; 70(12): 2337-2348, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33402415

RESUMO

OBJECTIVE: The involvement of HBV DNA integration in promoting hepatocarcinogenesis and the extent to which the intrahepatic HBV reservoir modulates liver disease progression remains poorly understood. We examined the intrahepatic HBV reservoir, the occurrence of HBV DNA integration and its impact on the hepatocyte transcriptome in hepatitis B 'e' antigen (HBeAg)-negative chronic hepatitis B (CHB). DESIGN: Liver tissue from 84 HBeAg-negative patients with CHB with low (n=12), moderate (n=25) and high (n=47) serum HBV DNA was analysed. Covalently closed circular DNA (cccDNA), pregenomic RNA (pgRNA) were evaluated by quantitative PCR, whole exome and transcriptome sequencing was performed by Illumina, and the burden of HBV DNA integrations was evaluated by digital droplet PCR. RESULTS: Patients with low and moderate serum HBV DNA displayed comparable intrahepatic cccDNA and pgRNA, significantly lower than in patients with high HBV DNA, while hepatitis B core-related antigen correlated strongly with the intrahepatic HBV reservoir, reflecting cccDNA quantity. Whole exome integration was detected in a significant number of patients (55.6%, 14.3% and 25% in high, moderate and low viraemic patients, respectively), at a frequency ranging from 0.5 to 157 integrations/1000 hepatocytes. Hepatitis B surface antigen >5000 IU/mL predicted integration within the exome and these integrations localised in genes involved in hepatocarcinogenesis, regulation of lipid/drug metabolism and antiviral/inflammatory responses. Transcript levels of specific genes, including the proto-oncogene hRAS, were higher in patients with HBV DNA integration, supporting an underlying oncogenic risk in patients with low-level to moderate-level viraemia. CONCLUSIONS: HBV DNA integration occurs across all HBeAg-negative patients with CHB, including those with a limited HBV reservoir; localising in genes involved in carcinogenesis and altering the hepatocyte transcriptome.


Assuntos
DNA Viral/sangue , DNA Viral/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/genética , Hepatócitos/virologia , Adulto , Biomarcadores/sangue , Feminino , Genótipo , Antígenos E da Hepatite B/sangue , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Transcriptoma , Viremia , Sequenciamento do Exoma
9.
Gastroenterology ; 159(2): 652-664, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32302614

RESUMO

BACKGROUND & AIMS: Chronic hepatitis B virus (HBV) infection is characterized by the presence of defective viral envelope proteins (hepatitis B surface antigen [HBsAg]) and the duration of infection-most patients acquire the infection at birth or during the first years of life. We investigated the effects of these factors on patients' lymphocyte and HBV-specific T-cell populations. METHODS: We collected blood samples and clinical data from 243 patients with HBV infection (3-75 years old) in the United Kingdom and China. We measured levels of HBV DNA, HBsAg, hepatitis B e antigen, and alanine aminotransferase; analyzed HBV genotypes; and isolated peripheral blood mononuclear cells (PBMCs). In PBMCs from 48 patients with varying levels of serum HBsAg, we measured 40 markers on nature killer and T cells by mass cytometry. PBMCs from 189 patients with chronic infection and 38 patients with resolved infections were incubated with HBV peptide libraries, and HBV-specific T cells were identified by interferon gamma enzyme-linked immune absorbent spot (ELISpot) assays or flow cytometry. We used multivariate linear regression and performed variable selection using the Akaike information criterion to identify covariates associated with HBV-specific responses of T cells. RESULTS: Although T- and natural killer cell phenotypes and functions did not change with level of serum HBsAg, numbers of HBs-specific T cells correlated with serum levels of HBsAg (r = 0.3367; P < .00001). After we performed the variable selection, the multivariate linear regression model identified patient age as the only factor significantly associated with numbers of HBs-specific T cells (P = .000115). In patients younger than 30 years, HBs-specific T cells constituted 28.26% of the total HBV-specific T cells; this value decreased to 7.14% in patients older than 30 years. CONCLUSIONS: In an analysis of immune cells from patients with chronic HBV infection, we found that the duration of HBsAg exposure, rather than the quantity of HBsAg, was associated with the level of anti-HBV immune response. Although the presence of HBs-specific T cells might not be required for the clearance of HBV infection in all patients, strategies to restore anti-HBV immune responses should be considered in patients younger than 30 years.


