Comparison of Serum Hepatitis C Virus RNA and Core Antigen Concentrations and Determination of Whether Levels Are Associated with Liver Histology or Affected by Specimen Storage Time

Abstract

An enzyme immunoassay has recently been developed for the hepatitis C virus (HCV) core antigen. To evaluate the possible association between core antigen and HCV RNA levels with regards to the change in liver histology over time as well as study the effect of duration of storage on viral load results, sequential sera were analyzed from 45 patients with chronic HCV infection who had undergone two or more liver biopsies. A relatively strong association was found between the core antigen and HCV RNA concentrations (r s ‫؍‬ 0.8), with a core antigen level of 1 pg/ml corresponding to approximately 1,000 IU/ml. All 42 sera with detectable HCV RNA at the time of the second biopsy had core antigen concentrations above 1 pg/ml, and the three sera without detectable HCV RNA had concentrations below 1 pg/ml. No association was found between HCV RNA or core antigen levels and the stage of fibrosis in biopsy samples, progression of fibrosis, necro-inflammatory grade, steatosis, genotype, alanine aminotransferase level, or alcohol consumption. A significant association was demonstrated between the storage time of the samples and both the HCV RNA and core antigen concentrations. The median log HCV RNA concentrations (international units/milliliter) were 3.92 for the sera obtained at the time of the first biopsy (median storage time, 13.0 years) and 4.41 for the sera obtained at the time of the second biopsy (median storage time, 6.6 years) compared to 5.96, the median for 102 different routine clinical patient samples.

Evaluation of Serum Lipid Profile in Turkish Patients with Chronic Hepatitis C

“…In contrast, in some studies in literature, it was stated that genotype 3a with steatosis was related with virus load amount but not related with other genotypes (16,17). In some studies it was stated that there wasn't any relation between virus load amount and hepatosteatosis (18). Results in our study is in harmony with this literature.…”

Design Options for Molecular Epidemiology Research within Cohort Studies

“…Benzo(a)pyrene-DNA adducts have been reported to be stable in samples stored for 10 months (34). However, levels of other markers, such as lipoprotein A, total and high-density lipoprotein cholesterol, triglycerides (35)(36)(37), HIV p24 antigen (38), free prostate-specific antigen (39), progesterone (40), estradiol (41), hepatitis virus C RNA concentrations (42), and salivary IgA (43), have been shown to change during sample storage. Additionally, for paraffin-embedded tissue sections, the reliability of immunohistochemical and fluorescence in situ hybridization assays for HER2 decline with storage time (44), as does antigenicity for tissue microarrays (45).…”

Benefit of Hepatitis C Virus Core Antigen Assay in Prediction of Therapeutic Response to Interferon and Ribavirin Combination Therapy

“…Methods for detecting viral antigens (Ag) were developed by applying a monoclonal antibody to the HCV core Ag (19,33,35); however, the assays have been insufficient for clinical application because of their low sensitivity and the requirement for complicated specimen pretreatment. An accurate and specific new HCV core Ag detection assay system (total HCV core Ag assay) (2) has recently been developed and is commercially available in European countries (trak-C assay) (7,20,24,25,31); it has a lower detection level limit of 1.5 pg/ml, which is equivalent to 20 KIU/ml. More recently, Lumipulse Ortho HCV Ag (Lumipulse-Ag), with a lower detection level limit of 50 fmol/liter (equivalent to 1.0 pg/ml), was developed in Japan (1,34).…”