γγThe natural history of HBV infection in humans has three stages: 1. the high replication phase of immune tolerance, which is characterized by a stable high titer level of HBsAg in the blood, almost always detectable HBeAg and HBVDNA, and the presence of replicating HBV in the liver, but no MHC (major histocompatibility complex) on the hepatocyte membrane, also known as Human leukocyte antigen (HLA) molecule expression, and the genes controlling the body’s immune response ability mainly exist in the MHC, no MHC expression when the liver function is normal, so the immune system can not recognize HBV, and therefore can not clear the hepatitis B virus; this is also the reason why the DNA quantification is high and the liver function is normal.γγ2, low replication period during active response, when the HLA antigen is significantly expressed on the hepatocyte membrane, the immune system is activated to a certain extent, as shown by the increase in serum aminotransferase level, when the MHC molecule is activated to play a certain antiviral role; 3, low (non-)replication period after active response, when there is more integration of HBV and hepatocytes, HBV uses the host hepatocyte structure for replication, but does not HBV uses the host hepatocyte structure for replication, but does not impede hepatocyte metabolism, in a state of peaceful coexistence, and is not easily removed by the immune system. In summary, a prerequisite for hepatitis B conversion is the presence of immune system activation (i.e., abnormal liver function). It is also ineffective to have liver function abnormalities first and then do the conversion treatment after the enzyme lowering treatment is normal.