title: Characterization of the disassembly and reassembly of the HBV glycoprotein surface antigen, a pliable nanoparticle vaccine platform.
abstract: While nanoparticle vaccine technology is gaining interest due to the success of vaccines like those for the human papillomavirus that is based on viral capsid nanoparticles, little information is available on the disassembly and reassembly of viral surface glycoprotein-based nanoparticles. One such particle is the hepatitis B virus surface antigen (sAg) that exists as nanoparticles. Here we show, using biochemical analysis coupled with electron microscopy, that sAg nanoparticle disassembly requires both reducing agent to disrupt intermolecular disulfide bonds, and detergent to disrupt hydrophobic interactions that stabilize the nanoparticle. Particles were otherwise resistant to salt and urea, suggesting the driving mechanism of particle formation involves hydrophobic interactions. We reassembled isolated sAg protein into nanoparticles by detergent removal and reassembly resulted in a wider distribution of particle diameters. Knowledge of these driving forces of nanoparticle assembly and stability should facilitate construction of epitope-displaying nanoparticles that can be used as immunogens in vaccines.
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 50 South Drive, Room 6351, Bethesda, MD 20892, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Gallagher
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 50 South Drive, Room 6351, Bethesda, MD 20892, USA.
authors.forename: Udana
authors.initials: U
authors.lastname: Torian
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 50 South Drive, Room 6351, Bethesda, MD 20892, USA.
authors.forename: Dustin M
authors.initials: DM
authors.lastname: McCraw
authors.affiliation: Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 50 South Drive, Room 6351, Bethesda, MD 20892, USA. Electronic address: harrisau@mail.nih.gov.
authors.forename: Audray K
authors.initials: AK
authors.lastname: Harris
mesh_terms: D006509:Hepatitis B / Q000517:prevention & control / Q000821:virology*; D006514:Hepatitis B Surface Antigens / Q000737:chemistry* / Q000378:metabolism; D017325:Hepatitis B Vaccines / Q000737:chemistry* / Q000378:metabolism; D006515:Hepatitis B virus / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D014771:Virion / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines
keywords: Assembly; Disassembly; Electron microscopy; Glycoprotein nanoparticles; HBV surface antigen; Reassembly; Tomography; Vaccines; Virus structure