| abstract |
A method for obtaining an immune response to hepatitis B surface antigen (HBsAG) by feeding the antigen in a plant material to an animal that is immunoreceptive to the HBsAg. It has now been discovered that the animal may be made immunoreceptive to HBsAg either by administering the plant material containing HBsAg in conjunction with a suitable adjuvant or by prior primary immunization. When the animal is made immunoreceptive by a prior , e.g. primary, immunization, an immune response to HBsAg may be boosted in the animal by feeding the animal the plant material containing the HBsAg. For example, an animal, e.g. a human, that previously had a positive response to primary immunization against hepatitis B, can have a booster response to HBsAg by feeding the animal the antigen in a plant material. The plant material is a substance comprising a physiologically acceptable plant material, especially potatoes, containing hepatitis B surface antigen (HBsAg). The HBsAg in the plant results from expression by the plant of HBsAg due to genetic alteration. |