Osong Public Health Res Perspect.  2016 Aug;7(4):213-219. 10.1016/j.phrp.2016.05.006.

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

• Dinzouna-Boutamba SD
• Lee S
• Son UH
• Song SM
• Yun HS
• Joo SY
• Kwak D
• Rhee MH
• Chung DI
• Hong Y
• Goo YK

• KMID: 2518272
• DOI: http://doi.org/10.1016/j.phrp.2016.05.006

Abstract

Objectives
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.
Conclusion
Monitoring seroprevalence is essential for the selection of promising vaccine candidates as most of the antigenic proteins in P. vivax are highly polymorphic.

Keyword

merozoite surface protein 1; seroprevalence