Naturally acquired antibodies to Plasmodium vivax Duffy binding protein (DBP) in Brazilian Amazon.
Duffy binding protein (DBP), a leading malaria vaccine candidate, plays a critical role in Plasmodium vivax erythrocyte invasion. Sixty-eight of 366 (18.6%) subjects had IgG anti-DBP antibodies by enzyme-linked immunosorbent assay (ELISA) in a community-based cross-sectional survey in the Brazilian Amazon Basin. Despite continuous exposure to low-level malaria transmission, the overall seroprevalence decreased to 9.0% when the population was reexamined 12 months later. Antibodies from 16 of 50 (36.0%) subjects who were ELISA-positive at the baseline were able to inhibit erythrocyte binding to at least one of two DBP variants tested. Most (13 of 16) of these subjects still had inhibitory antibodies when reevaluated 12 months later. Cumulative exposure to malaria was the strongest predictor of DBP seropositivity identified by multiple logistic regression models in this population. The poor antibody recognition of DBP elicited by natural exposure to P. vivax in Amazonian populations represents a challenge to be addressed by vaccine development strategies.
Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, Brazil. praflavia@cpqrr.fiocruz.br
Flávia A
FA
Souza-Silva
Mônica
M
da Silva-Nunes
Bruno A M
BA
Sanchez
Isabela P
IP
Ceravolo
Rosely S
RS
Malafronte
Cristiana F A
CF
Brito
Marcelo U
MU
Ferreira
Luzia H
LH
Carvalho
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology*; D001938:Brazil / Q000453:epidemiology; D019556:COS Cells; D002648:Child; D002675:Child, Preschool; D002522:Chlorocebus aethiops; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D016780:Malaria, Vivax / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology / Q000469:parasitology; D008297:Male; D008875:Middle Aged; D010966:Plasmodium vivax / Q000276:immunology* / Q000378:metabolism*; D015800:Protozoan Proteins / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000276:immunology*; D055815:Young Adult
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C066001:Duffy antigen binding protein, Plasmodium; D007074:Immunoglobulin G; D015800:Protozoan Proteins; D011956:Receptors, Cell Surface