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2.
J Viral Hepat ; 15(6): 442-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18221304

RESUMO

Thymosin alpha-1 (Talpha1) has been shown to be effective in chronic hepatitis B treatment. This study investigated the effect of Talpha1 and interferon-alpha (IFNalpha) on cytokine production by peripheral blood mononuclear cells (PBMCs) of 12 patients with eAg-negative chronic hepatitis B (HBV). We evaluated the effect of incubation with Talpha1, IFNalpha or both on the synthesis of T-helper 1 (Th1) cytokines [interleukin-2 (IL-2), IFNgamma] and Th2 cytokines (IL-4, IL-10) and of antiviral protein 2',5'-oligoadenylate synthetase (2',5'-OAS) in patients and in a group of 10 healthy controls. Concerning Th1 profile, controls showed lower IL-2 synthesis than HBV patients. In HBV setting, IFNalpha/Talpha1 combination was able to increase IL-2 production significantly, when compared with baseline condition. About the Th2-cytokines, controls showed statistically lower synthesis of IL-4 and higher production of IL-10, than HBV patients. In these latter, IFNalpha increased the synthesis of IL-10 compared with baseline. Interestingly, both Talpha1 alone and the IFNalpha/Talpha1 combination reversed this effect. Finally, compared with baseline, the synthesis of 2',5'-OAS was significantly higher in the presence of Talpha1 and IFNalpha alone, and in the presence of IFNalpha/Talpha1 association, while no differences were found between controls and HBV patients. In conclusion, in PBMCs from eAg-negative HBV patients, Talpha1 alone was able to increase the antiviral protein synthesis, while in association with IFNalpha, it stimulated the IL-2 synthesis and inhibited the IFN-induced IL-10 production. These results need further investigations, but reinforce the idea of an immunotherapeutic approach for chronic hepatitis B.


Assuntos
2',5'-Oligoadenilato Sintetase/biossíntese , Antivirais/farmacologia , Hepatite B Crônica/metabolismo , Interferon-alfa/farmacologia , Interleucina-2/biossíntese , Interleucina-4/biossíntese , Timosina/análogos & derivados , Adulto , Células Cultivadas , Feminino , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/imunologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Células Th2/efeitos dos fármacos , Células Th2/metabolismo , Timalfasina , Timosina/farmacologia
3.
J Viral Hepat ; 12(5): 525-30, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16108769

RESUMO

SUMMARY: The relationship between the balance of helper T-cell type 1 (Th1) or type 2 (Th2) cytokines and the clinical course of hepatitis C virus (HCV) infection is unclear. We evaluated Th1 [interleukin (IL)-2, interferon-gamma (IFN-gamma)] and Th2 cytokine (IL-4, IL-10) and 2,5-oligoadenylate synthetase (OAS, an IFN-induced antiviral protein) production by peripheral blood mononuclear cells from 10 healthy anti-HCV-positive individuals (group A), 10 HCV-RNA-positive with persistently normal alanine aminotransferase (ALT) levels (group B), 10 HCV-RNA-positive with abnormal ALT (group C) and 10 uninfected healthy controls. IL-2 production was significantly increased in group B when compared with all the other groups. No difference was found for IFN-gamma. IL-4 was significantly higher in group C than in both group B (P = 0.0006) and controls (P = 0.004). Compared with controls, IL-10 was significantly decreased in group A (P = 0.013) and B (P = 0.004). The production of 2,5-OAS was significantly higher in group B than in A (P = 0.04) and in C (P = 0.004). Finally, in all HCV-RNA-positive patients, a significant correlation was found between ALT and both IL-2 (r = -0.78; P = 0.0008) and IL-4 (r = 0.75; P = 0.0008). IN CONCLUSION: (i) subjects who cleared HCV showed a cytokine profile similar to controls; (ii) a preferential shift towards a Th1 profile seems associated with a more favourable clinical outcome in chronic hepatitis C; and (iii) a prevalent Th2 profile seems implicated in HCV pathogenesis and severity of liver disease.


Assuntos
Citocinas/sangue , Hepatite C/sangue , Hepatite C/patologia , Leucócitos Mononucleares/metabolismo , Adulto , Feminino , Hepacivirus/imunologia , Hepatite C/tratamento farmacológico , Hepatite C/imunologia , Humanos , Interferon gama/sangue , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde
4.
Arch Virol ; 150(2): 261-71, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15480856

RESUMO

To describe the virological profile of HCV in HBV/HCV co-infection, we investigated the variability of HVR-1 and NS5A domains, which may be involved in viral persistence and replication efficiency. We studied 95 patients: 37 with serological markers of HBV/HCV co-infection, 33 with single HBV and 25 with single HCV infection. HVR-1 complexity and NS5A gene variability were respectively explored by means of PCR-SSCP and direct sequencing. Serum HBV genomes were detected in all coinfected patients: 19 also had circulating HCV particles (group BC-I), whereas HCV were undetectable in the other 18 (group BC-II). Group BC-I was characterised by a significantly lower HBV replication capacity, that reflects the replicative dominance of HCV, although the dominant virus had the same degree of variability as the HCV in single infection. HBV viral load was higher in group BC-II, but not significantly different from that observed in the single infection. Our data indicate an alternation in replicative dominance in co-infection: HBV can suppress HCV replication to undetectable levels, whereas HCV may reduce but does not abrogate the replication capacity of HBV. Furthermore, in the cases of HCV dominance, circulating HBV genomes did not have a significant effect on the viral heterogeneity of HCV.