Assuntos
Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Fatores Etários , Antivirais/uso terapêutico , Células Cultivadas , Criança , Pré-Escolar , DNA Viral/isolamento & purificação , Feminino , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/sangue , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Humanos , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Fatores de Tempo , Adulto Jovem
10.
J Viral Hepat ; 28(7): 976-981, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33665937

RESUMO

Hepatitis B virus (HBV) is a highly infectious bloodborne virus, which remains endemic in large geographic areas and represents a major global healthcare challenge. HBV transmission from healthcare workers, who perform exposure prone procedures (EPP), to patients is a recognized transmission risk, which varies widely globally. Although the risk is small in developed countries, it increases significantly in high-prevalent, low-resource countries, representing a major challenge to these healthcare systems and underlining the necessity for robust guidance to be in place. The HBV landscape has evolved as a result of global vaccination programs, implementation of standard precautions and the advent of new generation antiviral agents (3rd generation nucleos(t)ide analogues). In light of the progress in the field, the UK Advisory Panel for Healthcare Workers Infected with Bloodborne Viruses (UKAP) recently issued updated guidance, which essentially removes past barriers, restricting healthcare workers from performing EPPs solely on the basis of HBV DNA level, regardless of hepatitis B 'e' antigen and/or treatment status. Although the current recommendations remain conservative compared to those of other developed healthcare systems, UK practice is now in line with other high-income countries, while ensuring patient safety remains paramount, without unduly restricting HCWs from clinical practice. The current article presents the latest UKAP guidance, considers its implications for HCWs and compares it with the guidance from major international scientific societies and governing bodies.


Assuntos
Hepatite B Crônica , Hepatite B , Saúde Ocupacional , Pessoal de Saúde , Vírus da Hepatite B , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/prevenção & controle , Humanos , Políticas , Reino Unido/epidemiologia
11.
Gut ; 68(8): 1493-1503, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30487267

RESUMO

OBJECTIVE: In order to refine new therapeutic strategies in the pipeline for HBV cure, evaluation of virological and immunological changes compartmentalised at the site of infection will be required. We therefore investigated if liver fine needle aspirates (FNAs) could comprehensively sample the local immune landscape in parallel with viable hepatocytes. DESIGN: Matched blood, liver biopsy and FNAs from 28 patients with HBV and 15 without viral infection were analysed using 16-colour multiparameter flow cytometry. RESULTS: The proportion of CD4 T, CD8 T, Mucosal Associated Invariant T cell (MAIT), Natural Killer (NK) and B cells identified by FNA correlated with that in liver biopsies from the same donors. Populations of Programmed Death-1 (PD-1)hiCD39hi tissue-resident memory CD8 T cells (CD69+CD103+) and liver-resident NK cells (CXCR6+T-betloEomeshi), were identified by both FNA and liver biopsy, and not seen in the blood. Crucially, HBV-specific T cells could be identified by FNAs at similar frequencies to biopsies and enriched compared with blood. FNAs could simultaneously identify populations of myeloid cells and live hepatocytes expressing albumin, Scavenger Receptor class B type 1 (SR-B1), Programmed Death-Ligand 1 (PD-L1), whereas hepatocytes were poorly viable after the processing required for liver biopsies. CONCLUSION: We demonstrate for the first time that FNAs identify a range of intrahepatic immune cells including locally resident sentinel HBV-specific T cells and NK cells, together with PD-L1-expressing hepatocytes. In addition, we provide a scoring tool to estimate the extent to which an individual FNA has reliably sampled intrahepatic populations rather than contaminating blood. The broad profiling achieved by this less invasive, rapid technique makes it suitable for longitudinal monitoring of the liver to optimise new therapies for HBV.


