RESUMO
INTRODUCTION: The mechanisms by which severe cholestatic hepatitis develops after liver transplantation are not fully understood. Reports on immunohistochemical distribution of hepatitis C virus (HCV) antigens are still scarce, but recently, HCV immunostaining was suggested for early diagnosis of cholestatic forms of recurrent hepatitis C in liver grafts. After purification, Rb246 pab anticore (aa1-68) yielded specific, granular cytoplasmic staining in hepatocytes. Signal amplification through the Envision-Alkaline Phosphatase System avoided endogenous biotin and peroxidase. AIMS/METHODS: Rb246 was applied to liver samples of explants of 12 transplant recipients, six with the most severe form of post-transplantation recurrence, severe cholestatic hepatitis (group 1) and six with mild recurrence (group 2). We also assessed immuno-reactivity at two time-points post-transplantation (median 4 and 22 months) in both groups. HCV-core Ag was semiquantified from 0 to 3+ in each time point. Serum HCV-RNA was also measured on the different time points by branched DNA. RESULTS: In the early post-transplant time point, one patient had a mild staining (1+), two patients had a moderate staining (2+) and the other three had no staining in group 1, compared with five patients with no staining (0) and one patient with mild staining (1+) in group 2. Late post-transplant liver samples were available in nine patients, and two out of four samples in group 1 showed a mild staining, compared with no staining patients in five patients in group 2. Strikingly, on the explant samples, HCV immunostaining was strongly positive in group 1, and mildly positive in group 2. Two out of five samples showed 3+ staining, and three samples showed 2+ staining in group 1; two out of five samples showed no staining, two samples showed 1+ staining and one sample showed 2+ staining in group 2. Serum HCV-RNA was significantly higher in group 1, on both time-points post-transplantation. HCV-core Ag was not directly associated with serum HCV-RNA on the different time points. CONCLUSION: These preliminary results suggest that strong HCV immunostaining in the explant is predictive of more severe disease recurrence.
Assuntos
Colestase Intra-Hepática/virologia , Hepacivirus/patogenicidade , Hepatite C/virologia , Transplante de Fígado , Complicações Pós-Operatórias , Colestase Intra-Hepática/patologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/patologia , Antígenos da Hepatite C/análise , Humanos , Técnicas Imunoenzimáticas , Fígado/química , Fígado/patologia , Fígado/virologia , Falência Hepática/cirurgia , Falência Hepática/virologia , RNA Viral/sangue , Recidiva , Proteínas do Core Viral/análiseRESUMO
OBJECTIVE: To assess the evolution of in vitro T cell response to hepatitis C virus (HCV) Core, E1, E2 and NS3 antigens in 10 patients with chronic hepatitis C, before, during and after a high dose interferon alpha (IFN-alpha) therapy, and to evaluate the influence of IFN-alpha on the in vivo and in vitro production of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). METHODS: T cell response to HCV antigens was evaluated by lymphoproliferation assays. In vivo and in vitro cytokine production was evaluated at weeks 0, 4, 8, and 12 of IFN-alpha therapy by enzyme immunoassays. RESULTS: In general, of all HCV antigens tested throughout the follow-up, those belonging to the Core region were the most immunostiumlatory. This observation was valid in IFN-alpha responders as well as IFN-alpha non-responders. The lymphoproliferative response to HCV antigens increased during IFN-alpha therapy. Serum levels of TNF-alpha were significantly increased in HCV patients, and six out of ten patients showed increased IFN-gamma serum levels. A significant decrease of IFN-gamma levels was observed during therapy and the same trend was seen for TNF-alpha. Mitogen-stimulated TNF-alpha and IFN-gamma production before therapy did not differ from that of normal controls, however, the cytokine production was reduced at week 4 of therapy, corresponding with a clinical improvement. A return to pretreatment values was observed after 8 weeks of therapy. CONCLUSIONS: a) Core antigens are the most immunostimulatory HCV antigens at the T cell level in chronic hepatitis C patients; b) High dose IFN-alpha therapy induces an increase in lymphoproliferative response to HCV antigens; c) Serum levels of TNF-alpha are increased in HCV patients; d) High dose IFN-alpha therapy induces a decrease in serum levels of IFN-gamma; e) High dose IFN-alpha therapy induces a transiently decreased mitogen-induced TNF-alpha and IFN-gamma production.
Assuntos
Antivirais/farmacologia , Antígenos da Hepatite C/fisiologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Fatores Imunológicos/farmacologia , Interferon-alfa/farmacologia , Interferon gama/biossíntese , Linfócitos T/fisiologia , Fator de Necrose Tumoral alfa/biossíntese , Adulto , Idoso , Antivirais/uso terapêutico , Células Cultivadas , Meios de Cultura , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Proteínas do Core ViralRESUMO
OBJECTIVE: To assess the evolution of in vitro T cell response to hepatitis C virus (HCV) Core, E1, E2 and NS3 antigens in 10 patients with chronic hepatitis C, before, during and after a high dose interferon alpha (IFN-alpha) therapy, and to evaluate the influence of IFN-alpha on the in vivo and in vitro production of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma). METHODS: T cell response to HCV antigens was evaluated by lymphoproliferation assays. In vivo and in vitro cytokine production was evaluated at weeks 0, 4, 8, and 12 of IFN-alpha therapy by enzyme immunoassays. RESULTS: In general, of all HCV antigens tested throughout the follow-up, those belonging to the Core region were the most immunostiumlatory. This observation was valid in IFN-alpha responders as well as IFN-alpha non-responders. The lymphoproliferative response to HCV antigens increased during IFN-alpha therapy. Serum levels of TNF-alpha were significantly increased in HCV patients, and six out of ten patients showed increased IFN-gamma serum levels. A significant decrease of IFN-gamma levels was observed during therapy and the same trend was seen for TNF-alpha. Mitogen-stimulated TNF-alpha and IFN-gamma production before therapy did not differ from that of normal controls, however, the cytokine production was reduced at week 4 of therapy, corresponding with a clinical improvement. A return to pretreatment values was observed after 8 weeks of therapy. CONCLUSIONS: a) Core antigens are the most immunostimulatory HCV antigens at the T cell level in chronic hepatitis C patients; b) High dose IFN-alpha therapy induces an increase in lymphoproliferative response to HCV antigens; c) Serum levels of TNF-alpha are increased in HCV patients; d) High dose IFN-alpha therapy induces a decrease in serum levels of IFN-gamma; e) High dose IFN-alpha therapy induces a transiently decreased mitogen-induced TNF-alpha and IFN-gamma production.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Antivirais , Linfócitos T , Interferon gama , Fator de Necrose Tumoral alfa , Interferon-alfa , Fatores Imunológicos , Antígenos da Hepatite C/fisiologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/imunologia , Antivirais , Interferon-alfa , Meios de Cultura , Fatores Imunológicos , Ativação Linfocitária , Células Cultivadas , Proteínas do Core ViralRESUMO
No presente estudo, avaliamos a importancia clinico-epidemiologica da genotipagem do VHC em 130 pacientes com diagnostico histologico de hepatite cronica C e sua influencia na resposta terapeutica sustentada. Nao se observou associacao entre os genotipos e os aspectos clinico-epidemiologicos como sexo, idade, vias de trasmissao, presenca ou nao de cirrose e tempo de infeccao. Dos 130 pacientes, 113 foram submetidos a tratamento com...