title: Plasmodium falciparum: sequence diversity and antibody recognition of the Merozoite surface protein-2 (MSP-2) in Brazilian Amazonia.
abstract: The merozoite surface protein-2 (MSP-2) of Plasmodium falciparum comprises repeats flanked by dimorphic domains defining the allelic families FC27 and IC1. Here, we examined sequence diversity at the msp-2 locus in Brazil and its impact on MSP-2 antibody recognition by local patients. Only 25 unique partial sequences of msp-2 were found in 61 isolates examined. The finding of identical msp-2 sequences in unrelated parasites, collected 6-13 years apart, suggests that no major directional selection is exerted by variant-specific immunity in this malaria-endemic area. To examine antibody cross-reactivity, recombinant polypeptides derived from locally prevalent and foreign MSP-2 variants were used in ELISA. Foreign IC1-type variants, such as 3D7 (currently tested for human vaccination), were less frequently recognized than FC27-type and local IC1-type variants. Antibodies discriminated between local and foreign IC1-type variants, but cross-recognized structurally different local IC1-type variants. The use of evolutionary models of MSP-2 is suggested to design vaccines that minimize differences between local parasites and vaccine antigens.
authors.affiliation: Departamento de Parasitologia, Instituto de Ciências Biomédicas da Universidade de São Paulo, Av. Prof. Lineu Prestes 1374, Cidade Universitária, 05508-900 São Paulo, Brazil.
authors.forename: Angela Pedroso
authors.initials: AP
authors.lastname: Tonon
authors.forename: Erika Hellena Esther
authors.initials: EH
authors.lastname: Hoffmann
authors.forename: Lucimeire Antonelli da
authors.initials: LA
authors.lastname: Silveira
authors.forename: Adálton Guimarães
authors.initials: AG
authors.lastname: Ribeiro
authors.forename: Clara Rosa da Silva
authors.initials: CR
authors.lastname: Gonçalves
authors.forename: Paulo Eduardo Martins
authors.initials: PE
authors.lastname: Ribolla
authors.forename: Gerhard
authors.initials: G
authors.lastname: Wunderlich
authors.forename: Marcelo Urbano
authors.initials: MU
authors.lastname: Ferreira
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood / Q000276:immunology*; D000953:Antigens, Protozoan / Q000737:chemistry / Q000276:immunology*; D001483:Base Sequence; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D014644:Genetic Variation; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007223:Infant; D016778:Malaria, Falciparum / Q000453:epidemiology / Q000469:parasitology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000235:genetics / Q000276:immunology*; D015800:Protozoan Proteins / Q000737:chemistry / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium