RESUMEN
The role of hepatitis C virus (HCV)-specific CD4+ T cells in recurrent HCV infection after orthotopic liver transplantation (OLTx) is unclear. In parallel, 73 intrahepatic and 73 blood-derived T cell lines were established from 34 patients. At a single cell level, virus-specific interferon (IFN)-gamma production to various HCV proteins was determined by ELISPOT assay: 45 (62%) of 73 liver- or blood-derived T cell lines produced IFN-gamma in response to one of the HCV antigens. HCV specificity was detected mainly in the liver (47% vs. 23% in the blood; P<.05, chi(2) test) and was detectable earlier (< or =6 months) significantly more often than later (>6 months) after OLTx (78% vs 49%; P<.05, chi(2) test). Histology, histologic activity index, liver enzymes, and virus load did not correlate with the occurrence of HCV-specific CD4+ T cells. Despite strong immunosuppressive treatment, OLTx recipients can develop an early, multispecific, preferentially intrahepatic CD4+ T cell response that decreases over time, making it a potential candidate target for novel therapeutic approaches in the transplant setting.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Hepacivirus/inmunología , Hepatitis C/inmunología , Trasplante de Hígado/inmunología , Formación de Anticuerpos , Biopsia , Técnicas de Cultivo de Célula , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Femenino , Genotipo , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Hepacivirus/genética , Hepatitis C/cirugía , Anticuerpos contra la Hepatitis C/análisis , Anticuerpos contra la Hepatitis C/sangre , Humanos , Interferón gamma/biosíntesis , Hígado/inmunología , Fallo Hepático/etiología , Fallo Hepático/cirugía , Pruebas de Función Hepática , Trasplante de Hígado/patología , Trasplante de Hígado/fisiología , Masculino , Persona de Mediana Edad , ARN Viral/análisis , Recurrencia , Factores de TiempoRESUMEN
Virus-specific CD4(+) T-cell response at the site of inflammation is believed to play a decisive role for the course of viral disease. In hepatitis C virus (HCV) infection, the majority of studies focused on the peripheral blood T-cell response. In this study we analyzed intrahepatic virus-specific CD4(+) T-cell response and compared this with that in the peripheral blood. Liver and blood-derived T-cell lines were studied in 36 patients (18 with chronic hepatitis C and 18 with HCV-associated cirrhosis). Virus-specific interferon gamma (IFN-gamma) production at a single cell level to various HCV-proteins (core, nonstructural [NS] 3/4, NS5) were determined by enzyme-linked immunospot (ELIspot). Phenotyping was done by fluorescent-activated cell sorter analysis. In approximately half (16 of 36 [44%]) of intrahepatic T-cell lines a significant number of IFN-gamma spots were observed, whereas this was the case in only 19% (7 of 36 T-cell lines) in the blood. In relative terms, core and nonstructural proteins were recognized with the same frequency in both compartments, but HCV-specificity was significantly more often detected in liver tissue compared with the blood. Hepatitis activity index, viral load, and alanine transaminase levels did not correlate with the detection of HCV-specific CD4(+) T cells. All T-cell lines were dominated by CD4(+) T cells. In conclusion, HCV-specific CD4(+) T cells are multispecific, compartmentalize to the liver, and produce IFN-gamma. We speculate that our data would support the concept of compartmentalization of specific T cells at the site of inflammation and that a low frequency of specific T cells is associated with failure to clear the virus and a chronic course of disease.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Epítopos/inmunología , Hepacivirus/inmunología , Interferón gamma/biosíntesis , Hígado/inmunología , Hígado/metabolismo , Adulto , Biomarcadores/análisis , Células Sanguíneas/inmunología , Células Sanguíneas/metabolismo , Células Cultivadas , Femenino , Hepatitis C Crónica/sangre , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/patología , Humanos , Hígado/patología , Cirrosis Hepática/sangre , Cirrosis Hepática/inmunología , Cirrosis Hepática/patología , Cirrosis Hepática/virología , Masculino , Persona de Mediana EdadRESUMEN
Orthotopic liver transplantation (OLT) is a successful treatment in patients with hepatitis C virus (HCV)-associated end-stage liver disease worldwide. T lymphocytes and their cytokines are believed to have a pivotal role in the defense against HCV and in allograft rejection. An immunosuppressive drug regimen may cause a cytokine imbalance toward a T helper (TH) cell type 2 profile that is associated with the persistence of infection and acceptance of the graft. The aim of this study is to assess whether cytokine imbalances toward a TH1- or TH2-type response may have a role in recurrent HCV infection and rejection after OLT. Twenty-one intrahepatic T-cell lines of 15 patients with recurrent HCV infection after OLT (group A) and 15 lines of 11 patients with rejection (group B) were studied. Both patient groups had received liver allografts because of HCV-associated end-stage liver disease. Patients with HCV-induced liver disease who did not undergo OLT served as controls: 17 patients with chronic hepatitis C (CH-C) and 8 patients with cirrhosis. At the time of liver biopsy, 14 blood-derived T-cell lines of 12 patients with recurrent HCV infection, 7 of 10 patients with rejection, and 18 of 18 control patients were also investigated. Regardless of the underlying disease (recurrent HCV infection, rejection, HCV-induced hepatitis, and cirrhosis), all liver tissue-derived T-cell lines produced interferon-gamma; some additionally produced interleukin-4 (IL-4), but none produced IL-10, indicating that the TH0/1 cytokine profile dominates. T-cell lines showing a TH1 cytokine profile derived from intrahepatic T cells could be established significantly more often in recurrent HCV infection and rejection than in controls with CH-C (Fisher's exact test, P <.05). The cytokine profile of intrahepatic T cells did not differ from that obtained in peripheral blood. TH0/1 cytokine profile dominates the intrahepatic and blood-derived immune response in recurrent HCV infection and rejection after OLT regardless of the mode of immunosuppression. The lymphokine profile of immunocompromised patients with recurrent HCV infection or rejection does not differ principally from that of patients with HCV-induced hepatitis and cirrhosis, but seems to show a TH1 profile significantly more often.