Serum interferon-inducible protein 10 levels predict hepatitis B s antigen seroclearance in patients with chronic hepatitis B

Background Hepatitis B s antigen (HBsAg) seroclearance is regarded as the optimal virological end-point. Aim To investigate the dynamic changes in serum cytokine levels around the time of HBsAg seroclearance. Methods This was a case-control study. Consecutive patients with chronic hepatitis B (CHB) who lost HBsAg were matched with those remained positive for HBsAg with same age, gender, HBeAg status and presence of cirrhosis in 1: 2 ratio. Relevant serum cytokines [interleukin (IL)-2, IL-3, IL-4, IL-7, IL-9, IL-10, IL-12, IL-15, IL-21 interferon-gamma, tumour necrosis factor-alpha (TNF-alpha), granulocyte macrophage colony-stimulating factor (GM-CSF) and interferon-inducible protein 10 (IP-10)] were assayed at the time (Year 0) and 3 years before (Year -3) HBsAg seroclearance. Results Seventy-one and 142 CHB patients who did and did not achieve HBsAg seroclearance were included. Mean age was 48 +/- 11 years; 76% were male, 20% had positive HBeAg, 99 (46%) patients received anti-viral therapy, and mean baseline HBV DNA was 3.78 +/- 2.28 log IU/mL vs. 4.36 +/- 2.13 log IU/mL respectively (P = 0.05). In those who achieved HBsAg seroclearance, serum IL-15 and GM-CSF levels decreased significantly from Year -3 to Year 0 (P = 0.017 and 0.05 respectively). When compared to controls, only serum IP-10 level was significantly lower at Year 0 than at Year -3 in patients with HBsAg seroclearance. Lower serum IP-10 level at Year 0 was the only factor associated with HBsAg seroclearance. There was no correlation between serum IP-10 and HBsAg levels around the time of HBsAg seroclearance. Conclusion Lower serum IP-10 level at Year 0 was the only factor associated with HBsAg seroclearance.