A plant signal peptide-hepatitis B surface antigen fusion protein with enhanced stability and immunogenicity expressed in plant cells

Punchapat Sojikul, Norene Buehner, Hugh Mason

Research output: Contribution to journalArticle

92 Scopus citations

Abstract

The use of transgenic plants to express orally immunogenic protein antigens is an emerging strategy for vaccine biomanufacturing and delivery. This concept has particular suitability for developing countries. One factor that has limited the development of this technology is the relatively modest levels of accumulation of some antigenic proteins in plant tissues. We used fusion protein design to improve expression of the hepatitis B surface antigen (HBsAg) by attempting to mimic the process of HBsAg targeting to the endoplasmic reticulum of human liver cells during hepatitis B virus infection. We created a gene encoding a recombinant HBsAg modified to contain a plant signal peptide fused to its amino terminus. The signal peptide from soybean vegetative storage protein vspA (VSPαS) directed endoplasmic reticulum targeting of HBsAg in plant cells, but was not cleaved and resulted in enhanced VSPαS-HBsAg fusion accumulation. This product was more stable and presented the protective "a" antigenic determinant to significantly higher levels than unmodified native HBsAg expressed in plant cells. It also showed a greater extent of intermolecular disulfide bond formation and formation of virus-like particles. Moreover, VSPαS-HBsAg stimulated higher levels of serum IgG than native HBsAg when injected into mice. We conclude that HBsAg tolerates a polypeptide fusion at the amino terminus and that VSPαS-HBsAg is an improved antigen for plant-based expression of a subunit vaccine for hepatitis B virus.

Original languageEnglish (US)
Pages (from-to)2209-2214
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume100
Issue number5
DOIs
StatePublished - Mar 4 2003

Keywords

  • Tobacco NT-1 cell
  • Transgenic plants
  • Vaccine

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'A plant signal peptide-hepatitis B surface antigen fusion protein with enhanced stability and immunogenicity expressed in plant cells'. Together they form a unique fingerprint.

  • Cite this