Clinical significance of hepatitis B surface antigen mutants
摘要
Hepatitis B virus(HBV) infection is major public health problem in many countries, with nearly 300 million people worldwide carrying HBV chronic infection and over 1 million deaths per year due to cirrhosis and liver cancer. Several hepatitis B surface antigen(HBs Ag) mutations have been described, most frequently due to single amino acid substitution and seldom to nucleotide deletion. The majority of mutations are located in the S region, but they have also been found in the pre-S1 and pre-S2 regions. Single amino acid substitutions in the major hydrophilic region of HBs Ag, called the a determinant, have been associated with immune escape and the consequent failure of HBV vaccination and HBs Ag detection, whereas deletions in the pre-S1 or pre-S2 regions have been associated with the development of hepatocellular carcinoma. This review article will focus on the HBs Ag mutants and their biological and clinical implications.