Plasmodium falciparum: sequence diversity and antibody recognition of the Merozoite surface protein-2 (MSP-2) in Brazilian Amazonia

• Published in: Experimental parasitology Vol. 108; no. 3; pp. 114 - 125
• Main Authors: Tonon, Angela Pedroso, Hoffmann, Erika Hellena Esther, Silveira, Lucimeire Antonelli da, Ribeiro, Adálton Guimarães, Gonçalves, Clara Rosa da Silva, Ribolla, Paulo Eduardo Martins, Wunderlich, Gerhard, Ferreira, Marcelo Urbano
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-11-2004
• Subjects: Adolescent; Adult; Aged; Alleles; Amino Acid Sequence; Animals; Antibodies, Protozoan - blood; Antibodies, Protozoan - immunology; Antigenic diversity; Antigens, Protozoan - chemistry; Antigens, Protozoan - immunology; Base Sequence; Brazil - epidemiology; Child; Child, Preschool; Cross Reactions; degrees of freedom; ELISA; Enzyme-Linked Immunosorbent Assay; Female; Genetic Variation; glutathione- S-transferase; GST; Humans; Immunoglobulin G - immunology; Immunoglobulin M - immunology; Infant; Malaria parasites; Malaria, Falciparum - epidemiology; Malaria, Falciparum - parasitology; Male; merozoite surface protein-1; merozoite surface protein-2; Middle Aged; Molecular Sequence Data; MSP-1; MSP-2; PCR; Plasmodium falciparum; Plasmodium falciparum - genetics; Plasmodium falciparum - immunology; polymerase chain reaction; Protozoa; Protozoan Proteins - chemistry; Protozoan Proteins - immunology; SDS–PAGE; single nucleotide polymorphism; SNP; sodium dodecyl sulfate–polyacrylamide gel electrophoresis; standard deviation; Vaccine; Brazil; Brazil, Amazonia; Protozoa; df; GST; Vaccine; MSP-2; SDS–PAGE; MSP-1; SD; SNP; Malaria parasites; Antigenic diversity; PCR; ELISA
• ISSN: 0014-4894; 1090-2449
• DOI: 10.1016/j.exppara.2004.08.001

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.