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1.
Hepatology ; 78(5): 1542-1557, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37074026

RESUMO

BACKGROUND AND AIMS: Predicting changes in disease activity and serological endpoints is necessary for the management of patients with chronic hepatitis B (CHB). We examined whether HBV RNA and hepatitis B core-related antigen (HBcrAg), two specialized virological markers proposed to reflect the activity of covalently closed circular DNA, may improve the ability to predict not sustained inactive carrier phase, spontaneous alanine aminotransferase (ALT) flare, HBeAg loss, and HBsAg loss. APPROACH AND RESULTS: Among eligible participants enrolled in the North American Hepatitis B Research Network Adult Cohort Study, we evaluated demographic, clinical, and virologic characteristics, including HBV RNA and HBcrAg, to predict not sustained inactive carrier phase, ALT flare, HBeAg loss, and HBsAg loss through a series of Cox proportional hazard or logistic regression models, controlling for antiviral therapy use. Among the study population, 54/103 participants experienced not sustained inactive carrier phase, 41/1006 had a spontaneous ALT flare, 83/250 lost HBeAg, and 54/1127 lost HBsAg. HBV RNA or HBcrAg were predictive of all 4 events. However, their addition to models of the readily available host (age, sex, race/ethnicity), clinical (ALT, use of antiviral therapy), and viral factors (HBV DNA), which had acceptable-excellent accuracy (e.g., AUC = 0.72 for ALT flare, 0.92 for HBeAg loss, and 0.91 for HBsAg loss), provided only small improvements in predictive ability. CONCLUSION: Given the high predictive ability of readily available markers, HBcrAg and HBV RNA have a limited role in improving the prediction of key serologic and clinical events in patients with CHB.


Assuntos
Hepatite B Crônica , Hepatite B , Adulto , Humanos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , Estudos de Coortes , RNA , DNA Viral , Antígenos do Núcleo do Vírus da Hepatite B , Hepatite B/tratamento farmacológico , Antivirais/uso terapêutico , Biomarcadores
2.
Am J Gastroenterol ; 118(7): 1214-1225, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36599136

RESUMO

INTRODUCTION: Hepatitis B surface antigen (HBsAg) loss is associated with improved long-term outcomes of patients with chronic hepatitis B but is infrequently achieved with current monotherapies. We assessed whether combination strategies that included treatment withdrawal enhanced HBsAg loss. METHODS: A randomized (1:1) trial of tenofovir disoproxil fumarate (TDF) for 192 weeks with or without peginterferon (PegIFN) alfa-2a for the first 24 weeks, followed by withdrawal of TDF at week 192 with 48 weeks of off-treatment follow-up to week 240. The primary end point was HBsAg loss at week 240. RESULTS: Of 201 participants (52% HBeAg positive, 12%/6% genotype A/A2, 7% cirrhosis) randomized to TDF + PegIFN (n = 102) or TDF alone (n = 99), 6 participants had lost HBsAg at the end of the treatment phase (week 192), 5 (5.3%) in the combination group, and 1 (1.0%) in the TDF alone group ( P = 0.09). By week 240, 9 participants had cleared HBsAg, 5.3% in combination, and 4.1% in monotherapy arms ( P = 0.73). HBsAg decline and loss occurred earlier with TDF + PegIFN than TDF, with a ≥1-logIU/mL qHBsAg decline by week 24 in 28% in TDF + PegIFN compared with 6% in TDF ( P = 0.04). HBsAg loss occurred in 7 of 12 (58%) with hepatitis B virus subgenotype A2 (all HBeAg positive) compared with only 2 of 189 (1%) with other hepatitis B virus genotypes and in 8 of 93 (8.6%) HBeAg positive vs 1 of 87 (1.1%) HBeAg negative. DISCUSSION: PegIFN combined TDF followed by protocolized TDF withdrawal led to earlier but not higher percentages of HBsAg clearance. Pretreatment HBeAg positivity and subgenotype A2 were strongly associated with HBsAg clearance.


