Open AccessPlasmodium falciparum Malaria in the Peruvian Amazon, a Region of Low Transmission, Is Associated with Immunologic Memory
Author(s) -
Eva H. Clark,
Claudia J. Silva,
Greta E. Weiss,
Shanping Li,
Carlos Padilla,
Peter D. Crompton,
Jean N. Hernandez,
OraLee H. Branch
Publication year - 2012
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.05961-11
Subject(s) - biology , plasmodium falciparum , antigen , malaria , circumsporozoite protein , immunology , merozoite surface protein , malaria vaccine , virology , immunity , antibody , population , humoral immunity , immune system , medicine , environmental health
The development of clinical immunity toPlasmodium falciparum malaria is thought to require years of parasite exposure, a delay often attributed to difficulties in developing protective antibody levels. In this study, we evaluated severalP. falciparum vaccine candidate antigens, including apical membrane antigen 1 (AMA-1), circumsporozoite protein (CSP), erythrocyte binding antigen 175 (EBA-175), and the 19-kDa region of merozoite surface protein 1 (MSP119 ). After observing a more robust antibody response to MSP119 , we evaluated the magnitude and longevity of IgG responses specific to this antigen in Peruvian adults and children before, during, and afterP. falciparum infection. In this low-transmission region, even one reported prior infection was sufficient to produce a positive anti-MSP119 IgG response for >5 months in the absence of reinfection. We also observed an expansion of the total plasmablast (CD19+ CD27+ CD38high ) population in the majority of individuals shortly after infection and detected MSP1-specific memory B cells in a subset of individuals at various postinfection time points. This evidence supports our hypothesis that effective antimalaria humoral immunity can develop in low-transmission regions.