Assuntos
Hepacivirus/genética , Hepatite B/virologia , Hepatite C/virologia , Adulto , Idoso , Sequência de Aminoácidos , Doença Crônica , DNA Viral/sangue , Feminino , Variação Genética , Hepacivirus/isolamento & purificação , Hepatite B/sangue , Hepatite B/complicações , Vírus da Hepatite B/isolamento & purificação , Hepatite C/sangue , Hepatite C/complicações , Humanos , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Estrutura Terciária de Proteína , RNA Viral/sangue , Alinhamento de Sequência , Proteínas não Estruturais Virais/genética , Proteínas Virais/genética
5.
J Viral Hepat ; 8(3): 194-201, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11380797

RESUMO

Current evidence suggests that increased expression of Th1-associated cytokines is important for immune-mediated eradication of hepatitis C infection, while an increase in Th2-associated cytokines is associated with persistence of infection. In this study we evaluated the effects of thymosin-alpha1 (TA1), a naturally occurring thymic peptide, and interferon-alpha (IFN-alpha) on cytokine production in peripheral blood mononuclear cells from untreated patients with chronic hepatitis C. We examined the effect of incubation with TA1, IFN-alpha, or both, on production of Th1-associated cytokines (IL-2, IFN-gamma), Th2-associated cytokines (IL-4, IL-10), and synthesis of the antiviral protein 2',5'-oligoadenylate synthetase. TA1 treatment induced a significant increase in production of IL-2 and 2',5'-oligoadenylate synthetase. Smaller increases were also seen after treatment with IFN-alpha, while incubation with TA1 and IFN-alpha together led to an additive or synergistic effect. Incubation with TA1 resulted in a decrease in IL-4 and IL-10, whereas IFN-alpha increased these cytokines. The addition of TA1 to IFN-alpha significantly reversed this IFN-alpha-induced increase. Hence, TA1 treatment could benefit patients with hepatitis C infection by increasing the Th1-type response, fundamental for sustained clearance of hepatitis C; and by decreasing the Th2-type response, associated with persistence of viraemia.


Assuntos
Citocinas/biossíntese , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/farmacologia , Timosina/farmacologia , 2',5'-Oligoadenilato Sintetase/análise , 2',5'-Oligoadenilato Sintetase/biossíntese , 2',5'-Oligoadenilato Sintetase/sangue , Adjuvantes Imunológicos/farmacologia , Adulto , Antivirais/farmacologia , Células Cultivadas , Concanavalina A/farmacologia , Citocinas/análise , Feminino , Hepatite C Crônica/sangue , Hepatite C Crônica/imunologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Timalfasina , Timosina/análogos & derivados
6.
Antiviral Res ; 49(2): 75-81, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11248360

RESUMO

BACKGROUND AND AIMS: Interferon-alpha treatment has been the treatment of choice for chronic hepatitis with unpredictable results. Recently, Lamivudine has been licensed for use against HBV infection with good results. Unfortunately, recurrence of viremia after lamivudine withdrawal is common and prolonged treatment can induce the emergence of resistant mutant strains. It has been shown that vitamin E can increase the host immune response, and this may provide protection against infectious diseases. METHODS: We evaluated vitamin E supplementation as therapy for chronic hepatitis B in a pilot study including 32 patients. Patients were randomly allocated to receive vitamin E at the dose of 300 mg twice daily for 3 months (15 patients) or no treatment (17 patients). They were seen monthly during the first 3 months and thereafter quarterly for additional 12 months. RESULTS: The two groups were comparable at enrollment. At the end of the study period, alanine aminotransferase (ALT) normalization was observed in 7 (47%) patients in vitamin E group and only in 1 (6%) of the controls (P=0.011); HBV-DNA negativization was observed in 8 (53%) patients in the vitamin E group as compared to 3 (18%) in the control group, respectively (P=0.039). A complete response (normal ALT and negative HBV-DNA) was obtained in 7 (47%) patients taking vitamin E and in none of the controls (P=0.0019). CONCLUSION: Vitamin E supplementation might be effective in the treatment of chronic hepatitis B.


