title: Biophysical characterization and conformational stability of Ebola and Marburg virus-like particles.
abstract: The filoviruses, Ebola virus and Marburg virus, cause severe hemorrhagic fever with up to 90% human mortality. Virus-like particles of EBOV (eVLPs) and MARV (mVLPs) are attractive vaccine candidates. For the development of stable vaccines, the conformational stability of these two enveloped VLPs produced in insect cells was characterized by various spectroscopic techniques over a wide pH and temperature range. Temperature-induced aggregation of the VLPs at various pH values was monitored by light scattering. Temperature/pH empirical phase diagrams (EPDs) of the two VLPs were constructed to summarize the large volume of data generated. The EPDs show that both VLPs lose their conformational integrity above about 50°C-60°C, depending on solution pH. The VLPs were maximally thermal stable in solution at pH 7-8, with a significant reduction in stability at pH 5 and 6. They were much less stable in solution at pH 3-4 due to increased susceptibility of the VLPs to aggregation. The characterization data and conformational stability profiles from these studies provide a basis for selection of optimized solution conditions for further vaccine formulation and long-term stability studies of eVLPs and mVLPs.
authors.affiliation: Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas 66047, USA.
authors.forename: Lei
authors.initials: L
authors.lastname: Hu
authors.forename: Jared M
authors.initials: JM
authors.lastname: Trefethen
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Zeng
authors.forename: Luisa
authors.initials: L
authors.lastname: Yee
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ohtake
authors.forename: David
authors.initials: D
authors.lastname: Lechuga-Ballesteros
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Warfield
authors.forename: M Javad
authors.initials: MJ
authors.lastname: Aman
authors.forename: Sergey
authors.initials: S
authors.lastname: Shulenin
authors.forename: Robert
authors.initials: R
authors.lastname: Unfer
authors.forename: Sven G
authors.initials: SG
authors.lastname: Enterlein
authors.forename: Vu
authors.initials: V
authors.lastname: Truong-Le
authors.forename: David B
authors.initials: DB
authors.lastname: Volkin
authors.forename: Sangeeta B
authors.initials: SB
authors.lastname: Joshi
authors.forename: C Russell
authors.initials: CR
authors.lastname: Middaugh
mesh_terms: D000818:Animals; D000914:Antibodies, Viral; D016367:Baculoviridae / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D046129:Ebola Vaccines / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D029043:Ebolavirus / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005822:Genetic Vectors; D019142:Hemorrhagic Fever, Ebola / Q000276:immunology / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007313:Insecta; D008379:Marburg Virus Disease / Q000276:immunology / Q000378:metabolism*; D029024:Marburgvirus / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008968:Molecular Conformation; D013696:Temperature; D058425:Vaccines, Virus-Like Particle / Q000032:analysis / Q000737:chemistry / Q000276:immunology / Q000378:metabolism; D014771:Virion / Q000737:chemistry*
chemical_list: D000914:Antibodies, Viral; D046129:Ebola Vaccines; D058425:Vaccines, Virus-Like Particle