Quantification of Hepatitis C Virus in Human Liver and Serum Samples by Using LightCycler Reverse Transcriptase PCR

Diagnosis and clinical management of people infected with hepatitis C virus (HCV) relies on results from a combination of serological and virological tests. The aim of this study was to compare the performance of dried plasma spots (DPS), prepared using the cobas® Plasma Separation Card (PSC), to plasma and serum from venipuncture, for HCV diagnosis. We carried out a prospective study using DPS and paired plasma or serum samples. Serum and DPS samples were analyzed by immunoassay using Elecsys® Anti-HCV II (Roche). Plasma and DPS samples were analyzed using the cobas® HCV viral load and cobas® HCV genotyping tests (Roche). All DPS samples that had high anti-HCV antibody titers in serum were also antibody-positive, as were five of eight samples with moderate titers. Eight samples with low titers in serum were negative with DPS. Among 80 samples with plasma HCV viral loads between 61.5 and 2.2 × 108 IU/mL, 74 were RNA-positive in DPS. The mean viral load difference between plasma and DPS was 2.65 log10 IU/mL. The performance of DPS for detection of serological and virological markers of hepatitis C virus infection was comparable to that of the conventional specimen types. However, the limits of detection were higher for DPS.

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Genetic diversity and evolution of hepatitis C virus – 15 years on

Journal of General Virology ◽

10.1099/vir.0.80401-0 ◽

2004 ◽

Vol 85 (11) ◽

pp. 3173-3188 ◽

Cited By ~ 564

Author(s):

Peter Simmonds

Keyword(s):

Genetic Diversity ◽

Hepatitis C Virus ◽

Hepatitis C ◽

Human Liver ◽

Large Population ◽

Sequence Divergence ◽

Selection Pressures ◽

Host Interactions ◽

Persistent Viruses ◽

The Face

In the 15 years since the discovery of hepatitis C virus (HCV), much has been learned about its role as a major causative agent of human liver disease and its ability to persist in the face of host-cell defences and the immune system. This review describes what is known about the diversity of HCV, the current classification of HCV genotypes within the family Flaviviridae and how this genetic diversity contributes to its pathogenesis. On one hand, diversification of HCV has been constrained by its intimate adaptation to its host. Despite the >30 % nucleotide sequence divergence between genotypes, HCV variants nevertheless remain remarkably similar in their transmission dynamics, persistence and disease development. Nowhere is this more evident than in the evolutionary conservation of numerous evasion methods to counteract the cell's innate antiviral defence pathways; this series of highly complex virus–host interactions may represent key components in establishing its ‘ecological niche’ in the human liver. On the other hand, the mutability and large population size of HCV enables it to respond very rapidly to new selection pressures, manifested by immune-driven changes in T- and B-cell epitopes that are encountered on transmission between individuals with different antigen-recognition repertoires. If human immunodeficiency virus type 1 is a precedent, future therapies that target virus protease or polymerase enzymes may also select very rapidly for antiviral-resistant mutants. These contrasting aspects of conservatism and adaptability provide a fascinating paradigm in which to explore the complex selection pressures that underlie the evolution of HCV and other persistent viruses.

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Prospective study of hepatitis C virus infection in hemodialysis patients by monthly analysis of HCV RNA and antibodies

Canadian Journal of Microbiology ◽

10.1139/w03-065 ◽

2003 ◽

Vol 49 (8) ◽

pp. 503-507 ◽

Cited By ~ 25

Author(s):

Regina Moreira ◽

João Renato Rebello Pinho ◽

Jorge Fares ◽

Isabel Takano Oba ◽

Maria Regina Cardoso ◽

...

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Hemodialysis Patients ◽

Hcv Infection ◽

Hcv Rna ◽

Hepatitis C Virus Infection ◽

Serum Samples ◽

Hcv Genotypes ◽

High Prevalence ◽

Time Required

The aims of this study were to (i) evaluate the prevalence and the incidence of hepatitis C virus (HCV) infection in hemodialysis patients in two different centers in São Paulo (Brazil), (ii) determine the time required to detect HCV infection among these patients by serology or PCR, (iii) establish the importance of alanine aminotransferase determination as a marker of HCV infection, and (iv) identify the HCV genotypes in this population. Serum samples were collected monthly for 1 year from 281 patients admitted to hospital for hemodialysis. Out of 281 patients, 41 patients (14.6%) were HCV positive; six patients seroconverted during this study (incidence = 3.1/1000 person-month). In 1.8% (5/281) of cases, RNA was detected before the appearance of antibodies (up to 5 months), and in 1.1% (3/281) of cases, RNA was the unique marker of HCV infection. The genotypes found were 1a, 1b, 3a, and 4a. The presence of genotype 4a is noteworthy, since it is a rare genotype in Brazil. These data pointed out the high prevalence and incidence of HCV infection at hemodialysis centers in Brazil and showed that routine PCR is fundamental for improving the detection of HCV carriers among patients undergoing hemodialysis.Key words: HCV genotypes, hemodialysis, hepatitis C, PCR, prevalence, incidence.

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