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1.
J Hepatol ; 62(2): 486-91, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25308176

RESUMO

HBV-DNA integration frequently occurs in HBV-related hepatocellular carcinoma (HCC), but whether HBV antigens are expressed in HCC cells and can be targeted by immune therapeutic strategies remains controversial. Here, we first characterized HBV antigen expression in HCC metastases, occurring in a patient who had undergone liver transplantation for HBV-related HCC. We then deployed for the first time in HCC autologous T cells, genetically modified to express an HBsAg specific T cell receptor, as therapy against chemoresistant extrahepatic metastases. We confirmed that HBV antigens were expressed in HCC metastases (but not in the donor liver) and demonstrated that tumour cells were recognized in vivo by lymphocytes, engineered to express an HBV-specific T cell receptor (TCR). Gene-modified T cells survived, expanded and mediated a reduction in HBsAg levels without exacerbation of liver inflammation or other toxicity. Whilst clinical efficacy was not established in this subject with end-stage metastatic disease, we confirm the feasibility of providing autologous TCR-redirected therapy against HCC and advocate this strategy as a novel therapeutic opportunity in hepatitis B-associated malignancies.


Assuntos
Carcinoma Hepatocelular/secundário , Antígenos de Superfície da Hepatite B/metabolismo , Imunoterapia/métodos , Neoplasias Hepáticas/patologia , Receptores de Antígenos de Linfócitos T/uso terapêutico , Tacrolimo/uso terapêutico , Idoso , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/terapia , Evolução Fatal , Seguimentos , Humanos , Imunossupressores/uso terapêutico , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/terapia , Masculino , Metástase Neoplásica
2.
Gastroenterology ; 139(2): 483-90, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20451520

RESUMO

BACKGROUND & AIMS: The accurate identification of inactive (serum HBV-DNA persistently or=20,000 IU/mL (AC2): 883 (0.5-7838) vs 4233 (164-82,480) IU/mL, P=.002. HBV infection was less productive in IC and AC1 than AC2 (log10 HBV-DNA/HBsAgsl ratios 0.25 and 0.49 vs 2.06, respectively, P<.001) and in chronic hepatitis than cirrhosis (1.97 vs 2.34, respectively; P=.023). The combined single point quantification of HBsAg (<1000 IU/mL) and HBV-DNA (

Assuntos
Portador Sadio , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/imunologia , Hepatite B Crônica/diagnóstico , Ativação Viral , Adolescente , Adulto , Idoso , Biomarcadores/sangue , DNA Viral/sangue , Feminino , Seguimentos , Genótipo , Vírus da Hepatite B/genética , Hepatite B Crônica/epidemiologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Testes Sorológicos , Fatores de Tempo , Adulto Jovem
3.
World J Gastroenterol ; 14(40): 6154-62, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18985805

RESUMO

AIM: To investigate the usefulness of transient elastography by Fibroscan (FS), a rapid non-invasive technique to evaluate liver fibrosis, in the management of chronic hepatitis B virus (HBV) carriers. METHODS: In 297 consecutive HBV carriers, we studied the correlation between liver stiffness (LS), stage of liver disease and other factors potentially influencing FS measurements. In 87 chronic hepatitis B (CHB) patients, we monitored the FS variations according to the spontaneous or treatment-induced variations of biochemical activity during follow-up. RESULTS: FS values were 12.3 +/- 3.3 kPa in acute hepatitis, 10.3 +/- 8.8 kPa in chronic hepatitis, 4.3 +/- 1.0 kPa in inactive carriers and 4.6 +/- 1.2 kPa in blood donors. We identified the cut-offs of 7.5 and 11.8 kPa for the diagnosis of fibrosis >or= S3 and cirrhosis respectively, showing 93.9% and 86.5% sensitivity, 88.5% and 96.3% specificity, 76.7% and 86.7% positive predictive value (PPV), 97.3% and 96.3% negative predictive value (NPV) and 90.1% and 94.2% diagnostic accuracy. At multivariate analysis in 171 untreated carriers, fibrosis stage (t = 13.187, P < 0.001), active vs inactive HBV infection (t = 6.437, P < 0.001), alanine aminotransferase (ALT) (t = 4.740, P < 0.001) and HBV-DNA levels (t = or-2.046, P = 0.042) were independently associated with FS. Necroinflammation score (t = 2.158, > 10/18 vs

Assuntos
Alanina Transaminase/sangue , Portador Sadio , Ensaios Enzimáticos Clínicos , Técnicas de Imagem por Elasticidade , Hepatite B Crônica/diagnóstico , Hepatite B/diagnóstico , Cirrose Hepática/diagnóstico , Fígado/patologia , Doença Aguda , Adulto , Idoso , Antivirais/uso terapêutico , Biópsia , Estudos Transversais , Elasticidade , Feminino , Hepatite B/complicações , Hepatite B/tratamento farmacológico , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Humanos , Fígado/enzimologia , Fígado/virologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Adulto Jovem
4.
Antivir Ther ; 8(6): 519-30, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14760885

