HCV

HCV

Table of Contents

Chapter 13

General Introduction3

Chapter 27

HCV genotyping and the estimation of the viral load7

Chapter 322

Sequence Analysis of the ISDR of Isolates from Patients Infected with HCV Genotype 1b treated with IFN-a and RBV22

Chapter 433

Proteomics approaches to elucidating the HCV infection33

Chapter 536

Discussion and Conclusion36

References50

Chapter 1

General Introduction

Aims of the research

To identify patients chronically infected with hepatitis C virus who are about to start combination therapy with pegylated interferon alpha and ribavirin.

To identify individuals infected with genotype 1b by means of TRUGENE HCV genotyping methodology.

To collect serum samples from these patients at regular intervals before, during and after treatment.

To determine viral load by means of real-time RT-PCR technique developed in-house.

To sequence NS5A region of viral isolates and identify any temporal changes in the ISDR region and differences that may be seen between sustained responders, transient responders and non-responders.

To identify the potential biomarkers, which might indicate either responsiveness or resistance to treatment of chronic HCV with peg-IFN plus RBV, in the first stages of ongoing analysis for the plasma proteome?

Background

The hepatitis C virus (HCV) was initially isolated from the serum of patients with so-called Non-A Non-B hepatitis (Choo et al, 1989). The cloning of the non-A non-B agent identified it as a positive stranded RNA virus and demonstrated this to be the cause of 90 % of Non-A Non-B hepatitis in the USA (Chen & Morgan 2006).

HCV is a member of the Flaviviridae family and infects approximately 200 million people worldwide (Dhillon et al 1995). More than 50 % of those infected, possibly as many as 90 %, become carriers; and at least 20 % may be at risk of developing cirrhosis and liver cancer (Moradpour et al, 2001).

Since the clinical features of HCV infection are similar to those induced by other hepatitis viruses, diagnosis cannot be made on the basis of symptoms and signs alone. Although acute HCV may be symptomatic (presenting with jaundice and elevated transaminases), the majority of cases are asymptomatic and patients may present years or decades later with advanced liver disease (chronic active hepatitis, cirrhosis or hepatocellular carcinoma). A minority of patients with acute HCV infection show spontaneous resolution, but the majority (70 % to 85 %) develop chronic infection (Figure 1-1.1). In addition, it has been estimated that HCV accounts for 27 % of cirrhosis and 25 % of HCC worldwide. (Alter, 1997). In this chapter, the HCV is discussed from the standpoint of its epidemiology, prevention and management (sections 1.2-1.5); its structure and infectivity (sections 1.6-1.8); and its impact on patients, together with the forms and effects of treatment (sections 1.9- 1-11), concluding with a statement of the aims of the research.

Epidemiology

Infection with HCV remains a significant international healthcare problem. Various at-risk groups have been identified, including intravenous drug users, blood donors and patients with HIV infection. Other risk factors associated with the transmission of HCV include healthcare professionals, laboratory workers and people of relatively low socioeconomic status.

Transmission, Prevention and Clinical Management

The sexual transmission of hepatitis C and the prevalence of hepatitis C ...