Assuntos
Hepatite B Crônica , Humanos , Adulto , Tenofovir/uso terapêutico , Antivirais , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Resultado do Tratamento , Vírus da Hepatite B/genética , Polietilenoglicóis/uso terapêutico , DNA Viral
3.
Hepatology ; 75(3): 709-723, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34743343

RESUMO

BACKGROUND AND AIMS: Achieving HBsAg loss is an important landmark in the natural history of chronic hepatitis B (CHB). A more personalized approach to prediction of HBsAg loss is relevant in counseling patients. This study sought to develop and validate a prediction model for HBsAg loss based on quantitative HBsAg levels (qHBsAg) and other baseline characteristics. METHODS: The Hepatitis B Research Network (HBRN) is a prospective cohort including 1240 untreated HBeAg-negative patients (1150 adults, 90 children) with median follow-up of 5.5 years. Incidence rates of HBsAg loss and hepatitis B surface antibody (anti-HBs) acquisition were determined, and a predictor score of HBsAg loss using readily available variables was developed and externally validated. RESULTS: Crude incidence rates of HBsAg loss and anti-HBs acquisition were 1.6 and 1.1 per 100 person-years (PY); 67 achieved sustained HBsAg loss for an incidence rate of 1.2 per 100 PY. Increased HBsAg loss was significantly associated with older age, non-Asian race, HBV phenotype (inactive CHB vs. others), HBV genotype A, lower HBV-DNA levels, and lower and greater change in qHBsAg. The HBRN-SQuARe (sex,∆quantHBsAg, age, race) score predicted HBsAg loss over time with area under the receiver operating characteristic curve (AUROC) (95% CIs) at 1 and 3 years of 0.99 (95% CI: 0.987-1.00) and 0.95 (95% CI 0.91-1.00), respectively. In validation in another cohort of 1253 HBeAg-negative patients with median follow-up of 3.1 years, HBRN SQuARe predicted HBsAg loss at 1 and 3 years with AUROC values of 0.99 (0.98-1.00) and 0.88 (0.77-0.99), respectively. CONCLUSION: HBsAg loss in predominantly untreated patients with HBeAg-negative CHB can be accurately predicted over a 3-year horizon using a simple validated score (HBRN SQuARe). This prognostication tool can be used to support patient care and counseling.


Assuntos
Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Hepatite B Crônica , Adulto , Fatores Etários , Criança , Etnicidade/estatística & dados numéricos , Feminino , Seguimentos , Anticorpos Anti-Hepatite B/análise , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/análise , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/imunologia , Humanos , Incidência , Masculino , Valor Preditivo dos Testes , Prognóstico , Testes Sorológicos/métodos , Testes Sorológicos/estatística & dados numéricos , Resposta Viral Sustentada
4.
Clin Gastroenterol Hepatol ; 20(8): 1766-1775, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34329775

RESUMO

BACKGROUND & AIMS: Chronic hepatitis B (CHB) infection remains the most frequent etiology of hepatocellular carcinoma globally as well as a major cause of cirrhosis. Despite vaccination, substantial numbers of persons have already been infected with hepatitis B virus and remain at risk of progressive liver disease. METHODS: In 2004, a CHB management algorithm was developed by a panel of North American hepatologists, which was subsequently updated in 2006, 2008, and 2015. Since the most recent version, several developments have altered the management of CHB. Tenofovir alafenamide, with a more favorable safety profile than tenofovir disoproxil fumarate, has been introduced as an initial antiviral choice as well as an alternative for long-term therapy. Quantitation of hepatitis B surface antigen is becoming more widely available in clinical practice, with implications for monitoring response to treatment. Additionally, there has been a shift in how the natural history of CHB is perceived, as newer evidence has challenged the concept that during the immunotolerant phase of infection disease progression is not a concern. Finally, recent analyses indicate that in the United States, the average age of patients with CHB has increased, implying that the presence of comorbidities, including metabolic liver disease, increasing use of biologics associated with aging will increasingly affect disease management. RESULTS: This updated algorithm is intended to serve as a guide to manage CHB while new antiviral strategies are developed. CONCLUSIONS: Recommendations have been based on evidence from the scientific literature, when possible, as well as clinical experience and consensus expert opinion. Points of continued debate and areas of research need are also described.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Algoritmos , Antivirais/uso terapêutico , Carcinoma Hepatocelular/etiologia , Vírus da Hepatite B , Hepatite B Crônica/complicações , Humanos , Neoplasias Hepáticas/etiologia , Estados Unidos
5.
Hepatology ; 73(5): 1637-1651, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32860463

