Non-allele specific antibody responses to genetically distinct variant forms of Plasmodium vivax Duffy binding protein (PvDBP-II) in Iranians exposed to seasonal malaria transmission.
Duffy binding protein (DBP) is a leading vaccine candidate of Plasmodium vivax. The binding domain of DBP (DBP-II) is polymorphic, that may be a major challenge for development of a broadly effective vaccine against vivax malaria. The present investigation was undertaken to explore whether the sequence diversity of DBP-II causes variation in naturally acquired anti-DBP-II antibodies. In this study, the five genetically distinct variants were expressed, and anti-DBP-II responses were measured in P. vivax-infected individuals (n=202). Finally, by performing immune-depletion ELISA experiments, antibody responses to the conserved sites of all allelic forms were evaluated using the corresponding and non-corresponding patients' sera (n=20). In this study, natural P. vivax infection produces IgG against all five examined variant forms of PvDBP-II with no statistically difference. Sequence analysis in the 20 selected samples (for antibody depletion experiment) showed eight distinct haplotypes, DBPI (n=1), DBPIII (n=3), DBPIV (n=1), DBPV (n=1), DBPVI (n=5), DBPIX (n=6), DBPX (n=1), and DBP XI (n=2). The results showed the presence of the cross-reactive antibody responses to heterologous variants of PvDBP-II in Iranian individuals who were infected with distinct allelic forms of the PvDBP-II. Therefore, it is proposed that the majority of antibodies recognized sharing B-cell epitopes and this could overcome the PvDBP-II variation as a one of the biggest challenges of PvDBP-II-based vaccine development.
Malaria and Vector Research Group (MVRG), Biotechnology Research Center, Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran.
Vahideh
V
Valizadeh
Malaria and Vector Research Group (MVRG), Biotechnology Research Center, Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran. Electronic address: zakeris@yahoo.com.
Sedigheh
S
Zakeri
Malaria and Vector Research Group (MVRG), Biotechnology Research Center, Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran.
Akram Abouei
AA
Mehrizi
Malaria and Vector Research Group (MVRG), Biotechnology Research Center, Pasteur Institute of Iran, Pasteur Avenue, P.O. Box 1316943551, Tehran, Iran.
Navid Dinparast
ND
Djadid
D051046:Amino-Acid N-Acetyltransferase; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology*; D000918:Antibody Specificity; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D018985:Epitopes, B-Lymphocyte; D005260:Female; D005786:Gene Expression Regulation; D014644:Genetic Variation; D006801:Humans; D007492:Iran / Q000453:epidemiology; D017780:Malaria Vaccines / Q000276:immunology; D016780:Malaria, Vivax / Q000453:epidemiology / Q000276:immunology* / Q000469:parasitology; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010966:Plasmodium vivax / Q000378:metabolism*; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000235:genetics / Q000276:immunology*; D012621:Seasons
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C066001:Duffy antigen binding protein, Plasmodium; D018985:Epitopes, B-Lymphocyte; D017780:Malaria Vaccines; D015800:Protozoan Proteins; D011956:Receptors, Cell Surface; D051046:Amino-Acid N-Acetyltransferase
Cross-reactive antibody; Duffy binding protein; Iran; Plasmodium vivax; Vaccine