(5) Natural Killer cell(NK cell) and Dendritic cell(DC cell) dysfunction: Multiple studies have confirmed that NK cell function is universally impaired in chronic hepatitis B patients, characterized by reduced cytotoxicity (including decreased expression of granzyme B and perforin), diminished secretion of antiviral cytokines (such as IFN-γ and TNF-α), and upregulated expression of inhibitory receptors (including NKG2A and Tim-3) (Li et al., 2017). This evidence concerns the gene TNF and chronic hepatitis B virus infection.