Assuntos
Biópsia por Agulha Fina/métodos , Hepatite B Crônica , Hepatócitos , Adulto , Algoritmos , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , DNA Viral/sangue , Feminino , Citometria de Fluxo/métodos , Vírus da Hepatite B/genética , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Hepatócitos/imunologia , Hepatócitos/patologia , Humanos , Células Matadoras Naturais/imunologia , Masculino , Receptor de Morte Celular Programada 1/imunologia , Reprodutibilidade dos Testes , Receptores Depuradores Classe B/imunologia
12.
J Viral Hepat ; 26(1): 4-15, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30415490

RESUMO

Despite the availability of a preventative vaccine, chronic hepatitis B (CHB) remains a global healthcare challenge with the risk of disease progression due to cirrhosis and hepatocellular carcinoma. Although current treatment strategies, interferon and nucleos(t)ide analogues have contributed to reducing morbidity and mortality related to CHB, these therapies are limited in providing functional cure. The treatment paradigm in CHB is rapidly evolving with a number of new agents in the developmental pipeline. However, until novel agents with functional cure capability are available in the clinical setting, there is a pressing need to optimize currently licensed therapies. Here, we discuss current agents used alone and/or in combination strategies along with the impact of these therapies on viral and immune responses. Novel treatment strategies are outlined, and the potential role of current therapies in the employment of pipeline agents is discussed.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Avaliação de Medicamentos/legislação & jurisprudência , Avaliação de Medicamentos/métodos , Avaliação de Medicamentos/tendências , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica/complicações , Humanos , Interferons/uso terapêutico , Nucleosídeos/uso terapêutico
13.
Mol Ther ; 26(11): 2553-2566, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30217730

RESUMO

Checkpoint inhibitors and adoptive cell therapy provide promising options for treating solid cancers such as HBV-related HCC, but they have limitations. We tested the potential to combine advantages of each approach, genetically reprogramming T cells specific for viral tumor antigens to overcome exhaustion by down-modulating the co-inhibitory receptor PD-1. We developed a novel lentiviral transduction protocol to achieve preferential targeting of endogenous or TCR-redirected, antigen-specific CD8 T cells for shRNA knockdown of PD-1 and tested functional consequences for antitumor immunity. Antigen-specific and intrahepatic CD8 T cells transduced with lentiviral (LV)-shPD-1 consistently had a marked reduction in PD-1 compared to those transduced with a control lentiviral vector. PD-1 knockdown of human T cells rescued antitumor effector function and promoted killing of hepatoma cells in a 3D microdevice recapitulating the pro-inflammatory PD-L1hi liver microenvironment. However, upon repetitive stimulation, PD-1 knockdown drove T cell senescence and induction of other co-inhibitory pathways. We provide the proof of principle that T cells with endogenous or genetically engineered specificity for HBV-associated HCC viral antigens can be targeted for functional genetic editing. We show that PD-1 knockdown enhances immediate tumor killing but is limited by compensatory engagement of alternative co-inhibitory and senescence program upon repetitive stimulation.


Assuntos
Carcinoma Hepatocelular/terapia , Hepatite B Crônica/terapia , Neoplasias Hepáticas/terapia , Receptor de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T/uso terapêutico , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/uso terapêutico , Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Vetores Genéticos/genética , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Imunoterapia Adotiva/métodos , Lentivirus/genética , Fígado/imunologia , Fígado/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/uso terapêutico , Receptores de Antígenos de Linfócitos T/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
14.
Gut ; 67(4): 767-775, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29331944

RESUMO

In order to optimally refine the multiple emerging drug targets for hepatitis B virus (HBV), it is vital to evaluate virological and immunological changes at the site of infection. Traditionally liver biopsy has been the mainstay of HBV disease assessment, but with the emergence of non-invasive markers of liver fibrosis, there has been a move away from tissue sampling. Here we argue that liver biopsy remains an important tool, not only for the clinical assessment of HBV but also for research progress and evaluation of novel agents. The importance of liver sampling has been underscored by recent findings of specialised subsets of tissue-resident immune subsets capable of efficient pathogen surveillance, compartmentalised in the liver and not sampled in the blood. Importantly, the assessment of virological parameters, such as cccDNA quantitation, also requires access to liver tissue. We discuss strategies to maximise information obtained from the site of infection and disease pathology. Fine needle aspirates of the liver may allow longitudinal sampling of the local virus/host landscape. The careful utilisation of liver tissue and aspirates in conjunction with blood will provide critical information in the assessment of new therapeutics for the functional cure of HBV.


