title: Tricomponent fusion complex comprising a viral antigen, a pentameric α-helical coiled-coil, and an immunoglobulin-binding domain as an effective antiviral vaccine.
abstract: The pentameric coiled-coil domain of cartilage oligomeric matrix protein (COMP) genetically fused to the Z domain of Staphylococcus aureus protein A, an immunoglobulin-binding domain (IBD), was evaluated as a viral antigen carrier complex. In a proof-of-concept study, recombinant Japanese encephalitis virus (JEV) E protein domain III (D3) was loaded onto the COMP-Z fusion protein by chemical conjugation, and the tricomponent complex generated, COMP-Z/D3, was evaluated for its vaccine efficacy in a mouse JEV infection model. Immunization with the complex conferred substantially greater protection against lethal JEV infection than the unloaded antigen. Next, a tricomponent complex was engineered in which the three molecular entities (the D3 antigen, COMP coiled-coil domain, and Z domain) were genetically connected in tandem to create the D3-COMP-Z tricomponent complex, or its reversal oriented construct, Z-COMP-D3. The fusion complexes were produced as inclusion bodies in Escherichia coli, but could be refolded to biologically active pentamers that retained the E protein antigenicity and the IBD function. Immunization with the refolded complexes conferred a high level of protection against lethal JEV infection, similar in efficacy to that of the tricomponent complex generated by chemical conjugation. These results demonstrate that the tricomponent complex, whether generated by chemical or genetic fusion, is a promising molecular design for the creation of effective subunit vaccines against viral infections.
authors.affiliation: Molecular Microbiology Group, Department of Tropical Infectious Diseases, COMB, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan; Division of Host Defense and Vaccinology, Department of Microbiology, Graduate School of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, Japan. Electronic address: tarakawa@comb.u-ryukyu.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Arakawa
authors.affiliation: Molecular Microbiology Group, Department of Tropical Infectious Diseases, COMB, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Harakuni
authors.affiliation: Molecular Microbiology Group, Department of Tropical Infectious Diseases, COMB, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Miyata
authors.affiliation: Jectas Innovators Co. Ltd., 1 Senbaru, Nishihara, Okinawa 903-0213, Japan.
authors.forename: Senji
authors.initials: S
authors.lastname: Tafuku
authors.affiliation: Department of Molecular Virology, Graduate School of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Tadano
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D001483:Base Sequence; D004672:Encephalitis, Japanese / Q000517:prevention & control; D005260:Female; D022321:Japanese Encephalitis Vaccines / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D054730:Protein Interaction Domains and Motifs; D013205:Staphylococcal Protein A / Q000276:immunology; D022223:Vaccines, Subunit / Q000276:immunology; D014759:Viral Envelope Proteins / Q000276:immunology*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D022321:Japanese Encephalitis Vaccines; D008562:Membrane Glycoproteins; D013205:Staphylococcal Protein A; D022223:Vaccines, Subunit; D014759:Viral Envelope Proteins; C080628:glycoprotein E, Japanese encephalitis virus
keywords: Cartilage oligomeric matrix protein; Delivery system; Japanese encephalitis virus E protein; Vaccine; α-Helical coiled-coil