RESUMO

BACKGROUND AND AIMS: Standard models simulate the dynamics of hepatitis C virus (HCV) infection using HCV RNA kinetics and show a correlation between the clearance of infected hepatocytes and response to interferon. However, they are unable to predict whether the response will be maintained. The aim of our work was to identify criteria by which sustained responses may be predicted and defined. METHODS: In our model the clearance rate of infected cells is a function of their number and the baseline rate is computed by the alanine aminotransferase (ALT) kinetics during the first month of therapy. We simulated the variations of viral and infected cell loads in 31 consecutive patients treated with IFN-alpha2b 3-5 MU every other day, with or without ribavirin, for 6 or 12 months depending on HCV genotype. RESULTS: At baseline the computed (in 28 of 31 cases) percentage of infected cells was lower in seven sustained responders (mean: 11.7%, range: 1-24.6%) than in 14 transient responders (mean: 28.2%, range: 7.4-75.5%) and in seven non-responders (mean: 41%, range: 8.8-86%) (P=0.036). At the end of therapy the computed infected cell number was <100 cells/ml of extracellular fluid in all sustained responders (mean: 18.4, range: 1.7-48), in three transient responders (mean: 3500, range: 1.52-17500) and in none non-responders (mean: 28500, range: 1200-96000) (P=0.003). Overall of 10 patients with less than 100 infected cells/ml at the end of therapy seven (six had combination therapy) showed sustained response. All three relapsers received interferon monotherapy. CONCLUSION: The analysis of infected cells dynamics using the new model might be useful to tailor treatment duration in patients with combination therapy.


Assuntos
Alanina Transaminase/sangue , Antivirais/administração & dosagem , Hepatite C/tratamento farmacológico , Interferons/administração & dosagem , RNA Viral/sangue , Ribavirina/administração & dosagem , Quimioterapia Combinada , Feminino , Hepatite C/fisiopatologia , Hepatite C/virologia , Humanos , Masculino , Modelos Teóricos
5.
PLoS One ; 9(10): e110782, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25350115

RESUMO

BACKGROUND AND AIMS: The virus/host interplay mediates liver pathology in chronic HBV infection. MiRNAs play a pivotal role in virus/host interactions and are detected in both serum and HBsAg-particles, but studies of their dynamics during chronic infection and antiviral therapy are missing. We studied serum miRNAs during different phases of chronic HBV infection and antiviral treatment. METHODS: MiRNAs were profiled by miRCURY-LNA-Universal-RT-miRNA-PCR (Exiqon-A/S) and qPCR-panels-I/II-739-miRNA-assays and single-RT-q-PCRs. Two cohorts of well-characterized HBsAg-carriers were studied (median follow-up 34-52 months): a) training-panel (141 sera) and HBsAg-particles (32 samples) from 61 HBsAg-carriers and b) validation-panel (136 sera) from 84 carriers. RESULTS: Thirty-one miRNAs were differentially expressed in inactive-carriers (IC) and chronic-hepatitis-B (CHB) with the largest difference for miR-122-5p, miR-99a-5p and miR-192-5p (liver-specific-miRNAs), over-expressed in both sera and HBsAg-particles of CHB (ANOVA/U-test p-values: <0.000001/0.000001; <0.000001/0.000003; <0.000001/0.000005, respectively) and significantly down-regulated during- and after-treatment in sustained-virological-responders (SVR). MiRNA-profiles of IC and SVR clustered in the heatmap. Liver-miRNAs were combined with miR-335, miR-126 and miR-320a (internal controls) to build a MiR-B-Index with 100% sensitivity, 83.3% and 92.5% specificity (-1.7 cut-off) in both training and validation cohorts to identify IC. MiR-B-Index (-5.72, -20.43/14.38) correlated with ALT (49, 10/2056 U/l, ρ = -0.497, p<0.001), HBV-DNA (4.58, undetectable/>8.3 Log10 IU/mL, ρ = -0.732, p<0.001) and HBsAg (3.40, 0.11/5.49 Log10 IU/mL, ρ = -0.883, p<0.001). At multivariate analysis HBV-DNA (p = 0.002), HBsAg (p<0.001) and infection-phase (p<0.001), but not ALT (p = 0.360) correlated with MiR-B-Index. In SVR to Peg-IFN/NUCs MiR-B-Index improved during-therapy and post-treatment reaching IC-like values (5.32, -1.65/10.91 vs 6.68, 0.54/9.53, p = 0.324) beckoning sustained HBV-immune-control earlier than HBsAg-decline. CONCLUSIONS: Serum miRNA profile change dynamically during the different phases of chronic HBV infection. We identified a miRNA signature associated with both natural-occurring and therapy-induced immune control of HBV infection. The MiR-B-Index might be a useful biomarker for the early identification of the sustained switch from CHB to inactive HBV-infection in patients treated with antivirals.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , MicroRNAs/genética , Adulto , Idoso , Antivirais/uso terapêutico , Análise por Conglomerados , Estudos de Coortes , Biologia Computacional , Feminino , Seguimentos , Perfilação da Expressão Gênica , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Carga Viral , Adulto Jovem
6.
Liver Int ; 27(5): 612-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17498245