Assuntos
Biópsia por Agulha Fina/métodos , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/patologia , Antivirais/uso terapêutico , DNA Viral/sangue , Hepatite B Crônica/tratamento farmacológico , Humanos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Replicação Viral/efeitos dos fármacos
15.
PLoS Pathog ; 12(8): e1005788, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27487232

RESUMO

NK cells are important antiviral effectors, highly enriched in the liver, with the potential to regulate immunopathogenesis in persistent viral infections. Here we examined whether changes in the NK pool are induced when patients with eAg-positive CHB are 'primed' with PegIFNα and importantly, whether these changes are sustained or further modulated long-term after switching to nucleos(t)ides (sequential NUC therapy), an approach currently tested in the clinic. Longitudinal sampling of a prospectively recruited cohort of patients with eAg+CHB showed that the cumulative expansion of CD56bright NK cells driven by 48-weeks of PegIFNα was maintained at higher than baseline levels throughout the subsequent 9 months of sequential NUCs. Unexpectedly, PegIFNα-expanded NK cells showed further augmentation in their expression of the activating NK cell receptors NKp30 and NKp46 during sequential NUCs. The expansion in proliferating, functional NK cells was more pronounced following sequential NUCs than in comparison cohorts of patients treated with de novo NUCs or PegIFNα only. Reduction in circulating HBsAg concentrations, a key goal in the path towards functional cure of CHB, was only achieved in those patients with enhancement of NK cell IFNγ and cytotoxicity but decrease in their expression of the death ligand TRAIL. In summary, we conclude that PegIFNα priming can expand a population of functional NK cells with an altered responsiveness to subsequent antiviral suppression by NUCs. Patients on sequential NUCs with a distinct NK cell profile show a decline in HBsAg, providing mechanistic insights for the further optimisation of treatment strategies to achieve sustained responses in CHB.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B/tratamento farmacológico , Interferon-alfa/administração & dosagem , Células Matadoras Naturais/imunologia , Carga Viral/imunologia , Feminino , Hepatite B/imunologia , Hepatite B/patologia , Antígenos de Superfície da Hepatite B/imunologia , Humanos , Células Matadoras Naturais/patologia , Masculino , Receptor 1 Desencadeador da Citotoxicidade Natural/imunologia , Receptor 3 Desencadeador da Citotoxicidade Natural/imunologia , Estudos Prospectivos
17.
Gastroenterology ; 151(5): 986-998.e4, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27453547

RESUMO

BACKGROUND & AIMS: Chronic infection with hepatitis B virus (HBV) progresses through different phases. The first, called the immune-tolerant phase, has been associated with a lack of disease activity. We examined HBV-DNA integration, clonal hepatocyte expansion, HBV antigen expression, and HBV-specific immune responses in patients in the immune-tolerant phase to assess whether this designation is appropriate or if there is evidence of disease activity. METHODS: We studied HBV-DNA integration, clonal hepatocyte expansion, and expression of hepatitis B surface antigen and core antigen in liver tissues from 26 patients with chronic HBV infection (ages, 14-39 y); 9 patients were positive for hepatitis B e antigen (HBeAg) in the immune-tolerant phase and were matched for age with 10 HBeAg-positive patients with active disease and 7 HBeAg-negative patients with active disease. Peripheral blood samples were collected and HBV-specific T cells were quantified for each group. RESULTS: Detection of HBV antigens differed among groups. However, unexpectedly high numbers of HBV-DNA integrations, randomly distributed among chromosomes, were detected in all groups. Clonal hepatocyte expansion in patients considered immune tolerant also was greater than expected, potentially in response to hepatocyte turnover mediated by HBV-specific T cells, which were detected in peripheral blood cells from patients in all phases of infection. CONCLUSIONS: We measured HBV-specific T cells, HBV-DNA integration, and clonal hepatocyte expansion in different disease phases of young patients with chronic hepatitis B, with emphasis on the so-called immune-tolerant phase. A high level of HBV-DNA integration and clonal hepatocyte expansion in patients considered immune tolerant indicated that hepatocarcinogenesis could be underway-even in patients with early stage chronic HBV infection. Our findings do not support the concepts that this phase is devoid of markers of disease progression or that an immune response has not been initiated. We propose that this early phase be called a high-replication, low-inflammation stage. The timing of therapeutic interventions to minimize further genetic damage to the hepatocyte population should be reconsidered.


