A part of the hepatitis C virus (HCV) nonstructural protein 5A (NS5A) amino acid sequence, designated as an interferon (IFN)-sensitive determining region (ISDR), has been shown to be correlated with a response to IFN in Japanese patients. We have shown previously that the presence of NS5A antibodies (Abs) detected by the INNOLIA test (IL-NS5A Ab) is also correlated with a response to IFN. The aim of this study was to investigate, in a wide range of patients, the possible relationship within the NS5A protein between the sequence of ISDR and that used in the INNOLIA test designated as IL3R. Serum samples from 52 patients infected by HCV genotypes 1, 2, and 3 were analyzed before and after treatment. The patients were classified as nonresponders (NRs), responder-relapsers (RRs), or long-term responders (LTRs). We amplified the NS5A region for 42 patients using polymerase chain reaction (PCR), and these amplicons were sequenced directly. The 10 remaining patients were analyzed using PCR with mutation-specific primers. No correlation was found between the IL3R sequence of the HCV strains and the presence of the IL-NS5A Ab for all genotypes. However, for the subtype 1b, only 2 of 11 NR patients tested had an arginin in position 2218 within the ISDR versus 3 of 3 LTR and 10 of 13 RR patients. All patients with R-2218 had IL-NS5A Ab. For the genotype 1a, 2 of 2 LTR and 1 of 3 RR were mutated in position 2216-2218 in comparison to three NR sequences. For the genotype 3, no mutations were found in the region homologous to 1b-ISDR, but 4 of 5 LTR and RR patients had a mutation T-2161 to A or V versus 0 of 3 NR patients. A close correlation was found between arginin in position 2218 in ISDR, the presence of IL-NS5A Ab, and the response to IFN therapy for genotype 1b, but this association did not predict a long-term response. For genotype 3, a potential ISD mutation could be located at the codon 2161.
Human herpesvirus 8 (HHV-8) is a new virus which has been reported in Kaposi's sarcoma and some lymphoproliferative disorders such as Castleman's disease and body-cavity-based lymphoma. Because HHV-8 shares homology with Epstein-Barr virus (EBV), we searched for the presence of HHV-8 DNA sequences in various cutaneous T-and B-cell lymphoma by the polymerase chain reaction (PCR). Fortyseven HIV-negative patients with cutaneous lymphoma or large plaque parapsoriasis were enrolled in the study. For the detection of HHV-8 DNA sequences we used PCR followed by a hybridization with a digoxigenin-labelled probe and nested-PCR. HHV-8 DNA sequences could only be detected in a patient with large plaque parapsoriasis. Our study does not suggest any direct implication of HHV-8 in the pathogenesis of most cutaneous lymphoma. Serological studies will be helpful to appreciate if there is an epidemiological link between HHV-8 and cutaneous lymphomas.
