Therapy For Hepatitis C Virus Infection Research Articles

Children with hepatitis C

An estimated 240,000 children in the United States have antibody to hepatitis C virus (HCV) and 68,000 to 100,000 are chronically infected with HCV. Acute HCV infection is rarely recognized in children outside of special circumstances such as a known exposure from an HCV-infected mother or after blood transfusion. Most chronically infected children are asymptomatic and have normal or only mildly abnormal alanine aminotransferase levels. Although the natural history of HCV infection acquired in childhood seems benign in the majority of instances, the infection takes an aggressive course in a proportion of cases leading to cirrhosis and end-stage liver disease during childhood; the factors responsible for a more aggressive course are unidentified. An optimal approach to management of hepatitis C in children would be prevention, particularly of perinatal transmission, which is now the major cause of new cases of hepatitis C in children. Obstetrical factors may be important determinants of transmission, which, if confirmed, should lead to changes in the care of infected women. Therapy of HCV infection in children is also not well defined. There have been no large randomized, controlled trials of therapy in children with chronic hepatitis C. Small heterogeneous studies of interferon monotherapy have reported sustained virological response rates of 35% to 40%. There are few data regarding the use of combination therapy with interferon and ribavirin in children and no information on the use of peginterferon. Clearly, there are important needs for future epidemiologic and clinical research on hepatitis C in childhood. (Hepatology 2002;36:S173-S178).

Children with hepatitis C.

An estimated 240,000 children in the United States have antibody to hepatitis C virus (HCV) and 68,000 to 100,000 are chronically infected with HCV. Acute HCV infection is rarely recognized in children outside of special circumstances such as a known exposure from an HCV-infected mother or after blood transfusion. Most chronically infected children are asymptomatic and have normal or only mildly abnormal alanine aminotransferase levels. Although the natural history of HCV infection acquired in childhood seems benign in the majority of instances, the infection takes an aggressive course in a proportion of cases leading to cirrhosis and end-stage liver disease during childhood; the factors responsible for a more aggressive course are unidentified. An optimal approach to management of hepatitis C in children would be prevention, particularly of perinatal transmission, which is now the major cause of new cases of hepatitis C in children. Obstetrical factors may be important determinants of transmission, which, if confirmed, should lead to changes in the care of infected women. Therapy of HCV infection in children is also not well defined. There have been no large randomized, controlled trials of therapy in children with chronic hepatitis C. Small heterogeneous studies of interferon monotherapy have reported sustained virological response rates of 35% to 40%. There are few data regarding the use of combination therapy with interferon and ribavirin in children and no information on the use of peginterferon. Clearly, there are important needs for future epidemiologic and clinical research on hepatitis C in childhood.

The natural history and antiviral treatment of hepatitis C in haemophilia.

People with haemophilia who received non-virucidally treated large-pool clotting factor before 1986 were infected with hepatitis C virus (HCV), previously referred to as non-A, non-B hepatitis. Approximately one-tenth of patients have been shown to clear infection naturally and shown persistently negative HCV PCR. Patients have been infected with genotypes 1, 2 and 3 reflecting the plasma donors in Northern Europe and the United States. Several studies have shown that HCV mono-infection has a very slow progression. Co-infection with human immunodeficiency virus (HIV), however, can hasten the progression to cirrhosis and liver failure. Genotype 1 and older age at first infection also increase the progression rate. Candidates with detectable HCV RNA are candidates for therapy. The combination of standard interferon-alpha and ribavirin doubles the effectiveness of interferon-alpha alone and is the current standard of care for the treatment of chronic hepatitis C. The duration of therapy depends on the genotype and level of viraemia. Patients with genotypes 2 or 3 should have 6 months' therapy while those with genotype 1 and > 2 million copies mL-1 should have 1 year of therapy. Pegylated interferon is an emerging therapy. Patients co-infected with HIV, in whom treatment has stabilized the HIV infection, may be able to tolerate therapy for HCV infection. Liver transplantation is indicated for patients with haemophilia who have decompensated hepatitis C infection.

