Genetic heterogeneity of the hypervariable region I of Hepatitis C virus and lymphoproliferative disorders

Abstract

B-cell lymphoproliferative disorders (BCLD) have been associated with chronic hepatitis C virus (HCV) infection. The HCV glycoprotein E2 (gpE2) hypervariable region I (HVR-I) may be a potential antigenic candidate to promote B-cell proliferation. The purpose of this study was to analyze the influence of HVR-I sequence variability in the development of BCLD. HVR-I sequences were studied in 29 chronically HCV-infected patients with (n=15) or without (n=14) BCLD. After PCR amplification of the gpE2 region, analysis of the 81 bp HVR-I encoding fragment was performed on 7-18 clones per patient. HVR-I sequence complexity was slightly lower in patients with BCLD (mean 0.347) than without (0.468) (P=0.2), though, sequence diversities were similar (0.0370 vs 0.0954, P=0.239). Phylogenetic analysis did not reveal any BCLD-associated clustering. In our population, neither the recently described insertion between positions 1 and 2 of HVR-I nor residues at positions 4 and 13 were particularly linked to BCLD. As previously described, we confirm the high degree of conservation of HVR-I residues T-2, G-6 and G-23 in our patients. Contrary to recent findings, our analysis based on multiple clones per patient analysis did not reveal any particular motif associated with BCLD.