Bioencapsulation of the hepatitis B surface antigen and its use as an effective oral immunogen

► Hepatitis antigens expressed in maize can provide a commercially feasible oral vaccine. ► Elevated levels of HBsAg were achieved in maize seed with embryo-preferred promoters. ► Optimization of genetic background and processing resulted in high HBsAg levels. ► Mice displayed robust systemic and mucosal immune responses after oral boosting. ► Immunogenicity of the material was not adjuvant-dependent.