RESUMO

BACKGROUND AND AIMS: Hepatitis B virus (HBV) precore (PC) and dual basal core promoter (BCP) mutations halt and down-regulate hepatitis B e antigen (HBeAg) production respectively. PC mutation is rarely associated with HBV genotype A. We sought to examine the association of these variants with HBV genotypes, age, and HBeAg status in a racially diverse population in North America. Prospective study included 1,036 (808 adults, 228 children) participants in the Hepatitis B Research Network. PC and BCP variants were determined by Sanger sequencing, and dominant HBV species (>50%) were reported. APPROACH AND RESULTS: Median age was 36.3 years (range, 2-80), 44.6% HBeAg(+), 74.2% Asians, 13.3% black, and 9.7% white. The dominant PC variant was present in 29.4% participants, including 20 with subgenotype A1 or A2. Seventeen of 20 participants with genotype A and PC had a compensatory C1858T mutation. In the HBeAg(+) cohort, the prevalence of PC and/or BCP variants increased from 14.4% in the first two decades to 51% after 40 years of age. Among those aged 2-18, 52% and 83% with dominant PC and BCP variants were HBeAg(+) compared to 3.8% and 29% in the >40 years age group. HBeAg clearance rates were significantly higher for those with dominant PC or BCP variants: 24.4 and 15.0 per 100 person-years compared to 6.0 in wild-type HBV (P < 0.0001). CONCLUSIONS: PC variants can be present in HBV genotype A and are usually associated with C1858T, which preserves the pregenome encapsidation sequence. Selection of PC and BCP variants occurred at a young age, with increasing prevalence across age groups. HBeAg(+) participants with dominant PC and BCP variants progressed to the HBeAg(-) phase of chronic HBV infection significantly faster. This finding has potential clinical and therapeutic implications.


Assuntos
Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Variação Genética/genética , Genótipo , Antígenos E da Hepatite B/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , América do Norte , Estudos Prospectivos , Grupos Raciais , Análise de Sequência de DNA , Adulto Jovem
6.
Hepatology ; 74(5): 2395-2409, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34133774

RESUMO

BACKGROUND AND AIMS: The clinical utility of two biomarkers, hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg), as compared to conventional markers of HBV replication and disease activity, is unclear. APPROACH AND RESULTS: Untreated participants in the North American Hepatitis B Research Network Adult Cohort Study were categorized by chronic hepatitis B (CHB) phases based on HBsAg and HBeAg status and HBV DNA and alanine aminotransferase (ALT) levels. HBV RNA and HBcrAg were measured (Abbott HBV pgRNA Research Assay and Fujirebio Lumipulse Immunoassay, respectively), and cross-sectional associations with conventional CHB markers were tested. Among 1,409 participants across all CHB phases, median HBV DNA was 3.8 log10 IU/mL and ALT was 34 U/L. HBV RNA was quantifiable in 99% of HBeAg+ and 58% of HBeAg- participants; HBcrAg was quantifiable in 20% of HBeAg+ (above linear range in the other 80%) and 51% of HBeAg- participants. Both markers differed across CHB phases (P < 0.001), with higher levels in the HBeAg+ and HBeAg- immune active phases. HBV RNA and HBcrAg correlated moderately strongly with HBV DNA in both HBeAg+ and HBeAg- phases (HBV RNA: e+ ρ = 0.84; e- ρ = 0.78; HBcrAg: e+ ρ = 0.66; e- ρ = 0.56; P for all, <0.001), but with HBsAg levels among HBeAg+ phases only (HBV RNA: e+ ρ = 0.71; P < 0.001; e- ρ = 0.18; P = 0.56; HBcrAg: e+ ρ = 0.51; P < 0.001; e- ρ = 0.27; P < 0.001). Associations of higher HBV RNA and HBcrAg levels with higher ALT, APRI, and Fibrosis-4 levels were consistent in HBeAg- , but not HBeAg+ , phases. CONCLUSIONS: Despite clear relationships between HBV RNA and HBcrAg levels and CHB phases, these markers have limited additional value in differentiating CHB phases because of their strong association with HBV DNA and, to a lesser extent, with clinical disease indicators.


