Plasma interferon-gamma-inducible-protein 10 level as a predictive factor of spontaneous hepatitis B surface antigen seroclearance in chronic hepatitis B patients.

ABSTRACT

BACKGROUND AND AIM: Spontaneous seroclearance of hepatitis B surface antigen (HBsAg) is a rare event that occurs in patients that are chronically infected with the hepatitis B virus. As the functional cure and ultimate treatment endpoint of chronic hepatitis B (CHB), HBsAg seroclearance is an important milestone in the natural history of CHB and serves great clinical value. This study aims to identify host and viral factors associated with HBsAg seroclearance. METHODS: This is a retrospective study carried out in the Queen Mary Hospital, Hong Kong. By analyzing the plasma retrieved from the serum archive (collected during 2011-2021) of 100 CHB patients attending the hospital's liver clinic, the longitudinal cytokine profiles between the HBsAg-losers and the control groups were compared. RESULTS: Data revealed that plasma levels of IP-10 were significantly lower at 3-5 years prior to HBsAg seroclearance compared with patients who remained HBsAg positive (P < 0.05). Receiver operating characteristic curve analysis reveals that plasma IP-10 levels at multiple time points before HBsAg seroclearance return area under receivor-operating characteristic curve (AUC) greater than 0.7. Plasma IP-10 levels at 42.39 pg/mL produced an AUC = 0.723 with 74.0% sensitivity and 75.5% specificity to predict subsequent HBsAg seroclearance in the next 3-5 years. Low plasma IP-10 identified 91.4% patients with quantitative HBsAg < 100 IU/mL who would subsequently develop HBsAg seroclearance, compared with 37% with higher plasma IP-10 levels (P < 0.001). CONCLUSIONS: Low plasma levels of IP-10 are associated with subsequent HBsAg seroclearance, suggesting potential clinical utilities of measurement of IP-10 in predicting HBsAg seroclearance, especially among patients with low HBsAg.