title: Bioencapsulation of the hepatitis B surface antigen and its use as an effective oral immunogen.
abstract: Hepatitis B remains a major global health problem despite the availability of a safe and effective vaccine. Segments of the population lack access to or respond poorly to the parenteral vaccine, perpetuating the infection-transmission cycle. A low cost, orally delivered vaccine has the potential to alleviate many of these problems. Here we describe the expression of a bioencapsulated hepatitis B surface antigen (HBsAg) in maize and its immunogenicity, demonstrating for the first time a commercially feasible oral subunit vaccine production system for a major disease. This work surmounts previous barriers to plant-produced vaccines by expressing HBsAg at much higher levels and retaining antigen immunogenicity post-processing: factors which facilitated a robust immune response in mice without the need for an adjuvant. This method provides a practical solution to the delivery of a low-cost, stable oral vaccine.
authors.affiliation: Applied Biotechnology Institute, Cal Poly Tech Park, San Luis Obispo, CA 93407, United States.
authors.forename: Celine A
authors.initials: CA
authors.lastname: Hayden
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Streatfield
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Lamphear
authors.forename: Gina M
authors.initials: GM
authors.lastname: Fake
authors.forename: Todd K
authors.initials: TK
authors.lastname: Keener
authors.forename: John H
authors.initials: JH
authors.lastname: Walker
authors.forename: John D
authors.initials: JD
authors.lastname: Clements
authors.forename: Debra D
authors.initials: DD
authors.lastname: Turner
authors.forename: Ian R
authors.initials: IR
authors.lastname: Tizard
authors.forename: John A
authors.initials: JA
authors.lastname: Howard
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D016503:Drug Delivery Systems; D006514:Hepatitis B Surface Antigens / Q000008:administration & dosage* / Q000276:immunology*; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D022462:Vaccines, Edible / Q000008:administration & dosage / Q000276:immunology; D003313:Zea mays / Q000235:genetics / Q000378:metabolism
chemical_list: D000914:Antibodies, Viral; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D022462:Vaccines, Edible