title: Distribution of Antibodies Specific to the 19-kDa and 33-kDa Fragments of Plasmodium vivax Merozoite Surface Protein 1 in Two Pathogenic Strains Infecting Korean Vivax Malaria Patients.
abstract: OBJECTIVE
  Plasmodium vivax merozoite surface protein 1 (PvMSP1) is the most intensively studied malaria vaccine candidate. Although high antibody response-inducing two C-terminal fragments of PvMSP1 (PvMSP1-19 and PvMSP1-42) are currently being developed as candidate malaria vaccine antigens, their high genetic diversity in various isolates is a major hurdle. The sequence polymorphism of PvMSP1 has been investigated; however, the humoral immune responses induced by different portions of this protein have not been evaluated in Korea.
  
  
  METHODS
  Two fragments of PvMSP1 were selected for this study: (1) PvMSP1-19, which is genetically conserved; and (2) PvMSP1-33, which corresponds to a variable portion. For the latter, two representative strains, Sal 1 and Belem, were included. Thus, three recombinant proteins, PvMSP1-19, PvMSP1-33 Sal 1, and PvMSP1-33 Belem, were produced in Escherichia coli and then tested by enzyme-linked immunosorbent assays using sera from 221 patients with vivax malaria.
  
  
  RESULTS
  Of the 221 samples, 198, 142, and 106 samples were seropositive for PvMSP1-19, PvMSP1-33 Sal 1, and PvMSP1-33 Belem, respectively. Although 100 samples were simultaneously seropositive for antibodies specific to all the recombinant proteins, 39 and six samples were respectively seropositive for antibodies specific to MSP1-33 Sal 1 and MSP1-33 Belem. Antibodies specific to PvMSP1-19 were the most prevalent.
  
  
  CONCLUSIONS
  Monitoring seroprevalence is essential for the selection of promising vaccine candidates as most of the antigenic proteins in P. vivax are highly polymorphic.
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Sylvatrie-Danne
authors.initials: SD
authors.lastname: Dinzouna-Boutamba
authors.affiliation: Division of Biosafety Evaluation and Control, Korea National Institute of Health, Cheongju, Korea.
authors.forename: Sanghyun
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea; College of Veterinary Medicine, Kyungpook National University, Daegu, Korea.
authors.forename: Ui-Han
authors.initials: UH
authors.lastname: Son
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Su-Min
authors.initials: SM
authors.lastname: Song
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Hye Soo
authors.initials: HS
authors.lastname: Yun
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: So-Young
authors.initials: SY
authors.lastname: Joo
authors.affiliation: College of Veterinary Medicine, Kyungpook National University, Daegu, Korea.
authors.forename: Dongmi
authors.initials: D
authors.lastname: Kwak
authors.affiliation: College of Veterinary Medicine, Kyungpook National University, Daegu, Korea.
authors.forename: Man Hee
authors.initials: MH
authors.lastname: Rhee
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Dong-Il
authors.initials: DI
authors.lastname: Chung
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Yeonchul
authors.initials: Y
authors.lastname: Hong
authors.affiliation: Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
authors.forename: Youn-Kyoung
authors.initials: YK
authors.lastname: Goo
keywords: Plasmodium vivax; merozoite surface protein 1; seroprevalence