Comparison of IgG reactivities to Plasmodium vivax merozoite invasion antigens in a Brazilian Amazon population.
Naturally acquired antibody reactivity to two major Plasmodium vivax vaccine candidates was investigated in 294 donors from three malaria-endemic communities of Rondônia state, Brazil. Antibody recognition of recombinantly expressed antigens covering five different regions of P. vivax reticulocyte binding protein 1 (PvRBP1) and region II of P. vivax Duffy binding protein (PvDBP-RII) were compared. Positive IgG responses to these antigens were significantly related to the level of malaria exposure in terms of past infections and years of residence in the endemic area when corrected for age. The highest prevalence of anti-PvRBP1 total IgG antibodies corresponded to the amino acid regions denoted PvRBP1(431-748) (41%) and PvRBP1(733-1407) (47%). Approximately one-fifth of positively responding sera had titers of at least 1:1,600. Total IgG responses to PvDBP-RII were more prevalent (67%), of greater magnitude, and acquired more rapidly than those to individual PvRBP1 antigens. Responses to both PvRBP1 and PvDBP-RII were biased toward the cytophilic subclasses IgG1 and IgG3. These data provide the first insights on acquired antibody responses to PvRBP1 and a comparative view with PvDBP-RII that may prove valuable for understanding protective immune responses to these two vaccine candidates as they are evaluated as components of multitarget blood-stage vaccines.
Tran
Tuan M
TM
Emory Vaccine Center & Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329, USA.
Oliveira-Ferreira
Joseli
J
Moreno
Alberto
A
Santos
Fatima
F
Yazdani
Syed S
SS
Chitnis
Chetan E
CE
Altman
John D
JD
Meyer
Esmeralda V-S
EV
Barnwell
John W
JW
Galinski
Mary R
MR
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D001938:Brazil / Q000453:epidemiology; D002648:Child; D004375:Duffy Blood-Group System / Q000378:metabolism; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000145:classification; D017780:Malaria Vaccines; D016780:Malaria, Vivax / Q000453:epidemiology* / Q000276:immunology; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology*; D008875:Middle Aged; D010966:Plasmodium vivax / Q000254:growth & development / Q000276:immunology*; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D004375:Duffy Blood-Group System; D007074:Immunoglobulin G; D017780:Malaria Vaccines; D008565:Membrane Proteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins; C075483:reticulocyte-binding protein, Plasmodium vivax