Assuntos
Antígenos de Superfície da Hepatite B/metabolismo , Antígenos E da Hepatite B/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/virologia , Hepatócitos/virologia , Tolerância Imunológica , Integração Viral/imunologia , Adolescente , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , DNA Viral/imunologia , Feminino , Vírus da Hepatite B/genética , Hepatite B Crônica/imunologia , Hepatócitos/imunologia , Humanos , Masculino , Análise por Pareamento , Adulto Jovem
18.
Med Microbiol Immunol ; 206(4): 295-299, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28401351

RESUMO

Intrahepatic total HBV DNA (it-HBV DNA) level might reflect the size of virus reservoir and correlate with the histological status of the liver. To quantitate it-HBV DNA in a series of 70 liver biopsies obtained from hepatitis B chronic patients, a modified version of the COBAS®Ampliprep/COBAS®TaqMan HBV test v2.0 was used for this purpose. The linearity and reproducibility of the modified protocol was tested by quantifying serial dilutions of a full-length HBV containing plasmid and it-HBV DNA from a reference patient. A good linear trend between the expected values and those generated by the assay was observed at different concentrations of both plasmid and reference patient (R 2 = 0.994 and 0.962, respectively). Differences between the values obtained in two independent runs were ≤0.3 log IU for the plasmid and ≤0.6 log IU/mg for the reference patient, showing a high inter-run reproducibility. In the 70 liver biopsies, it-HBV DNA level ranged from 1.4 to 5.4 log IU/mg, with a good linearity and reproducibility between the values obtained in two runs [R 2 = 0.981; median (IQR) difference of it-HBV DNA 0.05 (0.02-0.09) IU/mg]. The modified COBAS®Ampliprep/COBAS®TaqMan HBV test v2.0 allows an accurate quantitation of it-HBV DNA. Its determination may have prognostic value and may be a useful tool for the new therapeutic strategies aimed at eradicating the HBV infection.


Assuntos
DNA Viral/análise , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Fígado/virologia , Carga Viral/métodos , Adulto , Biópsia , Feminino , Vírus da Hepatite B/genética , Humanos , Masculino , Reprodutibilidade dos Testes
19.
J Infect Dis ; 211(3): 374-82, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25156561

RESUMO

BACKGROUND: Tenofovir disoproxil fumarate (TDF) is an established nucleotide analogue in the treatment of chronic hepatitis B. Bone mineral density loss has been described in TDF-treated patients with human immunodeficiency virus infection, but limited data exist for patients with chronic hepatitis B. Dual X-ray absorptiometry (DEXA) was used to determine bone mineral density changes in TDF-exposed patients. We evaluated the accuracy of the Fracture Risk Assessment Tool (FRAX) as an alternative to DEXA in clinical practice. METHODS: A total of 170 patients were studied: 122 were exposed to TDF, and 48 were controls. All patients underwent DEXA, and demographic details were recorded. FRAX scores (before and after DEXA) were calculated. RESULTS: TDF was associated with a lower hip T score (P = .02). On univariate and multivariate analysis, advancing age, smoking, lower body mass index, and TDF exposure were independent predictors of low bone mineral density. In addition, the pre-DEXA FRAX score was an accurate predictor of the post-DEXA FRAX treatment recommendation (100% sensitivity and 83% specificity), area under the curve 0.93 (95% CI, .87-.97, P < .001). CONCLUSIONS: TDF-treated patients with chronic hepatitis B have reduced bone mineral density, but the reduction is limited to 1 anatomical site. Age and advanced liver disease are additional contributing factors, underlining the importance of multifactorial fracture risk assessment. FRAX can accurately identify those at greatest risk of osteoporotic fracture.


Assuntos
Adenina/análogos & derivados , Densidade Óssea/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Organofosfonatos/efeitos adversos , Organofosfonatos/uso terapêutico , Inibidores da Transcriptase Reversa/efeitos adversos , Inibidores da Transcriptase Reversa/uso terapêutico , Adenina/efeitos adversos , Adenina/uso terapêutico , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Medição de Risco/métodos , Tenofovir
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