Hepatitis c virus (HCV) and human immunodeficiency virus type 1 (HIV-1) infections in alcoholics

Approximately 400,000 individuals in the United States are co-infected with hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) and it is likely that almost one in two of these subjects consumes alcohol. The majority of these patients suffer an accelerated course of liver disease as manifested by the onset of cirrhosis within 5 to 10 years of developing HCV infection, as well as an increased risk of developing hepatocellular carcinoma (HCC). It is thought that chronic alcohol abuse mediates liver damage as a result of increased production of free radicals and proinflammatory cytokines. In the setting of chronic HCV infection, alcohol ingestion has an additional effect of diminishing immune clearance and increasing viral burden to hasten the onset of cirrhosis and HCC. Likewise, chronic HCV and HIV-1 co-infection results in a net increase in HCV burden; higher prevalence rates of HCV transmission to sexual partners and offspring, as well as an accelerated progression to end stage liver disease as compared to individuals with HCV infection alone. Thus, the synergistic effects of alcohol abuse and HIV-1 greatly impact on the morbidity and mortality for patients with HCV coinfection. Ultimately, this cumulative disease process will require far more aggressive management with abstinence and counseling for alcohol abuse; highly active antiretroviral therapy (HAART) for HIV infection and combination anti-viral therapy for HCV infection to stem the rapid progression to end stage liver disease.

Hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) infections in alcoholics.

Approximately 400,000 individuals in the United States are co-infected with hepatitis C virus (HCV) and human immunodeficiency virus type 1 (HIV-1) and it is likely that almost one in two of these subjects consumes alcohol. The majority of these patients suffer an accelerated course of liver disease as manifested by the onset of cirrhosis within 5 to 10 years of developing HCV infection, as well as an increased risk of developing hepatocellular carcinoma (HCC). It is thought that chronic alcohol abuse mediates liver damage as a result of increased production of free radicals and proinflammatory cytokines. In the setting of chronic HCV infection, alcohol ingestion has an additional effect of diminishing immune clearance and increasing viral burden to hasten the onset of cirrhosis and HCC. Likewise, chronic HCV and HIV-1 co-infection results in a net increase in HCV burden; higher prevalence rates of HCV transmission to sexual partners and offspring, as well as an accelerated progression to end stage liver disease as compared to individuals with HCV infection alone. Thus, the synergistic effects of alcohol abuse and HIV-1 greatly impact on the morbidity and mortality for patients with HCV coinfection. Ultimately, this cumulative disease process will require far more aggressive management with abstinence and counseling for alcohol abuse; highly active antiretroviral therapy (HAART) for HIV infection and combination anti-viral therapy for HCV infection to stem the rapid progression to end stage liver disease.

Cross‐reactivity and clinical impact of the antibody response to hepatitis C virus second envelope glycoprotein (E2)

The genotype of hepatitis C virus (HCV) can profoundly affect the success of antiviral therapy for HCV infection. A possible contributing factor is a varied immune response elicited by infection with different HCV genotypes. In this study, full-length E2 proteins of HCV genotypes 1a, 1b, 2a, and 2b were used to determine the fraction of the humoral immune response to HCV E2 that is genotype specific. Greater than 90% of all infected individuals had serum antibodies to the four E2 proteins. Overall, individuals infected with genotype 1a or 1b were characterized by variable immune responses to HCV E2 with relatively high amounts of cross-reactivity with other E2 proteins. Individuals infected with genotype 2a or 2b exhibited a strong preferential reactivity to genotype 2a and 2b E2 proteins. Individuals with elevated titers to HCV E2 were more likely to be infected with genotype 2a and had a significantly lower median viral load. These findings indicate that the antibody response to HCV E2 is affected by the genotype of the virus and that induction of a strong humoral immune response to HCV E2 may contribute to a decreased viral load.

Management of the HIV-HCV coinfected patient

See article on page 694 Parenterally acquired infection by human immunodeficiency virus (HIV) is frequently associated with chronic hepatitis C virus (HCV) infection. Last year, the European Association for the...

