Natural killer cells function in acute and chronic hepatitis B patients

Abstract

Objective To investigate the differences in frequency and function of natural killer cells (NK) between chronic hepatitis B (CHB) and acute hepatitis B (AHB). Methods Patients with AHB and those with CHB in immune active (IA) phase were enrolled. The frequencies of NK, CD56dimNK, CD56brightNK and the expression of functional molecules IFNAR2 and NKp46 on the surface of NK cells were detected respectively among patients with CHB in IA phase, patients with AHB, and those recovered from AHB. At the same time, their correlations with ALT, HBV DNA and HBV markers were analyzed. Results Between IA and AHB, the frequencies of NK cells and NKp46dim NK cells in AHB cases were significantly lower than those in IA cases, but the frequency of NKp46high NK cells in AHB was higher than that in IA. For patients who recovered from AHB, the frequency of NK cells and NKp46dim NK cells increased; the varied ranges of frequencies of CD56dimNK, IFNAR2+ NK and NKp46+ NK cells were on the rise, while the frequency of NKp46high NK cells decreased after the recovery from AHB, and the varied ranges of CD56brightNK and IFNAR2MFI, NKp46MFI decreased. In AHB, HBVDNA loads were positively correlated with ALT levels. Before and after the recovery of AHB: ΔHBV DNA and ΔALT, Δ NK/LY (%) were positively correlated; ΔALT and ΔNKp46highNK/NK(%), ΔNKp46MFI, ΔIFNAR2MFI were positively correlated. Conclusions In CHB immune active phase, the activity of peripheral blood NK cells was too weak to remove the virus, but NK cells play an important role in eliminating the viruses and mediating liver tissue inflammation in AHB. Key words: Natural killer cells; Chronic hepatitis B; Acute hepatitis B; Hepatitis B virus