Assuntos
Hepatite B Crônica/tratamento farmacológico , Vitamina E/uso terapêutico , Adulto , Alanina Transaminase/sangue , DNA Viral/sangue , Feminino , Vírus da Hepatite B/isolamento & purificação , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Resultado do Tratamento
7.
Hepatology ; 32(5): 1145-53, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11050068

RESUMO

Lamivudine has been shown to be effective in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B, but its long-term efficacy and the rate of resistant mutations in patients with HBeAg-negative chronic hepatitis B is less clear. Twenty-nine patients with HBeAg-negative chronic hepatitis B, who have received lamivudine for at least 1 year were studied to determine the antiviral response, the rate and pattern of lamivudine-resistant mutations, and the effect of lamivudine-resistant mutations on HBeAg status. The mean duration of treatment was 21 +/- 7 months. Before treatment, core promoter variant was detected in 16 (55%) patients and precore stop codon variant in 18 (62%) patients. Serum hepatitis B virus (HBV) DNA was detected by solution hybridization assay in 62%, 4%, and 24% and by polymerase chain reaction (PCR) assay in 100%, 31%, and 40% at months 0, 6, and 24, respectively. The cumulative rates of detection of lamivudine-resistant mutations after 1 and 2 years of treatment were 10% and 56%, respectively. In addition to the duration of treatment, core promoter mutation was associated with the selection of lamivudine-resistant mutants. Three patients with lamivudine-resistant mutations had reversion of the precore stop codon mutation; in 2 patients this was accompanied by the reappearance of HBeAg. We found that lamivudine-resistant mutants were detected at similar rates in patients with HBeAg-negative as in patients with HBeAg-positive chronic hepatitis B. Additional changes in other parts of the HBV genome may restore the replication fitness of lamivudine-resistant mutants.


Assuntos
Produtos do Gene pol/genética , Antígenos E da Hepatite B/análise , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/genética , Lamivudina/uso terapêutico , Mutação , Inibidores da Transcriptase Reversa/uso terapêutico , Adulto , Idoso , Estudos de Coortes , Resistência Microbiana a Medicamentos/genética , Feminino , Genótipo , Vírus da Hepatite B/genética , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Proteínas do Core Viral/genética
8.
J Med Virol ; 62(1): 25-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10935984

RESUMO

Human cytomegalovirus (CMV) is an ubiquitous pathogen that can cause severe and often fatal infections in immunocompromised patients. Patients with cirrhosis often show various degrees of impaired cellular immunity that could lead to acute CMV reactivation. The aim of the present study was to determine whether laboratory findings of active CMV infections are common in patients with cirrhosis. Fifty-five patients with cirrhosis were studied for acute CMV infection by virological (antigenemia and quantitative polymerase chain reaction in polymorphonuclear leukocytes) and serological (detection of anti-CMV IgM by immunoblot) methods. The same tests were carried out on 50 blood donors and on 20 chronic hepatitis patients, considered as control populations. Acute or recent CMV infection had occurred in 31 (56%) of 55 patients with cirrhosis, whereas only 1 out of 20 (5%) patients with chronic non-cirrhotic liver disease and none of the 50 blood donors had laboratory signs of active CMV infection. The difference between patients with cirrhosis and the control groups was significant (P < 0.001, chi(2) test). CMV in patients with cirrhosis was not related to age, gender, hepatitis C virus infection or hepatocellular carcinoma. There was no significant correlation between impairment of liver function and the presence of active CMV infection. Patients with cirrhosis should be considered at risk for CMV infection, that seems to be mild and asymptomatic.


Assuntos
Antígenos Virais/sangue , Infecções por Citomegalovirus/diagnóstico , Cirrose Hepática/virologia , Doença Aguda , Adulto , Idoso , Alanina Transaminase/análise , Anticorpos Monoclonais , Aspartato Aminotransferases/análise , Bilirrubina/análise , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/imunologia , DNA Viral/sangue , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Fígado/enzimologia , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Risco , Testes Sorológicos
9.
Cytokine ; 12(6): 815-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10843771

RESUMO

In the present study, high levels of CD30s, a glycoprotein preferentially expressed and released by T lymphocytes producing Th(2)-type cytokines, were seen in the sera of patients with chronic hepatitis C, and a correlation with histological activity of the disease was found. CD30s levels were assayed in the sera of 29 HCV RNA-positive patients with histologically proven chronic active hepatitis and in 30 healthy blood donors. Thirteen of 29 (45%) HCV patients had CD30s serum levels above the normal range (>20 U/ml). Mean CD30s serum levels were significantly higher in HCV patients than in controls (P<0.0005). A positive correlation was found between serum CD30s levels and both the histological activity index (r=0.59, P=0.001) and ALT serum levels (r=0.5; P=0.006). The raised CD30s level found in more severe HCV liver disease indirectly suggests activation and expansion of Th(2)cells. CD30s levels could represent a useful surrogate marker of activity in chronic HCV infections.


Assuntos
Antígenos CD/sangue , Biomarcadores/sangue , Hepatite C Crônica/diagnóstico , Hepatite/sangue , Antígeno Ki-1/sangue , Adulto , Idoso , Alanina Transaminase/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite/etiologia , Hepatite/imunologia , Hepatite C Crônica/sangue , Hepatite C Crônica/imunologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Análise de Regressão
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