Changes in hypervariable region 1 of the envelope 2 glycoprotein of hepatitis C virus in children and adults with humoral immune defects

The N-terminal end of the hepatitis C virus (HCV) envelope glycoprotein E2 contains a stretch of 27 amino acids that exhibit increased variability. This hypervariable region 1 (HVR-1), as it is normally referred to, is thought to contain epitopes that come under humoral immune attack. In the present study, 10 patients (5 children and 5 adults) with humoral immune defects and chronic HCV infection were investigated, to see how HVR-1 sequences behave overtime in these patients who are unable to produce antibodies. Amplicons of this region showed little or no variation at all over time, indicating that quasi-species variation in this region is driven by the host's humoral immune response.