title: Antigenicity studies in humans and immunogenicity studies in mice: an MSP1P subdomain as a candidate for malaria vaccine development.
abstract: The newly identified GPI-anchored Plasmodium vivax merozoite surface protein 1 paralog (MSP1P) has a highly antigenic C-terminus that binds erythrocytes. To characterize the antigenicity and immunogenicity of two regions (PvMSP1P-19 and -33) of the highly conserved C-terminus of MSP1P relative to PvMSP1-19, 30 P. vivax malaria-infected patients and two groups of mice (immunized with PvMSP1P-19 or -33) were tested for IgG subclass antibodies against PvMSP1P-19 and -33 antigens. In the patients infected with P. vivax, IgG1 and IgG3 levels were significantly higher than those levels in healthy individuals, and were the predominant response to the two C-terminal fragments of PvMSP1P (p < 0.05). In mice immunized with PvMSP1P-19, IgG1 levels were the highest while IgG2b levels were similar to IgG1 levels. The levels of Th1 cytokines in mice immunized with PvMSP1P-19 or -33 were significantly higher than those in mice immunized with PvMSP1-19 (p < 0.05). Our results indicate that: (i) IgG1 and IgG3 (IgG2b in mice) are predominant IgG subclasses in both patients infected with P. vivax and mice immunized with PvMSP1P-19 or -33; (ii) the C-terminus of MSP1P induces a Th1-cytokine response. This immune profiling study provides evidence that MSP1P may be a potential candidate for vivax vaccine.
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 200-701, Republic of Korea.
authors.forename: Yang
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Department of Parasitology and Tropical Medicine, Seoul National University College of Medicine, and Institute of Endemic Disease, Seoul National University Medical Research Center, Seoul 110-799, Republic of Korea; Seoul National University Bundang Hospital, Seongnam 463-707, Republic of Korea.
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Shin
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 200-701, Republic of Korea.
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 200-701, Republic of Korea.
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Microbiology and Immunology, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 200-701, Republic of Korea.
authors.forename: Jongseon
authors.initials: J
authors.lastname: Choe
authors.affiliation: Division of Malaria Research, Proteo-Science Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Tsuboi
authors.affiliation: Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 200-701, Republic of Korea. Electronic address: ethan@kangwon.ac.kr.
authors.forename: Eun-Taek
authors.initials: ET
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D002648:Child; D016207:Cytokines / Q000378:metabolism; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D017780:Malaria Vaccines / Q000276:immunology* / Q000302:isolation & purification*; D016780:Malaria, Vivax / Q000517:prevention & control*; D008297:Male; D020066:Merozoite Surface Protein 1 / Q000276:immunology*; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D010966:Plasmodium vivax / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan; D016207:Cytokines; D007074:Immunoglobulin G; D017780:Malaria Vaccines; D020066:Merozoite Surface Protein 1
keywords: Cytokines; IgG subclasses; Immunogenicity; MSP1P; Plasmodium vivax