Résumé
BACKGROUND/AIMS: Quantitation of Hepatitis C Virus (HCV) RNA in serum is important for monitoring the response to interferon-alpha therapy in patients with chronic hepatitis C. Several commercial assays are recently available, but they are expensive and cannot be used as a gold standard. METHODS: An in-house competitive reverse transcription-polymerase chain reaction (cRT-PCR) was developed and validated. The procedure involves the construction of a mutant and wild type HCV RNA internal standard (IS), cRT-PCR, and colorimetric detection with DNA-ELISA. A standard curve was obtained and used for final HCV RNA quantitation. RESULTS: The standard curve was linear over the range of 1x104 to 5x107 copies/mL of the HCV RNA standard (r=0.976). This in-house cRT-PCR was comparable with the branched DNA (bDNA) assay (Quantiplex HCV 2.0, Chiron, USA) with positive correlation between the two tests (r=0.735). CONCLUSION: The quantitation of HCV RNA by in-house cRT-PCR and DNA ELISA was more sensitive and had wider range of detection compared to bDNA assay. This assay is useful for follow-up of HCV RNA concentration after interferon-alpha therapy.