Hepatitis C: progress and problems

Abstract

The hepatitis C virus (HCV), a single-stranded RNA virus, is the major cause of posttransfusion hepatitis. HCV isolates differ in nucleotide and amino acid sequences. Nucleotide changes are concentrated in hypervariable regions and may be related to immune selection. In most immunocompetent persons, HCV infection is diagnosed serologically, using antigens from conserved regions. Amplification of RNA may be necessary to detect infection in immunosuppressed patients. Transmission by known parenteral routes is frequent; other means of spread are less common and may represent inapparent, percutaneous dissemination. Infection can lead to classical acute hepatitis, but most infected persons have no history of acute disease. Once infected, most individuals apparently remain carriers of the virus, with varying degrees of hepatocyte damage and fibrosis ensuing. Chronic hepatitis may lead to cirrhosis and hepatocellular carcinoma. However, disease progression varies widely, from less than 2 years to cirrhosis in some patients to more than 30 years with only chronic hepatitis in others. Determinants important in deciding outcome are unknown. Alpha interferon, which results in sustained remission in selected patients, is the only available therapy. Long-term benefits from such therapy have not been demonstrated. Prevention of HCV infection by vaccination is likely to be challenging if ongoing viral mutation results in escape from neutralization and clearance.

Transgenic expression of hepatitis C virus structural proteins in the mouse

“…We rate of chronicity after HCV infection, with at least 70% of concluded that HCV structural proteins are not directly those infected developing chronic liver disease. 11 In addition cytopathic in this animal model. (HEPATOLOGY 1997;25: to the morbidity and mortality caused by chronic liver dys-1014-1021.)…”

Effect of interferon therapy on hepatitis C virus RNA in whole blood, plasma, and peripheral blood mononuclear cells

“…[1][2][3] Infection with HCV usually results in chronic active hepatitis, which may progress to cirrhosis. Currently, end-stage liver disease resulting from chronic HCV infection is a major reason for referral of patients for orthotopic liver transplantation in the United States.…”

“…6,7 Although the reasons responsible for relapse are unclear, variables such as length of treatment, HCV genotype, and histological evidence of inflammation and fibrosis at the start of therapy appear to correlate with treatment outcomes. 3,[8][9][10][11] Reverse-transcription (RT) polymerase chain reaction (PCR) techniques to detect HCV RNA during interferon therapy have been widely employed and are considered to be important for optimum management. 12,13 A high level of HCV RNA in serum before treatment is a poor prognostic sign for sustained response; unfortunately, clearance of virus from serum or plasma at the end of treatment as determined by qualitative RT-PCR test does not reliably predict a sustained response.…”

Evaluación de diferentes péptidos de la región estructural del virus de la hepatitis C

“…El virus de la hepatitis C (HCV) está cdmpuesto ensayos diagnósticos para la detección de por un genoma de ARN de cadena simple con anticuerpos a estevirus (3)(4)(5)(6). Sin embargo, se ha .sentido positivo de aproximadamente 9.500 observado que las zonas cercanas a la región nucleótidos 19.4 kilobases\.…”

“…La proteína estructural del núcleo (C) está altamente conservada y presenta una gran antigenicidad entre los diferentes aislamientos, de ahí la importancia de su incorporación en los Correspondencia: iqpeptidos@cie.sld.cu Recibido: 12/04/00; aceptado: 02/02/01 (3)(4)(5)(6).…”