Ferritin as a Nanoparticle Scaffold for Plant-Produced Next-Generation Subunit Vaccines

Area of Science:

• Biotechnology
• Vaccine Development
• Plant Molecular Farming

Background:

• Protein nanoparticles are promising for next-generation subunit vaccines due to enhanced immune interaction via particulate size and repetitive epitope display.
• Helicobacter pylori ferritin assembles into 24-subunit nanoparticles suitable for displaying foreign antigenic peptides.
• Previous ferritin-based vaccine research utilized bacterial, insect, and mammalian cell expression systems, but not plants.

Purpose of the Study:

• To investigate the feasibility of producing Helicobacter pylori ferritin in plants (Nicotiana benthamiana) for vaccine development.
• To assess the impact of genetic modification (preventing glycosylation, fusing a viral epitope) on ferritin accumulation and nanoparticle assembly in plants.

Main Methods:

• Recombinant expression of modified Helicobacter pylori ferritin in Nicotiana benthamiana, targeting the secretory pathway.
• Genetic fusion of a viral glyco-epitope to the N-terminus of the ferritin protein.
• Analysis of ferritin accumulation, glycosylation, nanoparticle assembly, and iron mineralization in plant-produced proteins.

Main Results:

• Accumulation of modified ferritin reached over 0.2 mg/g fresh weight in plant leaves.
• Genetic fusion with a viral glyco-epitope significantly increased ferritin accumulation and resulted in characteristic nanoparticle formation.
• The displayed epitope was efficiently glycosylated, and the fusion protein retained significant iron mineralization capacity.

Conclusions:

• Nicotiana benthamiana is a viable system for producing Helicobacter pylori ferritin nanoparticles for vaccine applications.
• Plant-based production offers a scalable platform for ferritin scaffold development.
• This study lays the foundation for utilizing plant-produced ferritin as a versatile scaffold in vaccine design.