| abstract |
Plant expression vectors comprising at least two expression cassettes are provided which function to reduce transcriptional silencing of polynucleotide expression. Further, novel plant expression vectors for expression of immunogenic polypeptides, including HBsAg, are provided. The plant expression vectors can be used to produce immunogenic polypeptides, including HBsAg, in edible plant tissues. The edible plant tissues can be used to elicit an immune response in humans and animals when the plant tissues are consumed. |