Conformational analysis of hepatitis B surface antigen fusions in an Agrobacterium-mediated transient expression system

Zhong Huang, Hugh Mason

Research output: Contribution to journalArticlepeer-review

58 Scopus citations


Vaccine antigens have been successfully produced in transgenic plants for oral immunization. Recently, a fusion strategy has been adopted to produce multicomponent vaccines and to target antigens to mucosal sites for enhanced oral immunogenicity. However, antigen fusions may not be folded correctly due to steric hindrance and may thus lose their potency. Here, we describe an Agrobacterium-mediated transient assay that provides enough antigen-expressing material at 2 days post-transfection to evaluate antigen conformation. Using the hepatitis B surface antigen (HBsAg) as a model antigen and the green fluorescent protein (GFP) as a model fusion partner, we showed that transiently expressed HBsAg and an HBsAg fusion with GFP at the N-terminus (GFP:HBsAg), but not the HBsAg fusion with GFP at the C-terminus (HBsAg:GFP), formed the 'a' determinant and virus-like particles (VLPs), similar to yeast-derived vaccine HBsAg. Thus, it is feasible to modify the HBsAg with an N-terminal fusion of up to 239 amino acids without altering its major antigenic properties. Our results also demonstrate that the Agrobacterium-mediated transient expression system can be used to evaluate the conformation of plant-based vaccines or other pharmaceutical proteins in a high-throughput manner.

Original languageEnglish (US)
Pages (from-to)241-249
Number of pages9
JournalPlant Biotechnology Journal
Issue number3
StatePublished - May 2004


  • Fusion
  • Green fluorescent protein
  • Hepatitis B surface antigen
  • Transient expression
  • Vaccine
  • Virus-like particle

ASJC Scopus subject areas

  • Biotechnology
  • Agronomy and Crop Science
  • Plant Science


Dive into the research topics of 'Conformational analysis of hepatitis B surface antigen fusions in an Agrobacterium-mediated transient expression system'. Together they form a unique fingerprint.

Cite this