Plant-based vaccines against human hepatitis B virus.

Human hepatitis B virus (HBV) causes a communicable disease that spreads worldwide and has brought about considerable economic losses due to human mortality and morbidity. HBV fails to reproduce in both cell cultures and laboratory animals; however, it is known that excess virion surface protein named hepatitis B surface antigen (HBsAg) is produced during viral replication and circulates in the blood of carriers as noninfectious particles of 22-nm diameter. It had been shown that purified HBsAg particles induce an efficient systemic immune response after injection. Consequently, subunit HBV vaccines based on HBsAg synthesized in yeasts or mammalian cell culture are currently used. Taking into account that hepatitis B is a sexually transmitted disease, development of a mucosal HBV vaccine would be beneficial. In this article, we analyze the data on development of plant-based HBV vaccines.