Assuntos
Antígenos do Núcleo do Vírus da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/epidemiologia , RNA Viral/sangue , Adulto , Alanina Transaminase/sangue , Biomarcadores/sangue , Estudos Transversais , DNA Viral/sangue , DNA Viral/genética , Feminino , Seguimentos , Genótipo , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , RNA Viral/genética
7.
Hepatology ; 73(6): 2124-2140, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32936969

RESUMO

BACKGROUND AND AIMS: Outcomes of persons with chronic hepatitis B virus (HBV) infection in the era of antiviral therapy (AVT) are not well characterized. We determined the incidence and factors associated with clinical outcomes in a multiethnic, North American cohort of adults with chronic HBV infection, who were not on AVT at enrollment. APPROACH AND RESULTS: Adults with chronic HBV infection, not receiving AVT, and without a history of decompensation, HCC, or liver transplantation (LT), were prospectively followed. Participants with known human immunodeficiency virus (HIV), hepatitis C virus, or hepatitis D virus (HDV) coinfection were excluded. During follow-up, treatment could be initiated per standard of care. Clinical outcomes included: incident cirrhosis, decompensation, HCC, OLT, and HBV-related death. Among 1,418 participants analyzed, 51.5% were women, median age was 41.1 years, 75% were Asian, 10% White, 13% Black, 24% HBeAg(+), and 1.5% cirrhosis at baseline. During the study, 274 started treatment, 83 had an alanine aminotransferase flare, 118 of 330 initially HBeAg(+) became HBeAg(-), and 90 of 1,329 became HBsAg(-). After 6,641 person-years follow-up, 8 participants (4 of 21 with baseline cirrhosis) had 12 clinical outcomes (2 decompensation, 5 HCC, 2 OLT, and 3 HBV-related deaths) and 19 of 1,397 had incident cirrhosis. Twenty-one of 26 participants had first outcome before treatment, none had become HBsAg(-), whereas 5/9 HBeAg(+) had become HBeAg(-) at time of first outcome. Cumulative percentage of clinical outcomes was 16% at year 4 in participants with baseline cirrhosis and 2% (including incident cirrhosis) at year 7 in those without. CONCLUSIONS: Incidence of adverse outcomes was low in this closely monitored, large cohort of North American adults with predominantly inactive, chronic HBV without cirrhosis. Our data highlight the benefits of HBsAg loss and the importance of early diagnosis and treatment to prevent cirrhosis and other complications of chronic HBV infection.


Assuntos
Alanina Transaminase/sangue , Carcinoma Hepatocelular/epidemiologia , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/epidemiologia , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/epidemiologia , Adulto , Antivirais , Feminino , Antígenos de Superfície da Hepatite B/sangue , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Ontário/epidemiologia , Estudos Prospectivos , Estados Unidos/epidemiologia
8.
PLoS Pathog ; 15(4): e1007715, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30998783

RESUMO

Hepatitis B virus (HBV) persists with global and virus-specific T-cell dysfunction, without T-cell based correlates of outcomes. To determine if γδT-cells are altered in HBV infection relative to clinical status, we examined the frequency, phenotype and function of peripheral blood Vδ1+ and Vδ2+γδT-cells by multi-parameter cytometry in a clinically diverse North American cohort of chronic hepatitis B (CHB), acute hepatitis B (AHB) and uninfected control subjects. We show that circulating γδT-cells were comprised predominantly of CD3hiCD4- Vδ2+γδT-cells with frequencies that were 2-3 fold higher among Asian than non-Asian Americans and inversely correlated with age, but without differences between CHB, AHB and control subjects. However, compared to control subjects, CHB was associated with increased TbethiEomesdim phenotype in Vδ2+γδT-cells whereas AHB was associated with increased TbethiEomesdim phenotype in Vδ1+γδT-cells, with significant correlations between Tbet/Eomes expression in γδT-cells with their expression of NK and T-cell activation and regulatory markers. As for effector functions, IFNγ/TNF responses to phosphoantigens or PMA/Ionomycin in Vδ2+γδT-cells were weaker in AHB but preserved in CHB, without significant differences for Vδ1+γδT-cells. Furthermore, early IFNγ/TNF responses in Vδ2+ γδT-cells to brief PMA/Ionomycin stimulation correlated inversely with serum ALT but not HBV DNA. Accordingly, IFNγ/TNF responses in Vδ2+γδT-cells were weaker in patients with CHB with hepatitis flare compared to those without hepatitis flares, and this functional deficit persisted beyond clinical resolution of CHB flare. We conclude that circulating γδT-cells show distinct activation and differentiatiation in acute and chronic HBV infection as part of lymphoid stress surveillance with potential role in clinical outcomes.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Biomarcadores/análise , Estudos de Coortes , Feminino , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores de Antígenos de Linfócitos T gama-delta/sangue , Adulto Jovem
10.
Am J Gastroenterol ; 114(11): 1753-1763, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31658127

