title: Perspective of Peptide Vaccine Composed of Epitope Peptide, CpG-DNA, and Liposome Complex Without Carriers.
abstract: The magnitude and specificity of cell-mediated and humoral immunity are critically determined by peptide sequences; peptides corresponding to the B- or T-cell receptor epitopes are sufficient to induce an effective immune response if delivered properly. Therefore, studies on the screening and application of peptide-based epitopes have been done extensively for the development of therapeutic antibodies and prophylactic vaccines. However, the efficacy of immune response and antibody production by peptide-based immunization is too limited for human application at the present. To improve the efficacy of vaccines, researchers formulated adjuvants such as alum, water-in-oil emulsion, and Toll-like receptor agonists. They also employed liposomes as delivering vehicles to stimulate immune responses. Here, we review our recent studies providing a potent method of epitope screening and antibody production without conventional carriers. We adopted Lipoplex(O), comprising a natural phosphodiester bond CpG-DNA and a specific liposome complex, as an adjuvant. Lipoplex(O) induces potent stimulatory activity in humans as well as in mice, and immunization of mice with several peptides along with Lipoplex(O) without general carriers induces significant production of each peptide-specific IgG2a. Immunization of peptide vaccines against virus-associated antigens in mice has protective effects against the viral infection. A peptide vaccine against carcinoma-associated antigen and the peptide-specific monoclonal antibody has functional effects against cancer cells in mouse models. In conclusion, we improved the efficacy of peptide vaccines in mice. Our strategy can be applied in development of therapeutic antibodies or in defense against pandemic infectious diseases through rapid screening of potent B-cell epitopes.
authors.affiliation: Department of Biochemistry, College of Natural Sciences, Chungbuk National University, Cheongju, South Korea.
authors.forename: Younghee
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Division of Molecular and Life Sciences, College of Science and Technology, Hanyang University, Ansan, South Korea.
authors.forename: Young Seek
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Laboratory of Developmental Biology and Genomics, College of Veterinary Medicine, Research Institute for Veterinary Science BK21, Program for Veterinary Science, Seoul National University, Seoul, South Korea.
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Cho
authors.affiliation: Department of Microbiology, College of Medicine, Hallym University, Chuncheon, South Korea; Center for Medical Science Research, College of Medicine, Hallym University, Chuncheon, South Korea. Electronic address: hjookwon@hallym.ac.kr.
authors.forename: Hyung-Joo
authors.initials: HJ
authors.lastname: Kwon
mesh_terms: D004269:DNA, Bacterial / Q000737:chemistry / Q000276:immunology*; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D008081:Liposomes / Q000737:chemistry / Q000276:immunology; D009838:Oligodeoxyribonucleotides / Q000737:chemistry / Q000276:immunology*; D010455:Peptides / Q000737:chemistry / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000737:chemistry / Q000276:immunology*
chemical_list: C408982:CPG-oligonucleotide; D004269:DNA, Bacterial; D000939:Epitopes; D008081:Liposomes; D009838:Oligodeoxyribonucleotides; D010455:Peptides; D014614:Vaccines, Synthetic
keywords: Adjuvant; CpG-DNA; Epitope screening; Liposome; Peptide; Therapeutics; Vaccine