Genetic diversity and antigenic polymorphism in Plasmodium falciparum: extensive serological cross-reactivity between allelic variants of merozoite surface protein 2.
Diversity in the surface antigens of malaria parasites is generally assumed to be a mechanism for immune evasion, but there is little direct evidence that this leads to evasion of protective immunity. Here we show that alleles of the highly polymorphic merozoite surface protein 2 (MSP-2) can be grouped (within the known dimorphic families) into distinct serogroups; variants within a serogroup show extensive serological cross-reactivity. Cross-reactive epitopes are immunodominant, and responses to them may be boosted at the expense of responses to novel epitopes (original antigenic sin). The data imply that immune selection explains only some of the diversity in the msp-2 gene and that MSP-2 vaccines may need to include only a subset of the known variants in order to induce pan-reactive antibodies.
Franks
Simon
S
Institute of Cell, Animal and Population Biology, University of Edinburgh, United Kingdom.
Baton
Luke
L
Tetteh
Kevin
K
Tongren
Eric
E
Dewin
David
D
Akanmori
Bartholomew D
BD
Koram
Kojo A
KA
Ranford-Cartwright
Lisa
L
Riley
Eleanor M
EM
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D003001:Cloning, Molecular; D003429:Cross Reactions; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000235:genetics / Q000276:immunology*; D011110:Polymorphism, Genetic; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*
D000953:Antigens, Protozoan; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium