Association between Affinity of Anti-HCV Antibodies and Viral Load in Patients with HCV Infection: a New Method to Estimate Patients' Immune Status

Abstract

The status of immune response to HCV infection cannot be accurately predicted by the HCV antibody test alone. Our paper aims to explore differences in total activity, quantity, and affinity of anti-HCV antibodies in patients with HCV infection, proposing a novel measurement of antibody affinity and providing a promising understanding into immune response to HCV. Serum samples from 106 patients with HCV infection were collected. Anti-HCV antibodies, HCV RNA, ALT, and AST were measured. The samples were divided into three groups based on ALT, AST level (both normal, one abnormal, and both abnomal) and HCV-RNA level (negative, low viral load, and high viral load). Differences in total activity, quantity, and affinity of anti-HCV antibodies were analyzed. The quantity of anti-HCV antibodies in the normal ALT and AST groups were significantly lower than that of the other two groups (p < 0.05). In contrast, the antibody affinity of the normal ALT and AST groups was significantly higher than that detected in the other two groups (p < 0.05). The total activity and quantity of anti-bodies in the low and high viral load groups were significantly higher than those measured in the HCV RNA-negative group (p < 0.05). The HCV RNA-negative group had a significantly higher antibody affinity than the other two groups (p < 0.05). HCV-RNA level was negatively correlated with affinity (p < 0.05). Our results indicate that the total activity, quantity, and affinity of anti-HCV antibodies may reflect viral load in patients infected with HCV and could serve as valuable information for clinical applications.