title: Characterization of a novel merozoite surface protein of Plasmodium vivax, Pv41.
abstract: Since the genome of Plasmodium vivax was sequenced, few proteins have been characterized as highly immunogenic and candidates for inclusion in a vivax malaria vaccine. The P. vivax 41 (Pv41) protein has a signal peptide, one glutamate-rich domain in its central region, and two sexual stage s48/45 domains, and is characterized as a gametocyte surface protein; however, this protein may be expressed principally on the merozoite surface of parasites. The previous study reported the transcription, blood-stage expression, and subcellular localization of Pv41 within the parasite. In this study, the recombinant Pv41 protein was expressed as a soluble form, of a molecular mass ~44 kDa, by a cell-free expression system and was specifically recognized by animal immune sera and vivax patient sera. Evaluation of the human humoral immune response to Pv41 indicated a high immunogenicity, with 62.5% sensitivity and 95% specificity, by protein array. Immunofluorescence assays (IFA) using polyclonal anti-Pv41 antibodies showed that Pv41 was localized on the merozoite surface. The high immunogenicity of Pv41 indicates its potential as a vivax malaria vaccine candidate antigen, particularly in light of its location on the merozoite surface of the parasite.
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.forename: Feng
authors.initials: F
authors.lastname: Lu
authors.forename: Takafumi
authors.initials: T
authors.lastname: Tsuboi
authors.forename: Eun-Taek
authors.initials: ET
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D005260:Female; D006801:Humans; D017780:Malaria Vaccines / Q000276:immunology; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D052940:Merozoites / Q000737:chemistry / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D010966:Plasmodium vivax / Q000737:chemistry / Q000276:immunology*; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D017780:Malaria Vaccines; D008565:Membrane Proteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins