TLR9 and chronic hepatitis B virus infection: Previously, when exploring the role of TLR1-10 in chronic hepatitis B, it was found that the expressions of only TLR9 and TLR10 were related to HBV load, suggesting that these 2 recognition receptors are closely related to HBV replication.[22,23] The extracellular region of TLR9 is crucial for identifying foreign microorganisms.[24] It has the ability to recognize HBV virus and initiate immune response by identifying nonmethylated CpG gene sequences.