RESUMO

INTRODUCTION: Patients with hepatitis B early antigen (HBeAg)-negative chronic hepatitis B (CHB) and low-level viremia are a heterogeneous group. Identifying those at risk of developing active CHB requiring antiviral therapy is important. In this study, we prospectively characterize incidence rates and predictors of transitioning from inactive to active CHB in a North American adult cohort. METHODS: Participants in the multicenter National Institute of Diabetes and Digestive and Kidney Diseases Hepatitis B Research Network cohort who were HBeAg negative with baseline hepatitis B virus (HBV) DNA ≤ 10,000 IU/mL were included in the study. Cox regression models were used to estimate the proportion of individuals in 3 baseline HBV DNA categories (≤100, 101 to ≤2,000, and 2,001 to ≤10,000 IU/mL) who developed phase transition defined by HBV DNA > 10,000 IU/mL and alanine aminotransferase (ALT) > 2× upper limit of normal or initiated treatment during follow-up. RESULTS: Of 970 participants meeting inclusion criteria, 15% experienced phase transition or initiated treatment over a median follow-up of 4 years: 9% of those with baseline HBV DNA ≤ 100 IU/mL, 14% with HBV DNA 101 to ≤2,000 IU/mL, and 24% with HBV DNA 2,001 to ≤10,000 IU/mL (P < 0.001). The overall rate of phase transition or treatment initiation was 7.6 per 100 person-years: 4.6 in those with HBV DNA ≤ 100 IU/mL, 6.8 in those with HBV DNA 101 to ≤2,000 IU/mL, and 12.2 in those with HBV DNA 2,001 to ≤10,000 IU/mL (P < 0.001). Factors independently associated with higher rate of phase transition or treatment initiation included HBV genotype B or C, higher baseline ALT and HBV DNA levels, lower platelet count, quantitative hepatitis B surface antigen > 1,000 IU/mL, and hyperlipidemia. Only higher ALT, higher HBV DNA, and lower platelets were associated with phase transition when patients starting treatment were censored. DISCUSSION: Most adults in this North American cohort with HBeAg-negative CHB and low-level viremia remained inactive and off treatment over 4 years. Transition from inactive to active CHB is infrequent and predominantly associated with viral rather than host factors.


Assuntos
Antivirais/uso terapêutico , Antígenos E da Hepatite B/análise , Vírus da Hepatite B , Hepatite B , Viremia , Adulto , Portador Sadio/imunologia , DNA Viral/análise , Feminino , Hepatite B/epidemiologia , Hepatite B/imunologia , Hepatite B/terapia , Hepatite B/virologia , Vírus da Hepatite B/imunologia , Vírus da Hepatite B/isolamento & purificação , Humanos , Testes de Função Hepática/métodos , Testes de Função Hepática/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Gravidade do Paciente , Testes Sorológicos/métodos , Testes Sorológicos/estatística & dados numéricos , Tempo para o Tratamento/normas , Viremia/diagnóstico , Viremia/epidemiologia , Viremia/etiologia
12.
J Clin Gastroenterol ; 52(3): 255-261, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28323748