RESUMO

BACKGROUND: Early identification of patients at a higher risk of rapidly progressive recurrent hepatitis post liver transplantation (LT) could help to tailor antiviral therapy. METHODS: We studied the correlation between early post-LT viral load and the histological and clinical outcomes of 49 consecutive patients (34 males, median age 55 years) in whom viraemia was monitored at days 0, 1, 7, 30, 180 and 365 after LT. RESULTS: Hepatitis C recurred at histology in 38 of 42 (90.5%) patients. Early viral load after LT was higher in patients with rapidly progressive hepatitis C recurrence (day 7 median HCV-RNA levels: 5.84 vs 4.93 Log(10) IU/ml, P=0.003). Day 7 HCV-RNA levels >/=2.5 x 10(5) IU/ml, donor age >60 years and rejection episodes were independently associated with progression to cirrhosis within one year post-LT [P=0.018, odds ratio (OR) 27.59; P=0.043, OR 13.85 and P=0.048, OR 9.95, respectively]. Day 7 viraemia and rejection episodes were independently associated with 5-years survival. Day 7 viraemia, in combination with acute hepatitis and/or donor age, showed 80% sensitivity, 94% specificity and 90.5% diagnostic accuracy to identify severe recurrence. CONCLUSIONS: Early post-LT HCV-RNA correlates with the severity of hepatitis C recurrence and in combination with donor age (>60 years) and rejections, identifies patients with a high risk of severe recurrence and candidates of cost-effective pre-emptive antiviral therapy.


Assuntos
Rejeição de Enxerto/virologia , Hepatite C Crônica/virologia , Transplante de Fígado/efeitos adversos , RNA Viral/sangue , Adulto , Fatores Etários , Idoso , Feminino , Seguimentos , Rejeição de Enxerto/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Fatores de Tempo , Carga Viral
7.
J Hepatol ; 42(1): 61-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15629508

RESUMO

BACKGROUND/AIMS: Dendritic cells (DCs) play a key role in immune responses through antigen presentation and cytokine secretion. Hepatitis C virus (HCV) is able to escape elimination by the immune system and often establishes a chronic infection. To investigate whether DC dysfunction is involved in this process, we have studied monoycte-derived DCs (Mo-DCs) and plasmacytoid DCs (pDCs), which produce large amounts of IFN-alpha, from chronic HCV patients and healthy donors. METHODS: We have assessed TNF-alpha and IFN-alpha production by pDCs using intracellular staining after total PBMCs stimulation with unmethylated CG dinucleotides (CpGs). The induction of allogeneic T cell proliferation by immature Mo-DCs was measured using the MLR assay. The up-regulation of maturation markers and the production of TNF-alpha in response to LPS were analyzed using flow cytometry and ELISA, respectively. RESULTS: We have detected comparable frequencies of pDCs producing TNF-alpha and IFN-alpha in both chronic HCV patients and healthy donors and we have found that immature Mo-DCs from both patients and donors similarly induce allogeneic T cell proliferation and mature and secrete TNF-alpha in response to LPS. CONCLUSIONS: Our results demonstrate that both pDC and Mo-DCs are not impaired in HCV infected patients.


Assuntos
Células Dendríticas/fisiologia , Hepatite C Crônica/imunologia , Adulto , Idoso , Doadores de Sangue , Feminino , Humanos , Interferon-alfa/biossíntese , Teste de Cultura Mista de Linfócitos , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Plasmócitos/citologia , Fator de Necrose Tumoral alfa/biossíntese
8.
J Med Virol ; 75(2): 358-65, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15602718

RESUMO

Torque Teno virus (TTV) has been demonstrated to be present persistently in the blood of healthy individuals without evidence that it causes any disease process. The levels of TTV vary in patients co-infected with other viruses and there has been considerable speculation as to whether TTV contributes to pathogenesis by other viruses or if the varying levels might be related to immune activation in the host. In the present study, the load of TTV was examined in plasma and peripheral blood mononuclear cells (PBMCs) following immunization of subjects with either influenza (a recall antigen) or hepatitis B virus (HBV) (a new antigenic exposure). The results overall did not indicate a significant change in TTV titers over a 90 day observation period; however, when TTV genogroup was taken into consideration there was an increase in viral load in plasma at some time points for subjects persistently infected with genogroup 3. While this was observed in both influenza and HBV immunized subjects, the effect was more profound in HBV vaccination. Thus, it appears that exposure to a new antigen rather than a recall antigen may stimulate TTV replication more effectively. The data further suggest that investigating the interactions between TTV and its host might require to examine specifically each TTV genogroup separately in order to determine if certain TTV types have any role in disease pathogenesis.


Assuntos
Infecções por Circoviridae/imunologia , Vacinas contra Hepatite B/efeitos adversos , Vacinas contra Influenza/efeitos adversos , Torque teno virus/isolamento & purificação , Ativação Viral/imunologia , Adulto , Idoso , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Circoviridae/sangue , Infecções por Circoviridae/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Torque teno virus/imunologia , Carga Viral
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