Evaluation of factors controlling glucose tolerance in patients with HCV infection before and after 4 months therapy with interferon-alpha.

Epidemiological data suggest that chronic hepatitis C virus (HCV) infection may contribute to the development of diabetes mellitus. Therapy of HCV infection with recombinant interferon-alpha (r-IFN-alpha) can also impair of glucose metabolism. To investigate the impact of HCV infection and the therapy with r-IFN-alpha on glucose metabolism we measured insulin sensitivity, glucose effectiveness, and first and second phase insulin secretion, using the minimal modelling analysis of frequently sampled intravenous glucose tolerance tests in 13 nondiabetic patients with HCV-induced liver disease before and after therapy with r-INF-alpha (6 x 106 U, subcutaneously, three times a week over 4 months). Liver biopsy was performed to evaluate and score liver fibrosis as a marker of HCV-induced cell injury. Insulin sensitivity (r = - 0.59, P < 0.05) and first phase insulin secretion (r = - 0.66, P < 0.03) were negatively related to the fibrosis score. Insulin sensitivity rose from 1.96 (SEM 0.37, n = 8) to 5.69 (SEM 0.99, n = 8) 10-4 min-1 per microU mL-1 (P < 0.01) in responders and from 2.51 (SEM 0.61, n = 5) to 6.95 (SEM 1.99, n = 5) in nonresponders after 4 months r-INF-alpha therapy. Fasting free fatty acids decreased significantly to about 50% (P < 0.01) in patients with and without therapy response after 4 months, whereas first phase insulin secretion did not change. HCV-induced liver injury is related to the deterioration of insulin sensitivity and first phase insulin response, thus impairing glucose homeostasis in these HCV-infected patients. The administration of r-INF-alpha three times a week over 4 months is not associated with an impairment of glucose homeostasis.

Glomerulonephritis associated with hepatitis c virus infection

We report 4 patients with glomerulonephritis (GN) associated with hepatitis C virus (HCV) infection seen between August 1993 and July 1996. Two of them were male and median age was 41 years. Anti-HCV was detected by enzyme-immunoassay and HCV-RNA by PCR. Serum cryoglobulins, 24-hour proteinuria, and erythrocyte dismorphism were also determined. Viremia, cryoglobulinemia, hematuria and proteinuria were observed in all patients. Liver biopsies revealed inflammatory activity in 3 cases, and renal biopsies revealed membranoproliferative glomerulonephritis in 3 patients and mesangial proliferative glomerulonephritis in 1 patient. Two patients are on specific therapy for HCV infection (IFN in combination with ribavirin) and have presented clinical and laboratory improvement. The occurrence of active liver disease and viremia concurrent with urinary alterations suggests viral involvement in renal disease, a conclusion supported by the by improvement of urinary alterations observed after treatment for HCV. We conclude that the search for viral markers in patients with GN is important since their detection could change the therapeutic approach.

Establishment and Characterization of NS3 Protein-Specific T-Cell Clones from a Patient with Chronic Hepatitis C

Our previous study showed dominant proliferative response of peripheral mononuclear cells to hepatitis C virus (HCV) nonstructural (NS-3) (T9, from aa 1188 to 1493) in chronically infected patients. Six T9-specific T-cell clones derived in an HCV patient were established and studied for the antigen specificity and the ability of augmentation of in vitro antibody production. All these cloned T-cell lines responded exclusively to T9 antigen and could help autologous B cells in producing anti-T9 antibody in vitro. Cytokine mRNAs of these T cells was detected by polymerase chain reaction and predominant IL-2 and IFN-γ production was noted. In addition, further elucidation of T-cell antigenic determinant and MHC restriction suggested that these T-cell clones recognized at least two different T-cell antigenic determinants within the NS-3 region in an HLA DQ2-restricted manner. We believe characterization of HCV-specific T-cell responses, especially T-cell epitope mapping and cytokine production pattern, may shed light on further understanding the pathogenic mechanism and designing therapy for HCV infection.