RESUMO

BACKGROUND AND AIMS: Antiviral therapy is recommended for pregnant women with chronic hepatitis B (CHB) and hepatitis B virus (HBV) DNA>200,000 IU/mL, but there is less consensus on management of women who discontinue therapy in anticipation of pregnancy or who become pregnant while on therapy. The goal of this study was to describe flares in alanine aminotransferase (ALT) during pregnancy and postpartum in CHB women with current and/or prior treatment. METHODS: This was a multicenter, retrospective study of 67 pregnancies in 56 CHB women treated before and/or during pregnancy. Main outcomes were frequency, severity, and resolution of ALT flare (≥5× upper limit of normal or ≥3× baseline, whichever was higher). RESULTS: During pregnancy, ALT flares (95 to 1064 U/L) were observed in 16% (7/43) of women who stopped treatment before pregnancy and 31% (4/13) of women who discontinued treatment during first trimester, many of whom had high HBV DNA levels (4.9 to 8.0 log IU/mL). No flares (0/11) were observed in women who continued treatment. Postpartum ALT flares (104 to 1584 U/L) were observed in 0% (0/15) of women who were completely untreated during pregnancy, 29% (2/7) of women who discontinued treatment in first trimester, 33% (3/9) of women who stopped treatment at delivery, and 22% (4/18) of women who continued treatment postpartum. CONCLUSIONS: In previously treated women with CHB, ALT flares were common during pregnancy and postpartum, especially if antiviral therapy was discontinued shortly before pregnancy, during first trimester, or at delivery. Thus, these pregnant women should be monitored closely throughout pregnancy and the early postpartum period; larger studies are needed to further characterize the natural history of HBV infection during pregnancy and postpartum.


Assuntos
Alanina Transaminase/sangue , Antivirais/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , DNA Viral/sangue , Feminino , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/virologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo
13.
Proc Natl Acad Sci U S A ; 112(32): E4354-63, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26195743

RESUMO

Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients' homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE(2)RD), which addresses all these impediments on a single platform. The NE(2)RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE(2)RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE(2)RD's broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients' homes.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas e Procedimentos Diagnósticos/instrumentação , Eletricidade , Nanoestruturas/química , Linhagem Celular Tumoral , Coinfecção/diagnóstico , Meio Ambiente , Ensaio de Imunoadsorção Enzimática , Desenho de Equipamento , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microfluídica , Concentração Osmolar , Reprodutibilidade dos Testes , Temperatura
14.
Gastroenterology ; 150(3): 684-695.e5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26684441

RESUMO

BACKGROUND & AIMS: T cells play a critical role in viral infection. We examined whether T-cell effector and regulatory responses can define clinical stages of chronic hepatitis B (CHB). METHODS: We enrolled 200 adults with CHB who participated in the National Institutes of Health-supported Hepatitis B Research Network from 2011 through 2013 and 20 uninfected individuals (controls). Peripheral blood lymphocytes from these subjects were analyzed for T-cell responses (proliferation and production of interferon gamma and interleukin 10) to overlapping hepatitis B virus (HBV) peptides (preS, S, preC, core, and reverse transcriptase), influenza matrix peptides, and lipopolysaccharide. T-cell expression of regulatory markers FOXP3, programmed death-1, and cytotoxic T lymphocyte-associated antigen-4 was examined by flow cytometry. Immune measures were compared with clinical parameters, including physician-defined immune-active, immune-tolerant, or inactive CHB phenotypes, in a blinded fashion. RESULTS: Compared with controls, patients with CHB had weak T-cell proliferative, interferon gamma, and interleukin 10 responses to HBV, with increased frequency of circulating FOXP3(+)CD127(-) regulatory T cells and CD4(+) T-cell expression of programmed death-1 and cytotoxic T lymphocyte-associated antigen-4. T-cell measures did not clearly distinguish between clinical CHB phenotypes, although the HBV core-specific T-cell response was weaker in hepatitis B e antigen (HBeAg)(+) than HBeAg(-) patients (percent responders: 3% vs 23%; P = .00008). Although in vitro blockade of programmed death-1 or cytotoxic T lymphocyte-associated antigen-4 increased T-cell responses to HBV, the effect was weaker in HBeAg(+) than HBeAg(-) patients. Furthermore, T-cell responses to influenza and lipopolysaccharide were weaker in CHB patients than controls. CONCLUSIONS: HBV persists with virus-specific and global T-cell dysfunction mediated by multiple regulatory mechanisms, including circulating HBeAg, but without distinct T-cell-based immune signatures for clinical phenotypes. These findings suggest additional T-cell-independent or regulatory mechanisms of CHB pathogenesis that warrant further investigation.


Assuntos
Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/virologia , Ativação Linfocitária , Linfócitos T/virologia , Adulto , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Feminino , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/imunologia , Interações Hospedeiro-Patógeno , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/metabolismo , Lipopolissacarídeos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Orthomyxoviridae/imunologia , Fenótipo , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/virologia , Estados Unidos
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